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doc: Intuition bootcamp — comprehensive enrichment of all subsystem articles
Transformed 8 stub articles (720 lines total) into full bootcamp-grade references (5,100+ lines) with architecture diagrams, complete code examples, struct field references, pitfalls, and best practices. IDCMP (idcmp.md — 1,060 lines): - IntuiMessage field reference with types, sizes, value ranges - Use-case cookbook: double-click, rubber-band, multi-signal, BOOPSI - When to use IDCMP vs alternatives (decision flowchart) - 5 named antipatterns with WRONG/RIGHT code - Memory safety checklist and defensive event loop template - Cross-platform comparison table (Win32, X11, Cocoa, Qt) Input Events (input_events.md — 850 lines): - Event class routing and QoS analysis (priority-as-QoS hierarchy) - Intuition consumption table (what survives the handler chain) - lowlevel.library bypass for CD32/game input - Latency analysis with pipeline timing budget (68000 vs 68040) - Input strategy comparison (IDCMP vs handler vs direct hardware) - Game input patterns: direct HW polling, CIA keyboard, hybrid handler - Signal pattern for proper handler→application communication Windows (windows.md — 370 lines): - Window anatomy diagram, WA_ tag reference tables - Refresh modes comparison (Simple/Smart/SuperBitMap) - Window types: standard, backdrop, borderless, GimmeZeroZero - Coordinate system, border offsets, struct Window fields - Modification API (move, resize, title, busy pointer) Gadgets (gadgets.md — 403 lines): - Three-generation evolution (raw/GadTools/BOOPSI) - Complete GadTools lifecycle with setup, creation, events, cleanup - Runtime state updates (GadTools vs raw Intuition) - Raw struct Gadget: GFLG_*, GACT_*, GTYP_* flag tables - Proportional and string gadget internals BOOPSI (boopsi.md — 505 lines): - Class hierarchy Mermaid diagram - Method dispatch sequence diagram - ICA interconnection architecture (icclass, modelclass, ICTARGET_IDCMP) - Full custom gadget class tutorial (4 steps with complete code) - Built-in class reference table - C++/Qt analog comparison table Menus (menus.md — 378 lines): - Menu hierarchy diagram (Menu → Item → Sub-Item) - GadTools NewMenu workflow with field reference - Event handling with multi-select chain walking - Checkmark/mutual exclusion, sub-menus, dynamic modification - Keyboard shortcut system (single-char and NM_COMMANDSTRING) Requesters (requesters.md — 370 lines): - EasyRequest return value logic table - ASL file requester with multi-select and full tag reference - ASL font and screenmode requesters - Non-blocking BuildEasyRequest/SysReqHandler pattern - Requester state persistence IntuitionBase (intuition_base.md — 267 lines): - Library version table (OS 1.2 through 3.2.x) - Struct field reference with safety annotations - ViewLord architecture diagram - LockIBase vs Forbid/Permit guidance - Complete library function overview (5 categories) README index updated with enriched article descriptions.
This commit is contained in:
Ilia Sharin
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@ -8,15 +8,15 @@ Intuition is the AmigaOS windowing system and user interface manager. It sits be
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| File | Description |
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|---|---|
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| [intuition_base.md](intuition_base.md) | IntuitionBase structure and global state |
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| [screens.md](screens.md) | Screen, OpenScreen, CloseScreen, SA_ tags |
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| [windows.md](windows.md) | Window, OpenWindow, IDCMP messaging |
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| [gadgets.md](gadgets.md) | Gadget structures, GadTools, BOOPSI |
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| [menus.md](menus.md) | Menu, MenuItem, MenuStrip construction |
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| [requesters.md](requesters.md) | EasyRequest, AutoRequest, file requesters |
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| [idcmp.md](idcmp.md) | IDCMP message classes and IntuiMessage |
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| [boopsi.md](boopsi.md) | BOOPSI object-oriented gadget system |
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| [input_events.md](input_events.md) | InputEvent, input.device, commodities |
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| [intuition_base.md](intuition_base.md) | IntuitionBase — library versioning, global state fields, ViewLord, LockIBase, function overview |
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| [screens.md](screens.md) | Screens — Copper mechanics, display modes (OCS/ECS/AGA/RTG), dragging, resolution tables |
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| [windows.md](windows.md) | Windows — WA_ tags, refresh modes, window types, coordinate system, lifecycle |
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| [gadgets.md](gadgets.md) | Gadgets — GadTools creation, raw struct Gadget, prop/string gadgets, runtime updates |
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| [menus.md](menus.md) | Menus — GadTools NewMenu, event handling, multi-select, checkmarks, keyboard shortcuts |
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| [requesters.md](requesters.md) | Requesters — EasyRequest, ASL file/font/screenmode dialogs, non-blocking pattern |
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| [idcmp.md](idcmp.md) | IDCMP — event architecture, class reference, shared ports, antipatterns, use-case cookbook |
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| [boopsi.md](boopsi.md) | BOOPSI — OOP dispatcher model, ICA interconnection, custom class tutorial, class hierarchy |
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| [input_events.md](input_events.md) | Input Events — handler chain, QoS/priority, Commodities, latency analysis, game input |
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| **[frameworks/](frameworks/)** | **GUI Frameworks: MUI, ReAction, BGUI** |
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---
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@ -1,101 +1,505 @@
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[← Home](../README.md) · [Intuition](README.md)
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# BOOPSI — Basic Object-Oriented Programming System
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# BOOPSI — Basic Object-Oriented Programming System for Intuition
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## Overview
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## What Is BOOPSI?
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BOOPSI is AmigaOS's class-based object system for Intuition gadgets and images. Objects receive messages via `DoMethod()` and support inheritance and notification.
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BOOPSI is AmigaOS's built-in object-oriented framework for creating reusable, interconnectable UI components. Introduced in OS 2.0 (1990), it predates Java, Qt's signal/slot system, and COM — yet implements many of the same patterns: **inheritance, encapsulation, message-based dispatch, and reactive property binding**.
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BOOPSI is the foundation on which all modern Amiga GUI frameworks are built:
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```mermaid
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graph TB
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BOOPSI["BOOPSI<br/>(rootclass)"] --> GADGET["gadgetclass"]
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BOOPSI --> IMAGE["imageclass"]
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BOOPSI --> IC["icclass / modelclass"]
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GADGET --> PROP["propgclass<br/>(sliders)"]
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GADGET --> STR["strgclass<br/>(strings)"]
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GADGET --> BUTTON["buttongclass"]
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GADGET --> FRBUT["frbuttongclass"]
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GADGET --> GROUP["groupgclass"]
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GADGET --> CUSTOM["Your Custom Class"]
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IMAGE --> FRAME["frameiclass"]
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IMAGE --> FILL["fillrectclass"]
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IMAGE --> SYSI["sysiclass<br/>(system images)"]
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IC --> MODEL["modelclass"]
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style BOOPSI fill:#e8f4fd,stroke:#2196f3,color:#333
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style CUSTOM fill:#fff3e0,stroke:#ff9800,color:#333
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```
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### Why BOOPSI Matters
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| Problem | Before BOOPSI | With BOOPSI |
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|---|---|---|
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| Custom gadgets | Rewrite rendering, hit-testing, state from scratch | Inherit from `gadgetclass` — get all behavior free |
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| Gadget communication | Application must manually shuttle values between gadgets | ICA interconnection — gadgets notify each other directly |
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| Consistent look | Every app draws gadgets differently | Inherit standard imagery and behavior |
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| Extensibility | Requires source code modification | Subclass and override only what you need |
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---
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## Core Methods
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## Core Concepts
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| Method | Description |
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|---|---|
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| `OM_NEW` | Create new object |
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| `OM_DISPOSE` | Destroy object |
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| `OM_SET` | Set attributes |
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| `OM_GET` | Get attributes |
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| `OM_UPDATE` | Attribute changed notification |
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| `OM_NOTIFY` | Send notification to targets |
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| `GM_RENDER` | Render the gadget |
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| `GM_GOACTIVE` | Gadget activated by user |
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| `GM_HANDLEINPUT` | Process input while active |
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| `GM_GOINACTIVE` | Gadget deactivated |
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### 1. Classes, Objects, and Methods
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---
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| Concept | Amiga BOOPSI | C++ Analog | Qt Analog |
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|---|---|---|---|
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| **Class** | `struct IClass` | `class` definition | `QObject` subclass |
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| **Object** | `Object *` (opaque) | Class instance | `QObject *` |
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| **Method** | `DoMethod(obj, MethodID, ...)` | `obj->method()` | `QMetaObject::invokeMethod()` |
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| **Attribute** | `SetAttrs(obj, TAG_ID, value)` | `obj->setX(val)` | `obj->setProperty("x", val)` |
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| **Superclass** | `DoSuperMethod(cl, obj, msg)` | Base class call | `QObject::event()` chain |
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| **Instance data** | `INST_DATA(cl, obj)` | `this->member` | `d_ptr` (Pimpl) |
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| **Interconnection** | `ICA_TARGET` + `ICA_MAP` | Observer pattern | `connect(signal, slot)` |
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## Built-in Classes
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### 2. The Dispatcher
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| Class | Description |
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|---|---|
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| `rootclass` | Base class for all BOOPSI objects |
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| `gadgetclass` | Base gadget class |
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| `imageclass` | Base image class |
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| `strgclass` | String entry gadget |
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| `buttongclass` | Button gadget |
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| `propgclass` | Proportional slider |
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| `groupgclass` | Group container |
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| `frbuttonclass` | Framed button |
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| `frameiclass` | Frame image |
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| `sysiclass` | System images (checkmark, etc.) |
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| `icclass` | Interconnection (maps attributes) |
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| `modelclass` | Model for MVC pattern |
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---
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## Creating and Using Objects
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Every class has a single **dispatcher function** — the equivalent of a virtual method table compressed into a switch statement:
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```c
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Object *button = NewObject(NULL, "frbuttonclass",
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GA_Left, 20,
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GA_Top, 40,
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GA_Width, 100,
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GA_Height, 20,
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GA_Text, "Click Me",
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GA_ID, 42,
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ULONG MyDispatcher(struct IClass *cl, Object *obj, Msg msg)
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{
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switch (msg->MethodID)
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{
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case OM_NEW: return MyNew(cl, obj, (struct opSet *)msg);
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case OM_DISPOSE: return MyDispose(cl, obj, msg);
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case OM_SET: return MySet(cl, obj, (struct opSet *)msg);
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case OM_GET: return MyGet(cl, obj, (struct opGet *)msg);
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case OM_UPDATE: return MySet(cl, obj, (struct opSet *)msg);
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default: return DoSuperMethodA(cl, obj, msg);
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}
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}
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```
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### 3. Method Dispatch Flow
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```mermaid
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sequenceDiagram
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participant App as Application
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participant Obj as Object
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participant Disp as Dispatcher
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participant Super as Superclass
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App->>Obj: DoMethod(obj, OM_SET, tags)
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Obj->>Disp: Dispatcher(cl, obj, msg)
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Disp->>Disp: Handle known attributes
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Disp->>Super: DoSuperMethodA(cl, obj, msg)
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Super-->>Disp: Return value
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Disp-->>App: Return value
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```
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---
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## Standard Methods
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### Object Lifecycle
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| Method | Message Struct | When Called | Your Job |
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|---|---|---|---|
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| `OM_NEW` | `struct opSet` | Object creation (`NewObject()`) | Allocate resources, parse initial tags, call super first |
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| `OM_DISPOSE` | `Msg` (base) | Object destruction (`DisposeObject()`) | Free your resources, then call super |
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### Attribute Access
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| Method | Message Struct | When Called | Your Job |
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|---|---|---|---|
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| `OM_SET` | `struct opSet` | `SetAttrs()` / `SetGadgetAttrs()` | Parse tag list, update internal state, notify if changed |
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| `OM_GET` | `struct opGet` | `GetAttr()` | Check `opg_AttrID`, store value in `*opg_Storage` |
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| `OM_UPDATE` | `struct opUpdate` | ICA notification from another object | Same as OM_SET, but check `opu_Flags` for interim updates |
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| `OM_NOTIFY` | `struct opUpdate` | Internal — trigger notifications to ICA targets | Called by your OM_SET handler when attributes change |
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### Gadget-Specific Methods
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| Method | When Called | Your Job |
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|---|---|---|
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| `GM_RENDER` | Intuition needs gadget redrawn | Draw the gadget using the provided `GadgetInfo` |
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| `GM_HITTEST` | Mouse click — is it inside your gadget? | Return `GMR_GADGETHIT` or 0 |
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| `GM_GOACTIVE` | Gadget becomes active (clicked) | Begin interaction; return `GMR_MEACTIVE` to stay active |
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| `GM_HANDLEINPUT` | Mouse/key events while active | Process input; return `GMR_MEACTIVE`, `GMR_NOREUSE`, or `GMR_REUSE` |
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| `GM_GOINACTIVE` | Gadget deactivated | Clean up interaction state |
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---
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## Creating Objects
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### Using Built-in Classes
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```c
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/* Create a proportional gadget (slider) */
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Object *slider = NewObject(NULL, "propgclass",
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GA_ID, 1,
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GA_Left, 20,
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GA_Top, 40,
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GA_Width, 200,
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GA_Height, 16,
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GA_RelVerify, TRUE,
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PGA_Freedom, FREEHORIZ,
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PGA_Total, 100,
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PGA_Top, 0,
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PGA_Visible, 10,
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TAG_DONE);
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AddGadget(win, (struct Gadget *)button, -1);
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RefreshGadgets((struct Gadget *)button, win, NULL);
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/* Add to window */
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AddGadget(win, (struct Gadget *)slider, -1);
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RefreshGList((struct Gadget *)slider, win, NULL, 1);
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/* Set attribute: */
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SetGadgetAttrs((struct Gadget *)button, win, NULL,
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GA_Disabled, TRUE,
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/* Read current position */
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LONG pos;
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GetAttr(PGA_Top, slider, (ULONG *)&pos);
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/* Update position */
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SetGadgetAttrs((struct Gadget *)slider, win, NULL,
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PGA_Top, 50,
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TAG_DONE);
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/* Get attribute: */
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ULONG value;
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GetAttr(GA_Disabled, button, &value);
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/* Destroy */
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RemoveGadget(win, (struct Gadget *)slider);
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DisposeObject(slider);
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```
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/* Cleanup: */
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RemoveGadget(win, (struct Gadget *)button);
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DisposeObject(button);
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### Using a Class Pointer
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```c
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/* When you have a Class * instead of a name */
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struct IClass *myClass = MakeMyClass();
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Object *obj = NewObject(myClass, NULL,
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MY_Attribute, value,
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TAG_DONE);
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```
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---
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## ICA — Interconnection Architecture
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The most powerful BOOPSI feature: **reactive data binding between objects** without application intervention.
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### Direct Connection (icclass)
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```mermaid
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graph LR
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SLIDER["Slider<br/>(propgclass)"] -->|"PGA_Top changes"| IC["icclass<br/>(mapper)"]
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IC -->|"Mapped attribute"| READOUT["Number Display<br/>(strgclass)"]
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style IC fill:#e8f4fd,stroke:#2196f3,color:#333
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```
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```c
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/* Map slider position to string gadget value */
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struct TagItem sliderToReadout[] = {
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{ PGA_Top, STRINGA_LongVal },
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{ TAG_DONE, 0 }
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};
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/* Create interconnection */
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SetAttrs(slider,
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ICA_TARGET, readout, /* Target object */
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ICA_MAP, sliderToReadout, /* Attribute mapping */
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TAG_DONE);
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/* Now when slider moves, readout updates automatically! */
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```
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### Broadcast (modelclass)
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For one-to-many notifications:
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```c
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/* Create a model (data source) */
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Object *model = NewObject(NULL, "modelclass",
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ICA_TARGET, ICTARGET_IDCMP, /* Also notify application */
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TAG_DONE);
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/* Add multiple views */
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DoMethod(model, OM_ADDMEMBER, slider);
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DoMethod(model, OM_ADDMEMBER, readout);
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DoMethod(model, OM_ADDMEMBER, gauge);
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/* Update the model — all views update automatically */
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SetAttrs(model, MY_VALUE, 42, TAG_DONE);
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```
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### ICA → IDCMP Bridge
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When `ICA_TARGET` is `ICTARGET_IDCMP`, attribute changes generate `IDCMP_IDCMPUPDATE` messages:
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```c
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SetAttrs(slider,
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ICA_TARGET, ICTARGET_IDCMP,
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TAG_DONE);
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/* In event loop: */
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case IDCMP_IDCMPUPDATE:
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{
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struct TagItem *tags = (struct TagItem *)msg->IAddress;
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LONG value = GetTagData(PGA_Top, 0, tags);
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UpdateApplication(value);
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break;
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}
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```
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---
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## Writing a Custom Class
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```c
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Class *myclass = MakeClass(NULL, "gadgetclass", NULL,
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sizeof(struct MyData), 0);
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myclass->cl_Dispatcher.h_Entry = (HOOKFUNC)myDispatcher;
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### Step 1: Define Instance Data
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ULONG myDispatcher(Class *cl, Object *o, Msg msg) {
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switch (msg->MethodID) {
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case OM_NEW: return myNew(cl, o, (struct opSet *)msg);
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case OM_DISPOSE: return myDispose(cl, o, msg);
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case GM_RENDER: return myRender(cl, o, (struct gpRender *)msg);
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default: return DoSuperMethodA(cl, o, msg);
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```c
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struct MyGadgetData {
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LONG value;
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LONG minVal;
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LONG maxVal;
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UWORD fgPen;
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UWORD bgPen;
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BOOL active;
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};
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```
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### Step 2: Implement the Dispatcher
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```c
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ULONG MyGadgetDispatcher(struct IClass *cl, Object *obj, Msg msg)
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{
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struct MyGadgetData *data;
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switch (msg->MethodID)
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{
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case OM_NEW:
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{
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/* Let superclass create the object first */
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Object *newObj = (Object *)DoSuperMethodA(cl, obj, msg);
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if (!newObj) return 0;
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data = INST_DATA(cl, newObj);
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data->value = 0;
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data->minVal = 0;
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data->maxVal = 100;
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data->fgPen = 1;
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data->bgPen = 0;
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data->active = FALSE;
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/* Parse initial tags */
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struct TagItem *tags = ((struct opSet *)msg)->ops_AttrList;
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struct TagItem *tag;
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while ((tag = NextTagItem(&tags)))
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{
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switch (tag->ti_Tag)
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{
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case MYGA_Value: data->value = tag->ti_Data; break;
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case MYGA_Min: data->minVal = tag->ti_Data; break;
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case MYGA_Max: data->maxVal = tag->ti_Data; break;
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}
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}
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return (ULONG)newObj;
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}
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case OM_SET:
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case OM_UPDATE:
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{
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data = INST_DATA(cl, obj);
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struct TagItem *tags = ((struct opSet *)msg)->ops_AttrList;
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struct TagItem *tag;
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BOOL refresh = FALSE;
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while ((tag = NextTagItem(&tags)))
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{
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switch (tag->ti_Tag)
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{
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case MYGA_Value:
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if (data->value != tag->ti_Data)
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{
|
||||
data->value = tag->ti_Data;
|
||||
refresh = TRUE;
|
||||
}
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
/* Propagate to superclass */
|
||||
DoSuperMethodA(cl, obj, msg);
|
||||
|
||||
/* Notify ICA targets of changes */
|
||||
if (refresh)
|
||||
{
|
||||
struct TagItem notify[] = {
|
||||
{ MYGA_Value, data->value },
|
||||
{ TAG_DONE, 0 }
|
||||
};
|
||||
DoSuperMethod(cl, obj, OM_NOTIFY, notify,
|
||||
((struct opSet *)msg)->ops_GInfo, 0);
|
||||
}
|
||||
|
||||
return refresh;
|
||||
}
|
||||
|
||||
case OM_GET:
|
||||
{
|
||||
data = INST_DATA(cl, obj);
|
||||
struct opGet *opg = (struct opGet *)msg;
|
||||
|
||||
switch (opg->opg_AttrID)
|
||||
{
|
||||
case MYGA_Value:
|
||||
*opg->opg_Storage = data->value;
|
||||
return TRUE;
|
||||
default:
|
||||
return DoSuperMethodA(cl, obj, msg);
|
||||
}
|
||||
}
|
||||
|
||||
case GM_RENDER:
|
||||
{
|
||||
data = INST_DATA(cl, obj);
|
||||
struct gpRender *gpr = (struct gpRender *)msg;
|
||||
struct RastPort *rp = gpr->gpr_RPort;
|
||||
struct Gadget *g = (struct Gadget *)obj;
|
||||
|
||||
/* Draw the gadget */
|
||||
SetAPen(rp, data->bgPen);
|
||||
RectFill(rp, g->LeftEdge, g->TopEdge,
|
||||
g->LeftEdge + g->Width - 1,
|
||||
g->TopEdge + g->Height - 1);
|
||||
|
||||
/* Draw value bar */
|
||||
LONG barWidth = (data->value - data->minVal) *
|
||||
g->Width / (data->maxVal - data->minVal);
|
||||
SetAPen(rp, data->fgPen);
|
||||
RectFill(rp, g->LeftEdge, g->TopEdge,
|
||||
g->LeftEdge + barWidth - 1,
|
||||
g->TopEdge + g->Height - 1);
|
||||
|
||||
return TRUE;
|
||||
}
|
||||
|
||||
case GM_HITTEST:
|
||||
{
|
||||
/* Simple rectangular hit test — already handled by gadgetclass */
|
||||
return GMR_GADGETHIT;
|
||||
}
|
||||
|
||||
default:
|
||||
return DoSuperMethodA(cl, obj, msg);
|
||||
}
|
||||
}
|
||||
```
|
||||
|
||||
### Step 3: Register the Class
|
||||
|
||||
```c
|
||||
struct IClass *MyGadgetClass = NULL;
|
||||
|
||||
struct IClass *InitMyGadgetClass(void)
|
||||
{
|
||||
MyGadgetClass = MakeClass(
|
||||
NULL, /* Public name (NULL = private) */
|
||||
"gadgetclass", /* Superclass name */
|
||||
NULL, /* Superclass pointer (alt.) */
|
||||
sizeof(struct MyGadgetData), /* Instance data size */
|
||||
0 /* Flags */
|
||||
);
|
||||
|
||||
if (MyGadgetClass)
|
||||
MyGadgetClass->cl_Dispatcher.h_Entry = (HOOKFUNC)MyGadgetDispatcher;
|
||||
|
||||
return MyGadgetClass;
|
||||
}
|
||||
|
||||
/* For a public class (usable by other programs): */
|
||||
struct IClass *pubClass = MakeClass(
|
||||
"mygadget.class", /* Public name */
|
||||
"gadgetclass",
|
||||
NULL,
|
||||
sizeof(struct MyGadgetData),
|
||||
0
|
||||
);
|
||||
AddClass(pubClass); /* Register with Intuition */
|
||||
```
|
||||
|
||||
### Step 4: Use Your Class
|
||||
|
||||
```c
|
||||
struct IClass *cl = InitMyGadgetClass();
|
||||
|
||||
Object *gauge = NewObject(cl, NULL,
|
||||
GA_Left, 20,
|
||||
GA_Top, 60,
|
||||
GA_Width, 200,
|
||||
GA_Height, 20,
|
||||
MYGA_Value, 50,
|
||||
MYGA_Min, 0,
|
||||
MYGA_Max, 100,
|
||||
TAG_DONE);
|
||||
|
||||
/* Connect slider to gauge via ICA */
|
||||
SetAttrs(slider,
|
||||
ICA_TARGET, gauge,
|
||||
ICA_MAP, sliderToGauge,
|
||||
TAG_DONE);
|
||||
```
|
||||
|
||||
---
|
||||
|
||||
## Built-in Class Hierarchy
|
||||
|
||||
| Class | Superclass | Purpose |
|
||||
|---|---|---|
|
||||
| `rootclass` | — | Base of all BOOPSI objects |
|
||||
| `imageclass` | `rootclass` | Base for all images |
|
||||
| `frameiclass` | `imageclass` | Recessed/raised 3D frames |
|
||||
| `sysiclass` | `imageclass` | System images (arrows, checkmarks) |
|
||||
| `fillrectclass` | `imageclass` | Filled rectangles with patterns |
|
||||
| `gadgetclass` | `rootclass` | Base for all gadgets |
|
||||
| `propgclass` | `gadgetclass` | Proportional (slider) gadgets |
|
||||
| `strgclass` | `gadgetclass` | String input gadgets |
|
||||
| `buttongclass` | `gadgetclass` | Push buttons |
|
||||
| `frbuttongclass` | `gadgetclass` | Framed push buttons |
|
||||
| `groupgclass` | `gadgetclass` | Container for gadget groups |
|
||||
| `icclass` | `rootclass` | Interconnection (1-to-1 binding) |
|
||||
| `modelclass` | `icclass` | Interconnection (1-to-many broadcast) |
|
||||
|
||||
---
|
||||
|
||||
## Pitfalls
|
||||
|
||||
### 1. Forgetting DoSuperMethodA
|
||||
|
||||
If you handle `OM_NEW` without calling `DoSuperMethodA()` first, the object is never properly allocated. If you handle `OM_DISPOSE` without calling super last, the base class never frees its memory.
|
||||
|
||||
### 2. OM_SET Without OM_NOTIFY
|
||||
|
||||
If you update internal state in `OM_SET` but don't call `OM_NOTIFY`, ICA connections are silently broken — connected objects never update.
|
||||
|
||||
### 3. Wrong INST_DATA Timing
|
||||
|
||||
In `OM_NEW`, you must call `DoSuperMethodA()` **before** `INST_DATA()`. The superclass allocates the memory that `INST_DATA()` points to.
|
||||
|
||||
### 4. Modifying Gadget Attrs Without Window
|
||||
|
||||
`SetGadgetAttrs()` requires a window pointer to trigger a visual refresh. `SetAttrs()` alone updates internal state but doesn't redraw.
|
||||
|
||||
### 5. ICA Map Memory Management
|
||||
|
||||
The `ICA_MAP` tag list must persist for the lifetime of the connection. If you pass a stack-allocated array, it becomes garbage when the function returns.
|
||||
|
||||
---
|
||||
|
||||
## Best Practices
|
||||
|
||||
1. **Always call `DoSuperMethodA()`** for methods you partially handle — let the superclass do its job
|
||||
2. **Use `NextTagItem()`** to iterate tag lists — it handles `TAG_SKIP`, `TAG_MORE`, etc.
|
||||
3. **Send `OM_NOTIFY`** whenever a settable attribute changes — this drives ICA
|
||||
4. **Keep dispatch fast** — complex rendering should be deferred to `GM_RENDER`
|
||||
5. **Use `ICA_TARGET = ICTARGET_IDCMP`** when the application needs to know about changes
|
||||
6. **Allocate `ICA_MAP` arrays statically** or in instance data — not on the stack
|
||||
7. **Private classes** (NULL name) are simpler and sufficient for most applications
|
||||
8. **Use `modelclass`** for MVC patterns — it's the Amiga's built-in observer
|
||||
|
||||
---
|
||||
|
||||
## References
|
||||
|
||||
- NDK39: `intuition/classusr.h`, `intuition/classes.h`
|
||||
- ADCD 2.1: `NewObject`, `DisposeObject`, `SetAttrs`, `GetAttr`, `DoMethod`
|
||||
- NDK 3.9: `intuition/classes.h`, `intuition/classusr.h`, `intuition/gadgetclass.h`, `intuition/imageclass.h`, `intuition/icclass.h`
|
||||
- ADCD 2.1: `NewObject()`, `DisposeObject()`, `SetAttrs()`, `GetAttr()`, `DoMethod()`
|
||||
- AmigaOS Reference Manual (RKRM): Libraries, Chapter 8 — BOOPSI
|
||||
- See also: [Gadgets](gadgets.md), [MUI Framework](frameworks/mui/README.md)
|
||||
|
|
|
|||
|
|
@ -1,107 +1,403 @@
|
|||
[← Home](../README.md) · [Intuition](README.md)
|
||||
|
||||
# Gadgets — GadTools and BOOPSI
|
||||
# Gadgets
|
||||
|
||||
## Overview
|
||||
## What Is a Gadget?
|
||||
|
||||
Intuition gadgets are the UI controls: buttons, string fields, sliders, checkboxes, listviews, etc. OS 2.0+ provides **GadTools** (high-level toolkit) and **BOOPSI** (object-oriented framework).
|
||||
A gadget is Intuition's fundamental interactive UI element — the Amiga equivalent of a widget, control, or component. Every button, checkbox, slider, text field, and scrollbar in an Amiga application is a gadget. Gadgets handle their own rendering, hit-testing, and state management, delivering results to the application via [IDCMP](idcmp.md) messages.
|
||||
|
||||
The gadget system evolved through three major generations:
|
||||
|
||||
| Generation | Era | API | Key Feature |
|
||||
|---|---|---|---|
|
||||
| **Raw Intuition** | 1985 (OS 1.x) | `struct Gadget` + manual imagery | Full control, maximum boilerplate |
|
||||
| **GadTools** | 1990 (OS 2.0) | `CreateGadget()` + `NewGadget` | Standard OS look-and-feel with minimal code |
|
||||
| **[BOOPSI](boopsi.md)** | 1990 (OS 2.0) | `NewObject()` + OOP dispatchers | Object-oriented, interconnectable, extensible |
|
||||
|
||||
Most applications should use **GadTools** for standard UI or **BOOPSI** for custom behavior. Raw Intuition gadgets are only necessary for OS 1.x compatibility or extreme customization.
|
||||
|
||||
---
|
||||
|
||||
## GadTools Gadget Types
|
||||
## Gadget Types
|
||||
|
||||
| Kind | Constant | Description |
|
||||
|---|---|---|
|
||||
| Button | `BUTTON_KIND` | Simple push button |
|
||||
| Checkbox | `CHECKBOX_KIND` | Toggle on/off |
|
||||
| Integer | `INTEGER_KIND` | Numeric entry field |
|
||||
| Listview | `LISTVIEW_KIND` | Scrollable list |
|
||||
| MX | `MX_KIND` | Mutually exclusive (radio buttons) |
|
||||
| Number | `NUMBER_KIND` | Read-only number display |
|
||||
| Cycle | `CYCLE_KIND` | Pop-up cycle selector |
|
||||
| Palette | `PALETTE_KIND` | Colour picker |
|
||||
| Scroller | `SCROLLER_KIND` | Scroll bar |
|
||||
| Slider | `SLIDER_KIND` | Value slider |
|
||||
| String | `STRING_KIND` | Text entry field |
|
||||
| Text | `TEXT_KIND` | Read-only text display |
|
||||
### System Gadgets
|
||||
|
||||
Built into every window — controlled by `WA_Flags`:
|
||||
|
||||
| Gadget | Flag | IDCMP Event | Description |
|
||||
|---|---|---|---|
|
||||
| Close | `WFLG_CLOSEGADGET` | `IDCMP_CLOSEWINDOW` | "×" button — window close request |
|
||||
| Depth | `WFLG_DEPTHGADGET` | — (handled by Intuition) | Front/back toggle |
|
||||
| Zoom | `WFLG_HASZOOM` | — | Alternate-size toggle (OS 2.0+) |
|
||||
| Drag | `WFLG_DRAGBAR` | — | Title bar drag area |
|
||||
| Size | `WFLG_SIZEGADGET` | `IDCMP_NEWSIZE` | Resize handle |
|
||||
|
||||
### Application Gadgets
|
||||
|
||||
Created by the application and attached to windows:
|
||||
|
||||
| Type | GadTools Kind | Description | IDCMP |
|
||||
|---|---|---|---|
|
||||
| **Button** | `BUTTON_KIND` | Click action | `IDCMP_GADGETUP` |
|
||||
| **Checkbox** | `CHECKBOX_KIND` | Boolean toggle | `IDCMP_GADGETUP` |
|
||||
| **Cycle** | `CYCLE_KIND` | Drop-down selector (cycles through options) | `IDCMP_GADGETUP` |
|
||||
| **Integer** | `INTEGER_KIND` | Numeric text field | `IDCMP_GADGETUP` |
|
||||
| **ListView** | `LISTVIEW_KIND` | Scrollable list of items | `IDCMP_GADGETUP` |
|
||||
| **MX** (Mutual Exclude) | `MX_KIND` | Radio button group | `IDCMP_GADGETUP` |
|
||||
| **Number** | `NUMBER_KIND` | Read-only numeric display | — |
|
||||
| **Palette** | `PALETTE_KIND` | Color picker from screen palette | `IDCMP_GADGETUP` |
|
||||
| **Scroller** | `SCROLLER_KIND` | Scrollbar | `IDCMP_GADGETUP` / `MOUSEMOVE` |
|
||||
| **Slider** | `SLIDER_KIND` | Horizontal/vertical value slider | `IDCMP_GADGETUP` / `MOUSEMOVE` |
|
||||
| **String** | `STRING_KIND` | Text input field | `IDCMP_GADGETUP` |
|
||||
| **Text** | `TEXT_KIND` | Read-only text display | — |
|
||||
|
||||
---
|
||||
|
||||
## Creating a GadTools Layout
|
||||
## GadTools — Standard Gadget Creation (OS 2.0+)
|
||||
|
||||
### Setup
|
||||
|
||||
GadTools requires a **VisualInfo** handle (ties gadgets to a specific screen's look):
|
||||
|
||||
```c
|
||||
#include <libraries/gadtools.h>
|
||||
#include <proto/gadtools.h>
|
||||
|
||||
struct Library *GadToolsBase = OpenLibrary("gadtools.library", 39);
|
||||
struct Screen *scr = LockPubScreen(NULL);
|
||||
APTR vi = GetVisualInfo(scr, TAG_DONE);
|
||||
```
|
||||
|
||||
### Creating a Gadget List
|
||||
|
||||
GadTools gadgets are created in a **linked list** using a context pointer:
|
||||
|
||||
```c
|
||||
struct Gadget *glist = NULL;
|
||||
struct NewGadget ng;
|
||||
struct Gadget *gad = CreateContext(&glist);
|
||||
struct Gadget *gad;
|
||||
|
||||
ng.ng_LeftEdge = 20;
|
||||
ng.ng_TopEdge = 30;
|
||||
ng.ng_Width = 100;
|
||||
ng.ng_Height = 14;
|
||||
ng.ng_GadgetText = "OK";
|
||||
ng.ng_GadgetID = 1;
|
||||
ng.ng_VisualInfo = vi;
|
||||
ng.ng_Flags = 0;
|
||||
ng.ng_TextAttr = NULL;
|
||||
/* Initialize the context — creates a hidden "anchor" gadget */
|
||||
gad = CreateContext(&glist);
|
||||
|
||||
gad = CreateGadget(BUTTON_KIND, gad, &ng, TAG_DONE);
|
||||
/* Define gadget layout */
|
||||
struct NewGadget ng = {
|
||||
.ng_LeftEdge = 20,
|
||||
.ng_TopEdge = 30,
|
||||
.ng_Width = 200,
|
||||
.ng_Height = 14,
|
||||
.ng_GadgetText = "Name:",
|
||||
.ng_TextAttr = &topaz8,
|
||||
.ng_GadgetID = GAD_NAME,
|
||||
.ng_Flags = PLACETEXT_LEFT,
|
||||
.ng_VisualInfo = vi,
|
||||
};
|
||||
|
||||
ng.ng_TopEdge += 20;
|
||||
ng.ng_GadgetText = "Cancel";
|
||||
ng.ng_GadgetID = 2;
|
||||
gad = CreateGadget(BUTTON_KIND, gad, &ng, TAG_DONE);
|
||||
|
||||
/* Open window with gadgets: */
|
||||
struct Window *win = OpenWindowTags(NULL,
|
||||
WA_Gadgets, glist,
|
||||
WA_IDCMP, IDCMP_GADGETUP | IDCMP_CLOSEWINDOW | BUTTONIDCMP,
|
||||
/* ... */
|
||||
/* String gadget */
|
||||
gad = CreateGadget(STRING_KIND, gad, &ng,
|
||||
GTST_MaxChars, 64,
|
||||
GTST_String, "Default",
|
||||
TAG_DONE);
|
||||
|
||||
/* Event loop: */
|
||||
/* on IDCMP_GADGETUP: */
|
||||
/* struct Gadget *gad = (struct Gadget *)imsg->IAddress; */
|
||||
/* switch (gad->GadgetID) { case 1: ... case 2: ... } */
|
||||
/* Button below it */
|
||||
ng.ng_TopEdge += 20;
|
||||
ng.ng_GadgetText = "OK";
|
||||
ng.ng_GadgetID = GAD_OK;
|
||||
ng.ng_Flags = PLACETEXT_IN;
|
||||
|
||||
/* Cleanup: */
|
||||
gad = CreateGadget(BUTTON_KIND, gad, &ng, TAG_DONE);
|
||||
|
||||
/* Attach to window */
|
||||
struct Window *win = OpenWindowTags(NULL,
|
||||
WA_Title, "GadTools Demo",
|
||||
WA_Gadgets, glist, /* Attach gadget list */
|
||||
WA_IDCMP, IDCMP_CLOSEWINDOW | IDCMP_GADGETUP |
|
||||
IDCMP_REFRESHWINDOW,
|
||||
WA_Flags, WFLG_CLOSEGADGET | WFLG_DRAGBAR |
|
||||
WFLG_DEPTHGADGET | WFLG_ACTIVATE |
|
||||
WFLG_SMART_REFRESH,
|
||||
TAG_DONE);
|
||||
|
||||
/* Render gadget borders (required for GadTools!) */
|
||||
GT_RefreshWindow(win, NULL);
|
||||
```
|
||||
|
||||
### Event Handling
|
||||
|
||||
```c
|
||||
struct IntuiMessage *msg;
|
||||
while ((msg = GT_GetIMsg(win->UserPort)))
|
||||
{
|
||||
ULONG class = msg->Class;
|
||||
UWORD code = msg->Code;
|
||||
struct Gadget *gad = (struct Gadget *)msg->IAddress;
|
||||
|
||||
GT_ReplyIMsg(msg);
|
||||
|
||||
switch (class)
|
||||
{
|
||||
case IDCMP_GADGETUP:
|
||||
switch (gad->GadgetID)
|
||||
{
|
||||
case GAD_NAME:
|
||||
{
|
||||
/* Read string value */
|
||||
STRPTR name;
|
||||
GT_GetGadgetAttrs(gad, win, NULL,
|
||||
GTST_String, &name, TAG_DONE);
|
||||
Printf("Name: %s\n", name);
|
||||
break;
|
||||
}
|
||||
case GAD_OK:
|
||||
running = FALSE;
|
||||
break;
|
||||
}
|
||||
break;
|
||||
|
||||
case IDCMP_REFRESHWINDOW:
|
||||
GT_BeginRefresh(win);
|
||||
GT_EndRefresh(win, TRUE);
|
||||
break;
|
||||
}
|
||||
}
|
||||
```
|
||||
|
||||
### Cleanup
|
||||
|
||||
```c
|
||||
/* Order matters: window first, then gadgets, then visual info */
|
||||
CloseWindow(win);
|
||||
FreeGadgets(glist);
|
||||
FreeVisualInfo(vi);
|
||||
UnlockPubScreen(NULL, scr);
|
||||
CloseLibrary(GadToolsBase);
|
||||
```
|
||||
|
||||
---
|
||||
|
||||
## BOOPSI (Basic Object-Oriented Programming System for Intuition)
|
||||
## Updating Gadget State at Runtime
|
||||
|
||||
BOOPSI provides class-based gadgets with message dispatch:
|
||||
### GadTools Gadgets
|
||||
|
||||
```c
|
||||
/* Create a BOOPSI string gadget: */
|
||||
Object *strObj = NewObject(NULL, "strgclass",
|
||||
GA_Left, 20,
|
||||
GA_Top, 50,
|
||||
GA_Width, 200,
|
||||
GA_Height, 14,
|
||||
GA_ID, 3,
|
||||
STRINGA_Buffer, myBuffer,
|
||||
STRINGA_MaxChars, 64,
|
||||
/* Update a slider value */
|
||||
GT_SetGadgetAttrs(sliderGad, win, NULL,
|
||||
GTSL_Level, 75,
|
||||
TAG_DONE);
|
||||
|
||||
/* Add to window: */
|
||||
AddGadget(win, (struct Gadget *)strObj, -1);
|
||||
RefreshGadgets((struct Gadget *)strObj, win, NULL);
|
||||
/* Disable a button */
|
||||
GT_SetGadgetAttrs(okGad, win, NULL,
|
||||
GA_Disabled, TRUE,
|
||||
TAG_DONE);
|
||||
|
||||
/* Cleanup: */
|
||||
RemoveGadget(win, (struct Gadget *)strObj);
|
||||
DisposeObject(strObj);
|
||||
/* Read current value */
|
||||
LONG level;
|
||||
GT_GetGadgetAttrs(sliderGad, win, NULL,
|
||||
GTSL_Level, &level,
|
||||
TAG_DONE);
|
||||
```
|
||||
|
||||
### Raw Intuition Gadgets
|
||||
|
||||
For non-GadTools gadgets, you must manually remove/re-add to avoid rendering glitches:
|
||||
|
||||
```c
|
||||
/* Remove gadget from window */
|
||||
UWORD pos = RemoveGadget(win, myGadget);
|
||||
|
||||
/* Modify gadget fields */
|
||||
myGadget->Flags |= GFLG_DISABLED;
|
||||
|
||||
/* Re-add at same position */
|
||||
AddGadget(win, myGadget, pos);
|
||||
|
||||
/* Refresh the display */
|
||||
RefreshGList(myGadget, win, NULL, 1);
|
||||
```
|
||||
|
||||
---
|
||||
|
||||
## Raw Intuition Gadgets (struct Gadget)
|
||||
|
||||
For cases where GadTools or BOOPSI are insufficient — direct hardware-level control:
|
||||
|
||||
### struct Gadget
|
||||
|
||||
```c
|
||||
struct Gadget {
|
||||
struct Gadget *NextGadget; /* Linked list */
|
||||
WORD LeftEdge, TopEdge;
|
||||
WORD Width, Height;
|
||||
UWORD Flags; /* GFLG_* */
|
||||
UWORD Activation; /* GACT_* */
|
||||
UWORD GadgetType; /* GTYP_* */
|
||||
APTR GadgetRender; /* Image or Border for normal state */
|
||||
APTR SelectRender; /* Image or Border for selected state */
|
||||
struct IntuiText *GadgetText; /* Label */
|
||||
LONG MutualExclude;
|
||||
APTR SpecialInfo; /* StringInfo, PropInfo, etc. */
|
||||
UWORD GadgetID; /* Application-defined ID */
|
||||
APTR UserData; /* Application-defined pointer */
|
||||
};
|
||||
```
|
||||
|
||||
### Gadget Flags (GFLG_*)
|
||||
|
||||
| Flag | Value | Description |
|
||||
|---|---|---|
|
||||
| `GFLG_GADGHCOMP` | `0x0000` | Highlight by complementing select box |
|
||||
| `GFLG_GADGHBOX` | `0x0001` | Highlight by drawing box around gadget |
|
||||
| `GFLG_GADGHIMAGE` | `0x0002` | Use `SelectRender` image when selected |
|
||||
| `GFLG_GADGHNONE` | `0x0003` | No highlighting |
|
||||
| `GFLG_GADGIMAGE` | `0x0004` | `GadgetRender` is `struct Image *`, not `struct Border *` |
|
||||
| `GFLG_RELBOTTOM` | `0x0008` | Position relative to bottom edge |
|
||||
| `GFLG_RELRIGHT` | `0x0010` | Position relative to right edge |
|
||||
| `GFLG_RELWIDTH` | `0x0020` | Width relative to window width |
|
||||
| `GFLG_RELHEIGHT` | `0x0040` | Height relative to window height |
|
||||
| `GFLG_SELECTED` | `0x0080` | Gadget is currently selected |
|
||||
| `GFLG_DISABLED` | `0x0100` | Gadget is grayed out / inactive |
|
||||
|
||||
### Activation Flags (GACT_*)
|
||||
|
||||
| Flag | Value | Description |
|
||||
|---|---|---|
|
||||
| `GACT_RELVERIFY` | `0x0001` | Send `IDCMP_GADGETUP` only if mouse released inside |
|
||||
| `GACT_IMMEDIATE` | `0x0002` | Send `IDCMP_GADGETDOWN` on press |
|
||||
| `GACT_ENDGADGET` | `0x0004` | Deactivate requester when gadget released |
|
||||
| `GACT_FOLLOWMOUSE` | `0x0008` | Report mouse while gadget is active |
|
||||
| `GACT_TOGGLESELECT` | `0x0100` | Toggle selected state on each click |
|
||||
| `GACT_LONGINT` | `0x0800` | String gadget contains a long integer |
|
||||
|
||||
### Gadget Types (GTYP_*)
|
||||
|
||||
| Type | Value | SpecialInfo | Description |
|
||||
|---|---|---|---|
|
||||
| `GTYP_BOOLGADGET` | `0x0001` | — | Simple click button |
|
||||
| `GTYP_STRGADGET` | `0x0004` | `struct StringInfo *` | Text input field |
|
||||
| `GTYP_PROPGADGET` | `0x0003` | `struct PropInfo *` | Proportional (slider/scrollbar) |
|
||||
| `GTYP_CUSTOMGADGET` | `0x0005` | Class-specific | BOOPSI custom class |
|
||||
|
||||
---
|
||||
|
||||
## Proportional (Slider) Gadgets
|
||||
|
||||
Prop gadgets are used for scrollbars and sliders. They have their own state structure:
|
||||
|
||||
```c
|
||||
struct PropInfo {
|
||||
UWORD Flags; /* AUTOKNOB, FREEHORIZ, FREEVERT */
|
||||
UWORD HorizPot; /* Horizontal position (0–0xFFFF) */
|
||||
UWORD VertPot; /* Vertical position (0–0xFFFF) */
|
||||
UWORD HorizBody; /* Horizontal knob size (0–0xFFFF) */
|
||||
UWORD VertBody; /* Vertical knob size (0–0xFFFF) */
|
||||
/* ... internal fields ... */
|
||||
};
|
||||
|
||||
/* Calculate body size for a scrollbar:
|
||||
visible = number of visible items
|
||||
total = total number of items */
|
||||
UWORD body = (visible >= total) ? MAXBODY
|
||||
: (UWORD)((ULONG)MAXBODY * visible / total);
|
||||
|
||||
/* Calculate pot (position) from current top item:
|
||||
top = first visible item index */
|
||||
UWORD pot = (total <= visible) ? 0
|
||||
: (UWORD)((ULONG)MAXPOT * top / (total - visible));
|
||||
```
|
||||
|
||||
---
|
||||
|
||||
## String Gadgets
|
||||
|
||||
Text input gadgets use `StringInfo`:
|
||||
|
||||
```c
|
||||
UBYTE buffer[128] = "Default text";
|
||||
UBYTE undoBuffer[128];
|
||||
|
||||
struct StringInfo si = {
|
||||
.Buffer = buffer,
|
||||
.UndoBuffer = undoBuffer,
|
||||
.BufferPos = 0,
|
||||
.MaxChars = sizeof(buffer),
|
||||
};
|
||||
|
||||
/* Read the result after GADGETUP: */
|
||||
Printf("User entered: %s\n", si.Buffer);
|
||||
```
|
||||
|
||||
With GadTools, this is much simpler:
|
||||
|
||||
```c
|
||||
gad = CreateGadget(STRING_KIND, gad, &ng,
|
||||
GTST_MaxChars, 128,
|
||||
GTST_String, "Default text",
|
||||
TAG_DONE);
|
||||
```
|
||||
|
||||
---
|
||||
|
||||
## Relative Positioning
|
||||
|
||||
Gadgets can be positioned relative to window edges — they automatically move when the window resizes:
|
||||
|
||||
```c
|
||||
/* Scrollbar on the right edge */
|
||||
myGadget.LeftEdge = -16; /* 16 pixels from right */
|
||||
myGadget.TopEdge = 0;
|
||||
myGadget.Width = 16;
|
||||
myGadget.Height = -16; /* Extends to 16px from bottom */
|
||||
myGadget.Flags = GFLG_RELRIGHT | GFLG_RELHEIGHT;
|
||||
```
|
||||
|
||||
| Flag | Effect |
|
||||
|---|---|
|
||||
| `GFLG_RELRIGHT` | `LeftEdge` is offset from right edge (use negative values) |
|
||||
| `GFLG_RELBOTTOM` | `TopEdge` is offset from bottom edge |
|
||||
| `GFLG_RELWIDTH` | `Width` is added to window width |
|
||||
| `GFLG_RELHEIGHT` | `Height` is added to window height |
|
||||
|
||||
---
|
||||
|
||||
## Pitfalls
|
||||
|
||||
### 1. Forgetting GT_RefreshWindow
|
||||
|
||||
GadTools gadgets won't render properly without the initial `GT_RefreshWindow(win, NULL)` call. The window appears to have no gadgets.
|
||||
|
||||
### 2. Using GetMsg Instead of GT_GetIMsg
|
||||
|
||||
GadTools internally sends messages for gadget sub-events (e.g., ListView scrolling). Using `GetMsg()` directly breaks GadTools' internal state machine.
|
||||
|
||||
### 3. Modifying Gadgets Without Remove/Add
|
||||
|
||||
Changing a raw gadget's position, flags, or imagery while it's attached to a window causes rendering corruption. Always `RemoveGadget()` → modify → `AddGadget()` → `RefreshGList()`.
|
||||
|
||||
### 4. Not Setting GACT_RELVERIFY
|
||||
|
||||
Without `GACT_RELVERIFY`, the application never receives `IDCMP_GADGETUP`. The gadget appears to "eat" clicks silently.
|
||||
|
||||
### 5. String Gadget Buffer Overrun
|
||||
|
||||
The `MaxChars` field includes the null terminator. If your buffer is 64 bytes, set `MaxChars` to 64 (not 63). The gadget handles null termination.
|
||||
|
||||
---
|
||||
|
||||
## Best Practices
|
||||
|
||||
1. **Use GadTools** for standard UI — it provides the correct OS look-and-feel automatically
|
||||
2. **Use `GT_GetIMsg()`/`GT_ReplyIMsg()`** — never mix raw `GetMsg()` with GadTools
|
||||
3. **Always call `GT_RefreshWindow()`** after opening a window with GadTools gadgets
|
||||
4. **Free in reverse order**: `CloseWindow()` → `FreeGadgets()` → `FreeVisualInfo()` → `UnlockPubScreen()`
|
||||
5. **Use `GA_Disabled`** to gray out gadgets instead of removing them — maintains layout stability
|
||||
6. **Set `PLACETEXT_LEFT/RIGHT/ABOVE`** for label placement — don't hardcode text positions
|
||||
7. **Handle `IDCMP_REFRESHWINDOW`** with `GT_BeginRefresh()`/`GT_EndRefresh()`
|
||||
8. **Give every gadget a unique `GadgetID`** — this is how you identify the source in `IDCMP_GADGETUP`
|
||||
|
||||
---
|
||||
|
||||
## References
|
||||
|
||||
- NDK39: `libraries/gadtools.h`, `intuition/classusr.h`
|
||||
- ADCD 2.1: `CreateGadget`, `CreateContext`, `GetVisualInfo`
|
||||
- NDK 3.9: `intuition/intuition.h`, `intuition/gadgetclass.h`, `libraries/gadtools.h`
|
||||
- ADCD 2.1: `CreateGadget()`, `GT_SetGadgetAttrs()`, `GT_GetGadgetAttrs()`
|
||||
- AmigaOS Reference Manual (RKRM): Libraries, Chapter 7 — Gadgets
|
||||
- See also: [BOOPSI](boopsi.md), [IDCMP](idcmp.md), [Windows](windows.md)
|
||||
|
|
|
|||
File diff suppressed because it is too large
Load diff
|
|
@ -1,115 +1,850 @@
|
|||
[← Home](../README.md) · [Intuition](README.md)
|
||||
|
||||
# Input Events — InputEvent, input.device, Commodities
|
||||
# Input Events
|
||||
|
||||
## Overview
|
||||
## What Are Input Events?
|
||||
|
||||
All user input (keyboard, mouse, joystick) flows through `input.device` as `InputEvent` structures. Commodities Exchange provides a high-level API for hotkeys and input filtering.
|
||||
Input events are the lowest-level representation of user activity in AmigaOS. Before Intuition sees a mouse click or key press, before [IDCMP](idcmp.md) delivers an `IntuiMessage` — there is the **input event pipeline**. Understanding this layer is essential for:
|
||||
|
||||
- Writing input handlers (hotkey daemons, key remappers, accessibility tools)
|
||||
- Building Commodities (Exchange-compatible background utilities)
|
||||
- Implementing game input that bypasses Intuition's overhead
|
||||
- Debugging input routing issues
|
||||
|
||||
---
|
||||
|
||||
## Architecture
|
||||
|
||||
```mermaid
|
||||
graph TB
|
||||
HW["Hardware Interrupts<br/>(keyboard, mouse, gameport)"] --> ID["input.device<br/>Creates InputEvent chain"]
|
||||
ID --> CHAIN["Input Handler Chain<br/>(prioritized list)"]
|
||||
CHAIN --> H100["Priority 100+<br/>Raw access"]
|
||||
H100 --> CX["Commodities Exchange<br/>(priority 51)"]
|
||||
CX --> INT["Intuition<br/>(priority 50)"]
|
||||
INT --> CON["console.device<br/>(priority 0)"]
|
||||
CON --> SINK["System Sink<br/>(priority -128)"]
|
||||
|
||||
style HW fill:#f5f5f5,stroke:#bdbdbd,color:#333
|
||||
style INT fill:#e8f4fd,stroke:#2196f3,color:#333
|
||||
style CX fill:#e8f5e9,stroke:#4caf50,color:#333
|
||||
```
|
||||
|
||||
### The Handler Chain
|
||||
|
||||
Input handlers are registered at specific priorities. Each handler receives the full event chain and can:
|
||||
|
||||
| Action | Effect |
|
||||
|---|---|
|
||||
| **Pass through** | Return events unmodified — next handler sees them |
|
||||
| **Consume** | Set `ie_Class = IECLASS_NULL` — event is swallowed |
|
||||
| **Modify** | Change event fields (remap keys, adjust coordinates) |
|
||||
| **Inject** | Add new synthetic events to the chain |
|
||||
|
||||
### Priority Conventions
|
||||
|
||||
| Priority | Owner | Purpose |
|
||||
|---|---|---|
|
||||
| 100+ | Custom raw handlers | Hardware monitoring, accessibility |
|
||||
| 51 | Commodities Exchange | Hotkeys, screen blankers, popup tools |
|
||||
| 50 | Intuition | GUI event processing (screens, windows, gadgets) |
|
||||
| 20–49 | Application handlers | Game input, custom input processing |
|
||||
| 0 | console.device | Terminal/shell input translation |
|
||||
| -128 | System sink | Catches anything nobody else wanted |
|
||||
|
||||
### Event Class Routing and QoS
|
||||
|
||||
The handler chain is the Amiga's equivalent of a **Quality-of-Service** pipeline. Priority determines who sees events first, but event *class* determines what happens at each stage:
|
||||
|
||||
```mermaid
|
||||
graph TB
|
||||
subgraph "Event Generation"
|
||||
KB["keyboard.device<br/>IECLASS_RAWKEY"]
|
||||
MS["gameport.device<br/>IECLASS_RAWMOUSE"]
|
||||
TM["timer.device<br/>IECLASS_TIMER"]
|
||||
GP["gameport.device<br/>(joystick mode)<br/>IECLASS_RAWMOUSE"]
|
||||
end
|
||||
|
||||
subgraph "Handler Chain (Priority Order)"
|
||||
H100["Custom (100+)<br/>Sees ALL events"]
|
||||
CX51["Commodities (51)<br/>Filters hotkeys"]
|
||||
INT50["Intuition (50)<br/>Consumes GUI events"]
|
||||
CON0["console.device (0)<br/>Translates keys → text"]
|
||||
end
|
||||
|
||||
KB --> H100
|
||||
MS --> H100
|
||||
TM --> H100
|
||||
GP --> H100
|
||||
H100 --> CX51
|
||||
CX51 --> INT50
|
||||
INT50 --> CON0
|
||||
|
||||
style INT50 fill:#e8f4fd,stroke:#2196f3,color:#333
|
||||
style CX51 fill:#e8f5e9,stroke:#4caf50,color:#333
|
||||
```
|
||||
|
||||
#### What Intuition Consumes vs Passes
|
||||
|
||||
This is critical: Intuition does **not** consume all events. It acts as a selective filter:
|
||||
|
||||
| Event Class | Intuition's Action | Survives to console.device? |
|
||||
|---|---|---|
|
||||
| `IECLASS_RAWKEY` | Checks for screen/window shortcuts (Left-Amiga combos). Passes others through as IDCMP + to console | **Yes** (unless consumed by Amiga shortcut) |
|
||||
| `IECLASS_RAWMOUSE` | Hit-tests gadgets, menus, screen drag. Consumes clicks on UI elements | **Partially** — movement passes, clicks on gadgets consumed |
|
||||
| `IECLASS_TIMER` | Uses for INTUITICKS (~10 Hz), key repeat | **Yes** |
|
||||
| `IECLASS_DISKINSERTED/REMOVED` | Passes to active window via IDCMP | **Yes** |
|
||||
| `IECLASS_NEWPOINTERPOS` | Updates pointer position | **Consumed** |
|
||||
|
||||
#### Priority as QoS: Who Gets First Refusal
|
||||
|
||||
The priority system creates an implicit QoS hierarchy:
|
||||
|
||||
| QoS Tier | Priority Range | Guarantee | Trade-off |
|
||||
|---|---|---|---|
|
||||
| **Real-time** | 100+ | First access to raw events; can block everything below | Must be extremely fast — delays entire system |
|
||||
| **System services** | 51–99 | Sees events before Intuition; can intercept and remap | Runs for every single event, even irrelevant ones |
|
||||
| **Intuition** | 50 | Full GUI routing — menus, gadgets, window management | Fixed; cannot be moved |
|
||||
| **Application** | 1–49 | Only sees events Intuition didn't consume | Misses GUI clicks but gets everything else |
|
||||
| **Console** | 0 | Terminal text translation | Only gets keyboard events that survived |
|
||||
| **Sink** | Negative | Last resort — error logging, debugging | Gets whatever nobody wanted |
|
||||
|
||||
#### Key Insight: No Selective Subscription
|
||||
|
||||
Unlike [IDCMP](idcmp.md) where you subscribe to specific event classes, **input handlers receive ALL events regardless of class**. The handler must filter by `ie_Class` internally:
|
||||
|
||||
```c
|
||||
/* Handler receives EVERYTHING — filter for what you care about */
|
||||
for (ev = events; ev; ev = ev->ie_NextEvent)
|
||||
{
|
||||
switch (ev->ie_Class)
|
||||
{
|
||||
case IECLASS_RAWKEY:
|
||||
/* Handle keyboard */
|
||||
break;
|
||||
/* Ignore RAWMOUSE, TIMER, etc. — just pass through */
|
||||
}
|
||||
}
|
||||
```
|
||||
|
||||
This means a handler at priority 100 that does expensive processing on every event will delay **all** mouse movement, **all** key presses, and **all** timer events for the entire system. This is why handler performance is critical — there is no OS-level event filtering.
|
||||
|
||||
#### lowlevel.library — Bypassing the Chain
|
||||
|
||||
For CD32 and game-oriented applications, `lowlevel.library` provides interrupt-driven input that sidesteps the handler chain entirely:
|
||||
|
||||
```c
|
||||
#include <libraries/lowlevel.h>
|
||||
#include <proto/lowlevel.h>
|
||||
|
||||
struct Library *LowLevelBase = OpenLibrary("lowlevel.library", 40);
|
||||
|
||||
/* Read joystick — bypasses input.device entirely */
|
||||
ULONG portState = ReadJoyPort(1); /* Port 1 */
|
||||
|
||||
if (portState & JPF_BUTTON_RED) /* Fire button */
|
||||
if (portState & JP_DIRECTION_MASK) /* Directional input */
|
||||
{
|
||||
if (portState & JPF_JOY_UP) /* Up */
|
||||
if (portState & JPF_JOY_DOWN) /* Down */
|
||||
if (portState & JPF_JOY_LEFT) /* Left */
|
||||
if (portState & JPF_JOY_RIGHT) /* Right */
|
||||
}
|
||||
|
||||
/* Keyboard interrupt — not in handler chain */
|
||||
APTR kbInt = AddKBInt(MyKeyHandler, myData);
|
||||
/* ... */
|
||||
RemKBInt(kbInt);
|
||||
|
||||
CloseLibrary(LowLevelBase);
|
||||
```
|
||||
|
||||
**Trade-off**: `lowlevel.library` is fast and simple but completely bypasses the OS input infrastructure. Intuition never sees these events, so GUI applications cannot use it. It's strictly for games and demos that own the display.
|
||||
|
||||
---
|
||||
|
||||
## struct InputEvent
|
||||
|
||||
```c
|
||||
/* devices/inputevent.h — NDK39 */
|
||||
/* devices/inputevent.h — NDK 3.9 */
|
||||
struct InputEvent {
|
||||
struct InputEvent *ie_NextEvent;
|
||||
UBYTE ie_Class; /* IECLASS_* */
|
||||
UBYTE ie_SubClass;
|
||||
UWORD ie_Code; /* keycode or button code */
|
||||
UWORD ie_Qualifier; /* IEQUALIFIER_* flags */
|
||||
struct InputEvent *ie_NextEvent; /* Linked list — events arrive in chains */
|
||||
UBYTE ie_Class; /* IECLASS_* — event type */
|
||||
UBYTE ie_SubClass; /* Subclass (usually 0) */
|
||||
UWORD ie_Code; /* Key scancode or button code */
|
||||
UWORD ie_Qualifier; /* IEQUALIFIER_* modifier bitmask */
|
||||
union {
|
||||
struct { WORD ie_x, ie_y; } ie_xy;
|
||||
APTR ie_addr;
|
||||
struct { UBYTE ie_prev1DownCode, ie_prev1DownQual;
|
||||
UBYTE ie_prev2DownCode, ie_prev2DownQual; } ie_dead;
|
||||
struct {
|
||||
WORD ie_x; /* Mouse X (absolute or relative) */
|
||||
WORD ie_y; /* Mouse Y (absolute or relative) */
|
||||
} ie_xy;
|
||||
APTR ie_addr; /* Dead key data or other pointer */
|
||||
struct {
|
||||
UBYTE ie_prev1DownCode; /* Previous key 1 (for dead keys) */
|
||||
UBYTE ie_prev1DownQual;
|
||||
UBYTE ie_prev2DownCode; /* Previous key 2 */
|
||||
UBYTE ie_prev2DownQual;
|
||||
} ie_dead;
|
||||
} ie_position;
|
||||
struct timeval ie_TimeStamp;
|
||||
struct timeval ie_TimeStamp; /* When the event occurred */
|
||||
};
|
||||
```
|
||||
|
||||
### Field Reference
|
||||
|
||||
| Field | Type | Description |
|
||||
|---|---|---|
|
||||
| `ie_NextEvent` | `InputEvent *` | Next event in chain — handlers process linked lists |
|
||||
| `ie_Class` | `UBYTE` | Event type (see table below) |
|
||||
| `ie_SubClass` | `UBYTE` | Typically 0; for `IECLASS_NEWPOINTERPOS` indicates format |
|
||||
| `ie_Code` | `UWORD` | **Keyboard**: scancode (0x00–0x7F = down, 0x80+ = up). **Mouse**: `IECODE_LBUTTON`, `IECODE_RBUTTON`, `IECODE_MBUTTON` + `IECODE_UP_PREFIX` for release |
|
||||
| `ie_Qualifier` | `UWORD` | Same `IEQUALIFIER_*` flags as in [IDCMP IntuiMessage](idcmp.md#qualifier-flags) |
|
||||
| `ie_xy.ie_x/y` | `WORD` | Mouse position or delta |
|
||||
| `ie_addr` | `APTR` | Dead-key translation data (for key events) |
|
||||
| `ie_TimeStamp` | `struct timeval` | Seconds and microseconds since boot |
|
||||
|
||||
---
|
||||
|
||||
## Event Classes
|
||||
|
||||
| Class | Constant | Description |
|
||||
| Class | Value | Source | Description |
|
||||
|---|---|---|---|
|
||||
| `IECLASS_NULL` | `0x00` | System | No-op — consumed/swallowed event |
|
||||
| `IECLASS_RAWKEY` | `0x01` | Keyboard | Key press/release (raw scancode) |
|
||||
| `IECLASS_RAWMOUSE` | `0x02` | Mouse | Button press/release and movement |
|
||||
| `IECLASS_EVENT` | `0x03` | Intuition | Cooked event (post-Intuition processing) |
|
||||
| `IECLASS_POINTERPOS` | `0x04` | System | Absolute pointer position update |
|
||||
| `IECLASS_TIMER` | `0x06` | Timer | Periodic timer event (for input polling) |
|
||||
| `IECLASS_GADGETDOWN` | `0x07` | Intuition | Gadget pressed |
|
||||
| `IECLASS_GADGETUP` | `0x08` | Intuition | Gadget released |
|
||||
| `IECLASS_REQUESTER` | `0x09` | Intuition | Requester activated |
|
||||
| `IECLASS_MENULIST` | `0x0A` | Intuition | Menu list activated |
|
||||
| `IECLASS_CLOSEWINDOW` | `0x0B` | Intuition | Close gadget clicked |
|
||||
| `IECLASS_SIZEWINDOW` | `0x0C` | Intuition | Window resized |
|
||||
| `IECLASS_REFRESHWINDOW` | `0x0D` | Intuition | Window refresh needed |
|
||||
| `IECLASS_NEWPREFS` | `0x0E` | System | Preferences changed |
|
||||
| `IECLASS_DISKREMOVED` | `0x0F` | System | Disk removed |
|
||||
| `IECLASS_DISKINSERTED` | `0x10` | System | Disk inserted |
|
||||
| `IECLASS_ACTIVEWINDOW` | `0x11` | Intuition | Window activated |
|
||||
| `IECLASS_INACTIVEWINDOW` | `0x12` | Intuition | Window deactivated |
|
||||
| `IECLASS_NEWPOINTERPOS` | `0x13` | System | New pointer position (extended format) |
|
||||
| `IECLASS_MENUHELP` | `0x14` | Intuition | Help key pressed on menu item |
|
||||
| `IECLASS_CHANGEWINDOW` | `0x15` | Intuition | Window moved/resized |
|
||||
|
||||
### Key Codes (RAWKEY)
|
||||
|
||||
| Scancode | Key | Scancode | Key |
|
||||
|---|---|---|---|
|
||||
| `0x00–0x31` | Alphanumeric (row by row) | `0x40` | Space |
|
||||
| `0x41` | Backspace | `0x42` | Tab |
|
||||
| `0x43` | Enter (keypad) | `0x44` | Return |
|
||||
| `0x45` | Escape | `0x46` | Delete |
|
||||
| `0x4C` | Cursor Up | `0x4D` | Cursor Down |
|
||||
| `0x4E` | Cursor Right | `0x4F` | Cursor Left |
|
||||
| `0x50–0x59` | F1–F10 | `0x60` | Left Shift |
|
||||
| `0x61` | Right Shift | `0x62` | Caps Lock |
|
||||
| `0x63` | Control | `0x64` | Left Alt |
|
||||
| `0x65` | Right Alt | `0x66` | Left Amiga |
|
||||
| `0x67` | Right Amiga | `0x68–0x77` | (Reserved) |
|
||||
|
||||
Key-up events have bit 7 set: scancode `0x45` (ESC down), `0xC5` (ESC up).
|
||||
|
||||
### Mouse Codes
|
||||
|
||||
| Code | Constant | Description |
|
||||
|---|---|---|
|
||||
| `IECLASS_RAWKEY` | `$01` | Raw keyboard event |
|
||||
| `IECLASS_RAWMOUSE` | `$02` | Raw mouse button/movement |
|
||||
| `IECLASS_EVENT` | `$03` | Cooked event from Intuition |
|
||||
| `IECLASS_POINTERPOS` | `$04` | Absolute pointer position |
|
||||
| `IECLASS_TIMER` | `$06` | Timer event |
|
||||
| `IECLASS_GADGETDOWN` | `$07` | Gadget pressed |
|
||||
| `IECLASS_GADGETUP` | `$08` | Gadget released |
|
||||
| `IECLASS_DISKINSERTED` | `$09` | Disk inserted |
|
||||
| `IECLASS_DISKREMOVED` | `$0A` | Disk removed |
|
||||
| `IECLASS_NEWPREFS` | `$0C` | Preferences changed |
|
||||
| `0x68` | `IECODE_LBUTTON` | Left button down |
|
||||
| `0xE8` | `IECODE_LBUTTON \| IECODE_UP_PREFIX` | Left button up |
|
||||
| `0x69` | `IECODE_RBUTTON` | Right button down |
|
||||
| `0xE9` | `IECODE_RBUTTON \| IECODE_UP_PREFIX` | Right button up |
|
||||
| `0x6A` | `IECODE_MBUTTON` | Middle button down |
|
||||
| `0xEA` | `IECODE_MBUTTON \| IECODE_UP_PREFIX` | Middle button up |
|
||||
|
||||
---
|
||||
|
||||
## Installing an Input Handler
|
||||
|
||||
### Registration
|
||||
|
||||
```c
|
||||
#include <devices/input.h>
|
||||
|
||||
/* Open input.device */
|
||||
struct MsgPort *inputPort = CreateMsgPort();
|
||||
struct IOStdReq *inputReq = (struct IOStdReq *)
|
||||
CreateIORequest(inputPort, sizeof(struct IOStdReq));
|
||||
OpenDevice("input.device", 0, (struct IORequest *)inputReq, 0);
|
||||
|
||||
/* Create handler */
|
||||
struct Interrupt handler;
|
||||
handler.is_Code = (APTR)MyInputHandler;
|
||||
handler.is_Data = myPrivateData;
|
||||
handler.is_Node.ln_Pri = 51; /* Above Intuition */
|
||||
handler.is_Node.ln_Name = "MyHandler";
|
||||
handler.is_Node.ln_Type = NT_INTERRUPT;
|
||||
|
||||
/* Install */
|
||||
inputReq->io_Command = IND_ADDHANDLER;
|
||||
inputReq->io_Data = &handler;
|
||||
DoIO((struct IORequest *)inputReq);
|
||||
```
|
||||
|
||||
### The Handler Function
|
||||
|
||||
Input handlers run in the **input.device task context** — not your application's context. They must follow strict rules:
|
||||
|
||||
```c
|
||||
struct InputEvent * __saveds MyInputHandler(
|
||||
struct InputEvent *events __asm("a0"),
|
||||
APTR data __asm("a1"))
|
||||
{
|
||||
struct InputEvent *ev;
|
||||
|
||||
for (ev = events; ev; ev = ev->ie_NextEvent)
|
||||
{
|
||||
/* Example: Remap Caps Lock to Control */
|
||||
if (ev->ie_Class == IECLASS_RAWKEY)
|
||||
{
|
||||
UWORD code = ev->ie_Code & ~IECODE_UP_PREFIX;
|
||||
if (code == 0x62) /* Caps Lock scancode */
|
||||
{
|
||||
ev->ie_Code = (ev->ie_Code & IECODE_UP_PREFIX) | 0x63; /* Control */
|
||||
}
|
||||
}
|
||||
|
||||
/* Example: Swallow middle mouse button */
|
||||
if (ev->ie_Class == IECLASS_RAWMOUSE &&
|
||||
(ev->ie_Code & ~IECODE_UP_PREFIX) == IECODE_MBUTTON)
|
||||
{
|
||||
ev->ie_Class = IECLASS_NULL; /* Consume the event */
|
||||
}
|
||||
}
|
||||
|
||||
return events; /* Always return the chain! */
|
||||
}
|
||||
```
|
||||
|
||||
### Handler Rules
|
||||
|
||||
| Rule | Reason | Correct Approach |
|
||||
|---|---|---|
|
||||
| **Never call Intuition functions** | You're in the input task — Intuition may `Wait()` internally → deadlock | `Signal()` your main task; call Intuition there |
|
||||
| **Never call DOS functions** | DOS is not reentrant from this context | `Signal()` your main task; call DOS there |
|
||||
| **Never allocate memory** | `AllocMem()` may need to `Wait()` — forbidden in handler | Pre-allocate all buffers before installing the handler |
|
||||
| **Always return the event chain** | Returning NULL kills **all input** for all applications | Return `events` even if you consumed some (set them to `IECLASS_NULL`) |
|
||||
| **Keep it fast** | You're blocking all input for the entire system | Filter by `ie_Class` early; skip irrelevant events immediately |
|
||||
| **Use `Signal()` for communication** | Only safe IPC from handler context | Set a flag + Signal; process in your event loop |
|
||||
|
||||
#### The Signal Pattern (Proper Handler → Application Communication)
|
||||
|
||||
```c
|
||||
/* --- Data shared between handler and main task --- */
|
||||
struct HandlerData {
|
||||
struct Task *mainTask; /* Pre-resolved with FindTask(NULL) */
|
||||
ULONG signalMask; /* Pre-allocated with AllocSignal() */
|
||||
volatile BOOL escapePressed; /* Flag set by handler */
|
||||
volatile UWORD lastRawKey; /* Last keycode seen */
|
||||
};
|
||||
|
||||
/* --- Handler (runs in input.device context) --- */
|
||||
struct InputEvent * __saveds MyHandler(
|
||||
struct InputEvent *events __asm("a0"),
|
||||
APTR data __asm("a1"))
|
||||
{
|
||||
struct HandlerData *hd = (struct HandlerData *)data;
|
||||
struct InputEvent *ev;
|
||||
|
||||
for (ev = events; ev; ev = ev->ie_NextEvent)
|
||||
{
|
||||
if (ev->ie_Class == IECLASS_RAWKEY &&
|
||||
!(ev->ie_Code & IECODE_UP_PREFIX)) /* Key down only */
|
||||
{
|
||||
hd->lastRawKey = ev->ie_Code;
|
||||
|
||||
if (ev->ie_Code == 0x45) /* Escape */
|
||||
hd->escapePressed = TRUE;
|
||||
|
||||
/* Wake main task — it will read the flags */
|
||||
Signal(hd->mainTask, hd->signalMask);
|
||||
}
|
||||
}
|
||||
|
||||
return events; /* ALWAYS return the chain */
|
||||
}
|
||||
|
||||
/* --- Main task setup --- */
|
||||
struct HandlerData hd;
|
||||
hd.mainTask = FindTask(NULL);
|
||||
BYTE sigBit = AllocSignal(-1);
|
||||
hd.signalMask = 1L << sigBit;
|
||||
hd.escapePressed = FALSE;
|
||||
hd.lastRawKey = 0;
|
||||
|
||||
/* Install handler ... (as shown above) */
|
||||
|
||||
/* --- Main task event loop --- */
|
||||
ULONG handlerSig = hd.signalMask;
|
||||
ULONG idcmpSig = 1L << win->UserPort->mp_SigBit;
|
||||
|
||||
while (running)
|
||||
{
|
||||
ULONG received = Wait(handlerSig | idcmpSig | SIGBREAKF_CTRL_C);
|
||||
|
||||
if (received & handlerSig)
|
||||
{
|
||||
/* NOW safe to call Intuition, DOS, anything */
|
||||
if (hd.escapePressed)
|
||||
{
|
||||
hd.escapePressed = FALSE;
|
||||
DisplayBeep(NULL); /* Intuition call — safe here! */
|
||||
running = FALSE;
|
||||
}
|
||||
}
|
||||
|
||||
if (received & idcmpSig)
|
||||
{
|
||||
/* Handle normal IDCMP messages */
|
||||
}
|
||||
}
|
||||
|
||||
/* Cleanup: remove handler, then free signal */
|
||||
/* ... IND_REMHANDLER ... */
|
||||
FreeSignal(sigBit);
|
||||
```
|
||||
|
||||
### Removal
|
||||
|
||||
```c
|
||||
inputReq->io_Command = IND_REMHANDLER;
|
||||
inputReq->io_Data = &handler;
|
||||
DoIO((struct IORequest *)inputReq);
|
||||
|
||||
CloseDevice((struct IORequest *)inputReq);
|
||||
DeleteIORequest(inputReq);
|
||||
DeleteMsgPort(inputPort);
|
||||
```
|
||||
|
||||
---
|
||||
|
||||
## Commodities Exchange
|
||||
|
||||
The **Commodities** system (OS 2.0+) provides a high-level, safe alternative to raw input handlers. Commodities are background utilities that can filter, respond to, and generate input events without the dangers of direct handler installation.
|
||||
|
||||
### Architecture
|
||||
|
||||
```mermaid
|
||||
graph LR
|
||||
INPUT["input.device"] --> CX["Commodities<br/>Exchange<br/>(priority 51)"]
|
||||
CX --> BROKER1["Your Broker"]
|
||||
CX --> BROKER2["ClickToFront"]
|
||||
CX --> BROKER3["ScreenBlanker"]
|
||||
BROKER1 --> FILTER["CxFilter<br/>'ctrl alt d'"]
|
||||
FILTER --> SENDER["CxSender<br/>→ your MsgPort"]
|
||||
BROKER1 --> XLATE["CxTranslate<br/>(key remap)"]
|
||||
|
||||
style CX fill:#e8f5e9,stroke:#4caf50,color:#333
|
||||
style BROKER1 fill:#fff3e0,stroke:#ff9800,color:#333
|
||||
```
|
||||
|
||||
### Creating a Commodity
|
||||
|
||||
```c
|
||||
#include <libraries/commodities.h>
|
||||
#include <proto/commodities.h>
|
||||
|
||||
struct Library *CxBase = OpenLibrary("commodities.library", 37);
|
||||
struct MsgPort *cxPort = CreateMsgPort();
|
||||
|
||||
/* Broker description */
|
||||
struct NewBroker nb = {
|
||||
NB_VERSION,
|
||||
"MyTool", /* Name (shown in Exchange) */
|
||||
"My Utility Tool v1.0", /* Title */
|
||||
"Hotkey utility for ...", /* Description */
|
||||
NBU_UNIQUE | NBU_NOTIFY, /* Only one instance */
|
||||
0, /* Flags */
|
||||
0, /* Priority */
|
||||
cxPort, /* Message port */
|
||||
0 /* Reserved */
|
||||
};
|
||||
|
||||
/* Create a hotkey filter: */
|
||||
CxObj *broker = CxBroker(&nb, NULL);
|
||||
CxObj *filter = CxFilter("ctrl alt d"); /* hotkey string */
|
||||
CxObj *sender = CxSender(port, CX_HOTKEY_ID); /* send msg to port */
|
||||
AttachCxObj(filter, sender);
|
||||
AttachCxObj(broker, filter);
|
||||
ActivateCxObj(broker, TRUE);
|
||||
```
|
||||
|
||||
/* In event loop: */
|
||||
CxMsg *msg;
|
||||
while ((msg = (CxMsg *)GetMsg(port))) {
|
||||
ULONG type = CxMsgType(msg);
|
||||
ULONG id = CxMsgID(msg);
|
||||
ReplyMsg((struct Message *)msg);
|
||||
if (type == CXM_COMMAND && id == CXCMD_KILL) running = FALSE;
|
||||
if (type == CXM_IEVENT && id == CX_HOTKEY_ID) /* hotkey pressed */;
|
||||
### Hotkey Detection
|
||||
|
||||
```c
|
||||
/* Create a hotkey filter */
|
||||
CxObj *filter = CxFilter("ctrl alt d");
|
||||
if (filter)
|
||||
{
|
||||
CxObj *sender = CxSender(cxPort, EVT_HOTKEY);
|
||||
if (sender)
|
||||
{
|
||||
AttachCxObj(filter, sender);
|
||||
}
|
||||
AttachCxObj(broker, filter);
|
||||
}
|
||||
|
||||
/* Activate the broker */
|
||||
ActivateCxObj(broker, TRUE);
|
||||
```
|
||||
|
||||
### Hotkey String Syntax
|
||||
|
||||
| Syntax | Description | Example |
|
||||
|---|---|---|
|
||||
| `"ctrl alt d"` | Modifier + key | Ctrl+Alt+D |
|
||||
| `"rawkey lshift rshift escape"` | Raw key with modifiers | Both Shifts + Esc |
|
||||
| `"rawkey f1"` | Function key | F1 |
|
||||
| `"-upstroke rawkey capslock"` | Key release event | Caps Lock released |
|
||||
| `"alt -repeat a"` | Alt+A, suppress auto-repeat | Single trigger |
|
||||
|
||||
### Event Loop
|
||||
|
||||
```c
|
||||
ULONG cxSig = 1L << cxPort->mp_SigBit;
|
||||
BOOL running = TRUE;
|
||||
|
||||
while (running)
|
||||
{
|
||||
ULONG received = Wait(cxSig | SIGBREAKF_CTRL_C);
|
||||
|
||||
if (received & SIGBREAKF_CTRL_C) running = FALSE;
|
||||
|
||||
if (received & cxSig)
|
||||
{
|
||||
CxMsg *msg;
|
||||
while ((msg = (CxMsg *)GetMsg(cxPort)))
|
||||
{
|
||||
ULONG type = CxMsgType(msg);
|
||||
ULONG id = CxMsgID(msg);
|
||||
ReplyMsg((struct Message *)msg);
|
||||
|
||||
switch (type)
|
||||
{
|
||||
case CXM_IEVENT:
|
||||
if (id == EVT_HOTKEY)
|
||||
{
|
||||
/* Hotkey was pressed — open window, etc. */
|
||||
HandleHotkey();
|
||||
}
|
||||
break;
|
||||
|
||||
case CXM_COMMAND:
|
||||
switch (id)
|
||||
{
|
||||
case CXCMD_DISABLE:
|
||||
ActivateCxObj(broker, FALSE);
|
||||
break;
|
||||
case CXCMD_ENABLE:
|
||||
ActivateCxObj(broker, TRUE);
|
||||
break;
|
||||
case CXCMD_KILL:
|
||||
running = FALSE;
|
||||
break;
|
||||
case CXCMD_UNIQUE:
|
||||
/* Another instance tried to start — popup */
|
||||
HandlePopup();
|
||||
break;
|
||||
}
|
||||
break;
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/* Cleanup */
|
||||
DeleteCxObjAll(broker);
|
||||
DeleteMsgPort(cxPort);
|
||||
CloseLibrary(CxBase);
|
||||
```
|
||||
|
||||
### Key Remapping with CxTranslate
|
||||
|
||||
```c
|
||||
/* Remap Caps Lock to Escape */
|
||||
CxObj *filter = CxFilter("rawkey capslock");
|
||||
InputEvent newEvent = { 0 };
|
||||
newEvent.ie_Class = IECLASS_RAWKEY;
|
||||
newEvent.ie_Code = 0x45; /* Escape scancode */
|
||||
CxObj *translate = CxTranslate(&newEvent);
|
||||
AttachCxObj(filter, translate);
|
||||
AttachCxObj(broker, filter);
|
||||
```
|
||||
|
||||
---
|
||||
|
||||
## Input Handler Installation
|
||||
## Injecting Synthetic Events
|
||||
|
||||
You can inject events as if they came from hardware:
|
||||
|
||||
```c
|
||||
/* Add a custom input handler (runs in input.device context): */
|
||||
struct Interrupt handler;
|
||||
handler.is_Code = (APTR)myInputHandler;
|
||||
handler.is_Data = myData;
|
||||
handler.is_Node.ln_Pri = 51; /* priority (above Intuition=50) */
|
||||
handler.is_Node.ln_Name = "MyHandler";
|
||||
/* Synthesize a key press */
|
||||
struct InputEvent ie = { 0 };
|
||||
ie.ie_Class = IECLASS_RAWKEY;
|
||||
ie.ie_Code = 0x23; /* 'D' key down */
|
||||
ie.ie_Qualifier = IEQUALIFIER_CONTROL; /* With Ctrl held */
|
||||
|
||||
struct IOStdReq *inputReq;
|
||||
/* ... open input.device ... */
|
||||
inputReq->io_Command = IND_ADDHANDLER;
|
||||
inputReq->io_Data = &handler;
|
||||
inputReq->io_Command = IND_WRITEEVENT;
|
||||
inputReq->io_Data = &ie;
|
||||
inputReq->io_Length = sizeof(struct InputEvent);
|
||||
DoIO((struct IORequest *)inputReq);
|
||||
```
|
||||
|
||||
/* Handler function: */
|
||||
struct InputEvent * __saveds myInputHandler(
|
||||
> **Warning**: Injected events go through the entire handler chain — including Intuition. They are indistinguishable from real input.
|
||||
|
||||
---
|
||||
|
||||
## Latency Analysis
|
||||
|
||||
### The Input Pipeline Timing Budget
|
||||
|
||||
Every input event travels through a chain of processing stages. On a stock 68000 at 7.09 MHz (PAL), the latency budget is tight:
|
||||
|
||||
```mermaid
|
||||
graph LR
|
||||
HW["Hardware IRQ<br/>~0 µs"] --> DRIVER["CIA/Gameport<br/>~20 µs"]
|
||||
DRIVER --> DEVICE["input.device<br/>~50 µs"]
|
||||
DEVICE --> HANDLERS["Handler Chain<br/>varies"]
|
||||
HANDLERS --> INT["Intuition<br/>~100–300 µs"]
|
||||
INT --> IDCMP["IDCMP delivery<br/>~50 µs"]
|
||||
IDCMP --> APP["App wakes<br/>from Wait()"]
|
||||
|
||||
style HANDLERS fill:#fff3e0,stroke:#ff9800,color:#333
|
||||
```
|
||||
|
||||
| Stage | Typical Latency (68000) | Typical Latency (68040) | Notes |
|
||||
|---|---|---|---|
|
||||
| Hardware interrupt | < 1 µs | < 1 µs | CIA or gameport triggers IRQ |
|
||||
| Device driver | ~20 µs | ~5 µs | Reads hardware registers, builds InputEvent |
|
||||
| input.device processing | ~50 µs | ~10 µs | Timestamps, links events into chain |
|
||||
| Handler chain (per handler) | 10–500 µs | 2–100 µs | **Your handler's budget** |
|
||||
| Intuition processing | 100–300 µs | 20–60 µs | Hit-testing, screen routing, layer locking |
|
||||
| IDCMP message allocation | ~50 µs | ~10 µs | AllocMem + PutMsg to UserPort |
|
||||
| Task switch to application | ~100 µs | ~20 µs | Exec scheduler latency |
|
||||
| **Total (IDCMP path)** | **~500–1000 µs** | **~70–200 µs** | One to two frames at 50 Hz |
|
||||
|
||||
### Key Insight: Frames vs Microseconds
|
||||
|
||||
At 50 Hz PAL (20 ms per frame), the total IDCMP path on a 68000 consumes **2.5–5% of a frame**. This is fine for GUI applications. For games targeting 50 fps with heavy rendering, this overhead matters.
|
||||
|
||||
### Input Strategy Comparison
|
||||
|
||||
| Strategy | Latency | CPU Cost | Complexity | Best For |
|
||||
|---|---|---|---|---|
|
||||
| **IDCMP** | ~1 ms (68000) | Zero when idle | Low | GUI applications, editors, utilities |
|
||||
| **Commodities filter** | ~0.5 ms | Zero when idle | Medium | Hotkey daemons, popup tools |
|
||||
| **Custom input handler** (pri > 50) | ~0.1 ms | Handler runs for every event | High | Key remappers, accessibility tools |
|
||||
| **Custom input handler** (pri < 50) | ~0.4 ms | Handler runs for every event | High | Post-Intuition filtering |
|
||||
| **Direct hardware read** | ~0 ms | Polled every frame | Low | Games, demos, real-time apps |
|
||||
| **gameport.device** | ~0.3 ms | Event-driven | Medium | Joystick/mouse in non-game apps |
|
||||
|
||||
---
|
||||
|
||||
## Game Input Patterns
|
||||
|
||||
For games and demos where latency matters, the IDCMP path is often too slow or too unpredictable. Several alternative patterns exist:
|
||||
|
||||
### Direct Hardware Polling
|
||||
|
||||
Read CIA and custom chip registers directly — zero latency, but requires careful synchronization:
|
||||
|
||||
```c
|
||||
/* Read joystick port 1 (JOY1DAT register) */
|
||||
#define JOY1DAT (*(volatile UWORD *)0xDFF00C)
|
||||
#define CIAAPRA (*(volatile UBYTE *)0xBFE001)
|
||||
|
||||
void ReadJoystick(BOOL *up, BOOL *down, BOOL *left, BOOL *right, BOOL *fire)
|
||||
{
|
||||
UWORD joy = JOY1DAT;
|
||||
|
||||
*right = (joy & 0x0002) ? TRUE : FALSE;
|
||||
*left = (joy & 0x0200) ? TRUE : FALSE;
|
||||
*down = ((joy >> 1) ^ joy) & 0x0001;
|
||||
*up = ((joy >> 1) ^ joy) & 0x0100;
|
||||
|
||||
/* Fire button is active-low on CIA-A PRA bit 7 (port 2) or bit 6 (port 1) */
|
||||
*fire = !(CIAAPRA & 0x0080); /* Port 1 fire */
|
||||
}
|
||||
```
|
||||
|
||||
### Keyboard via CIA
|
||||
|
||||
Read the keyboard register directly for games that need immediate key state:
|
||||
|
||||
```c
|
||||
#define CIAAICR (*(volatile UBYTE *)0xBFED01)
|
||||
#define CIAASDR (*(volatile UBYTE *)0xBFEC01)
|
||||
|
||||
/* Note: the keyboard sends inverted scancodes, MSB first */
|
||||
UBYTE ReadRawKey(void)
|
||||
{
|
||||
if (CIAAICR & 0x08) /* SP interrupt flag — key data ready */
|
||||
{
|
||||
UBYTE raw = ~CIAASDR; /* Invert */
|
||||
UBYTE code = (raw >> 1) | (raw << 7); /* Rotate right 1 bit */
|
||||
|
||||
/* Handshake: pulse SP line */
|
||||
CIAASDR = 0xFF; /* Drive SP high briefly */
|
||||
/* Brief delay */
|
||||
CIAASDR = 0x00; /* Release */
|
||||
|
||||
return code;
|
||||
}
|
||||
return 0xFF; /* No key */
|
||||
}
|
||||
```
|
||||
|
||||
> **Warning**: Direct hardware access bypasses the operating system entirely. If the OS is still running (not taken over), you'll conflict with `input.device`. Use this only in system-takeover scenarios.
|
||||
|
||||
### Cooperative Hybrid: Handler + Signal
|
||||
|
||||
The best approach for games that still want OS-friendly behavior:
|
||||
|
||||
```c
|
||||
/* Global state updated from input handler */
|
||||
volatile UWORD g_KeyState[8]; /* 128-bit key state bitmap */
|
||||
volatile WORD g_MouseDX, g_MouseDY;
|
||||
volatile UWORD g_MouseButtons;
|
||||
|
||||
struct InputEvent * __saveds GameInputHandler(
|
||||
struct InputEvent *events __asm("a0"),
|
||||
APTR data __asm("a1"))
|
||||
{
|
||||
struct InputEvent *ev;
|
||||
for (ev = events; ev; ev = ev->ie_NextEvent) {
|
||||
if (ev->ie_Class == IECLASS_RAWKEY && ev->ie_Code == 0x45) {
|
||||
ev->ie_Class = IECLASS_NULL; /* swallow ESC key */
|
||||
for (ev = events; ev; ev = ev->ie_NextEvent)
|
||||
{
|
||||
if (ev->ie_Class == IECLASS_RAWKEY)
|
||||
{
|
||||
UWORD code = ev->ie_Code & 0x7F;
|
||||
UWORD word = code >> 4;
|
||||
UWORD bit = 1 << (code & 0x0F);
|
||||
|
||||
if (ev->ie_Code & 0x80)
|
||||
g_KeyState[word] &= ~bit; /* Key up */
|
||||
else
|
||||
g_KeyState[word] |= bit; /* Key down */
|
||||
}
|
||||
else if (ev->ie_Class == IECLASS_RAWMOUSE)
|
||||
{
|
||||
g_MouseDX += ev->ie_position.ie_xy.ie_x;
|
||||
g_MouseDY += ev->ie_position.ie_xy.ie_y;
|
||||
g_MouseButtons = ev->ie_Code;
|
||||
}
|
||||
}
|
||||
return events; /* Pass through — Intuition still works */
|
||||
}
|
||||
|
||||
/* In game loop — read state directly, zero latency */
|
||||
BOOL IsKeyDown(UWORD scancode)
|
||||
{
|
||||
return (g_KeyState[scancode >> 4] & (1 << (scancode & 0x0F))) != 0;
|
||||
}
|
||||
```
|
||||
|
||||
This gives near-zero latency reads in the game loop while keeping the OS alive — Intuition, CLI, and Workbench all continue to function.
|
||||
|
||||
---
|
||||
|
||||
## Input Handler Performance Guidelines
|
||||
|
||||
### Keep Your Handler Under Budget
|
||||
|
||||
Every microsecond in your handler delays **all** input for **all** applications:
|
||||
|
||||
```c
|
||||
/* BAD — string comparison in handler (slow) */
|
||||
if (strcmp(someString, "pattern") == 0) { ... }
|
||||
|
||||
/* GOOD — numeric comparison (fast) */
|
||||
if (ev->ie_Code == 0x45 && (ev->ie_Qualifier & IEQUALIFIER_CONTROL)) { ... }
|
||||
```
|
||||
|
||||
### Signal Instead of Processing
|
||||
|
||||
```c
|
||||
/* BAD — complex processing in handler context */
|
||||
struct InputEvent * __saveds MyHandler(
|
||||
struct InputEvent *events __asm("a0"), APTR data __asm("a1"))
|
||||
{
|
||||
/* DON'T: open windows, update files, draw graphics */
|
||||
OpenWindow(...); /* DEADLOCK! */
|
||||
return events;
|
||||
}
|
||||
|
||||
/* GOOD — signal your task, process in main loop */
|
||||
struct InputEvent * __saveds MyHandler(
|
||||
struct InputEvent *events __asm("a0"), APTR data __asm("a1"))
|
||||
{
|
||||
struct MyData *md = (struct MyData *)data;
|
||||
struct InputEvent *ev;
|
||||
for (ev = events; ev; ev = ev->ie_NextEvent)
|
||||
{
|
||||
if (ev->ie_Class == IECLASS_RAWKEY && ev->ie_Code == 0x45)
|
||||
{
|
||||
md->escapePressed = TRUE;
|
||||
Signal(md->mainTask, md->signalMask); /* Wake main task */
|
||||
}
|
||||
}
|
||||
return events;
|
||||
}
|
||||
```
|
||||
|
||||
### Event Batching
|
||||
|
||||
Input events arrive in chains, not one at a time. A single handler invocation may process 1–20 events:
|
||||
|
||||
```c
|
||||
/* The input chain can look like:
|
||||
RAWKEY(down) → RAWMOUSE(move) → RAWMOUSE(move) → RAWKEY(up)
|
||||
|
||||
Process the entire chain in one pass — don't copy events! */
|
||||
```
|
||||
|
||||
---
|
||||
|
||||
## Pitfalls
|
||||
|
||||
### 1. Handler Never Returns Events
|
||||
|
||||
If your handler returns NULL instead of the event chain, **all input to the entire system stops**. The only recovery is a reboot.
|
||||
|
||||
### 2. Allocating Memory in Handler
|
||||
|
||||
`AllocMem()` may need to `Wait()` internally, which is forbidden in the input handler context. Pre-allocate everything.
|
||||
|
||||
### 3. Calling Intuition from Handler
|
||||
|
||||
Intuition functions require the calling task's context. Input handlers run in `input.device`'s task. Calling `OpenWindow()` from a handler causes an immediate deadlock.
|
||||
|
||||
### 4. Priority Conflicts
|
||||
|
||||
Two handlers at the same priority have undefined ordering. Always use distinct priorities.
|
||||
|
||||
### 5. Forgetting to Remove Handler
|
||||
|
||||
If your program exits without `IND_REMHANDLER`, the handler function pointer becomes a dangling reference. The next input event crashes the system.
|
||||
|
||||
---
|
||||
|
||||
## Best Practices
|
||||
|
||||
1. **Use Commodities** for hotkeys and simple input filtering — safer and simpler than raw handlers
|
||||
2. **Use IDCMP** for normal GUI input — it's designed for application-level events
|
||||
3. **Raw handlers only** when you need to intercept events before Intuition (key remapping, accessibility)
|
||||
4. **Always `Signal()` from handlers** — process events in your main task, not in the handler
|
||||
5. **Pre-allocate all memory** before installing a handler
|
||||
6. **Test with IND_REMHANDLER** — ensure clean removal in every exit path (including crashes)
|
||||
7. **Handle `CXCMD_KILL`** in Commodities — the Exchange program sends this to quit your commodity
|
||||
8. **Use `NBU_UNIQUE`** to prevent multiple instances of the same commodity
|
||||
|
||||
---
|
||||
|
||||
## References
|
||||
|
||||
- NDK39: `devices/inputevent.h`, `libraries/commodities.h`
|
||||
- ADCD 2.1: `CxBroker`, `CxFilter`, `CxSender`, input.device
|
||||
- NDK 3.9: `devices/inputevent.h`, `devices/input.h`, `libraries/commodities.h`
|
||||
- ADCD 2.1: `CxBroker()`, `CxFilter()`, `CxSender()`, `CxTranslate()`, `IND_ADDHANDLER`
|
||||
- AmigaOS Reference Manual (RKRM): Devices, Chapter 1 — Input Device
|
||||
- AmigaOS Reference Manual (RKRM): Libraries, Chapter 11 — Commodities Exchange
|
||||
- See also: [IDCMP](idcmp.md), [Screens](screens.md)
|
||||
|
|
|
|||
|
|
@ -2,37 +2,266 @@
|
|||
|
||||
# IntuitionBase — Global GUI State
|
||||
|
||||
## Overview
|
||||
## What Is IntuitionBase?
|
||||
|
||||
`intuition.library` manages screens, windows, menus, gadgets, and the input event pipeline. `IntuitionBase` is the library base containing active display state.
|
||||
`IntuitionBase` is the library base structure for `intuition.library` — the heart of the Amiga's graphical user interface. Unlike modern systems where the window manager is a separate process, Intuition is a **shared library** loaded into the system's address space. `IntuitionBase` contains the global state for all screens, windows, and input routing.
|
||||
|
||||
---
|
||||
|
||||
## struct IntuitionBase (Key Fields)
|
||||
|
||||
```c
|
||||
/* intuition/intuitionbase.h — NDK39 */
|
||||
struct IntuitionBase {
|
||||
struct Library LibNode;
|
||||
struct View ViewLord; /* master View */
|
||||
struct Window *ActiveWindow; /* currently active window */
|
||||
struct Screen *ActiveScreen; /* currently active screen */
|
||||
struct Screen *FirstScreen; /* head of screen list */
|
||||
/* ... private fields ... */
|
||||
};
|
||||
```
|
||||
|
||||
---
|
||||
|
||||
## Opening
|
||||
Every Amiga GUI program begins by opening this library:
|
||||
|
||||
```c
|
||||
struct IntuitionBase *IntuitionBase;
|
||||
IntuitionBase = (struct IntuitionBase *)OpenLibrary("intuition.library", 39);
|
||||
if (!IntuitionBase)
|
||||
{
|
||||
/* Running on a system older than OS 3.0 — exit gracefully */
|
||||
return RETURN_FAIL;
|
||||
}
|
||||
```
|
||||
|
||||
### Version Requirements
|
||||
|
||||
| Version | OS Release | Key Features Added |
|
||||
|---|---|---|
|
||||
| 33 | 1.2 | Original Intuition |
|
||||
| 36 | 2.0 | TagList APIs, public screens, BOOPSI, GadTools |
|
||||
| 37 | 2.04 | Improved memory handling |
|
||||
| 39 | 3.0 | New-look menus, enhanced DrawInfo, `ChangeWindowBox()` |
|
||||
| 40 | 3.1 | AppWindow/AppIcon improvements |
|
||||
| 47 | 3.2 | OS 3.2 additions (enhanced backfill, new screen tags) |
|
||||
| 50+ | 3.2.x | Continued 3.2 line improvements |
|
||||
|
||||
---
|
||||
|
||||
## struct IntuitionBase
|
||||
|
||||
```c
|
||||
/* intuition/intuitionbase.h — NDK 3.9 */
|
||||
struct IntuitionBase {
|
||||
struct Library LibNode; /* Standard library node */
|
||||
struct View ViewLord; /* Master graphics View */
|
||||
struct Window *ActiveWindow; /* Currently active window */
|
||||
struct Screen *ActiveScreen; /* Currently active screen */
|
||||
struct Screen *FirstScreen; /* Head of screen linked list */
|
||||
ULONG Flags; /* Internal state flags */
|
||||
WORD MouseY, MouseX; /* Current mouse position */
|
||||
ULONG Seconds, Micros; /* Current timestamp */
|
||||
/* ... many private/internal fields follow ... */
|
||||
};
|
||||
```
|
||||
|
||||
### Field Reference
|
||||
|
||||
| Field | Type | Description | Safe to Read? |
|
||||
|---|---|---|---|
|
||||
| `LibNode` | `struct Library` | Standard Exec library header — version, open count, etc. | Yes |
|
||||
| `ViewLord` | `struct View` | Master `View` structure — controls the entire display through the Copper | **No** — use graphics.library functions |
|
||||
| `ActiveWindow` | `struct Window *` | Pointer to the currently active window | Yes (with `Forbid()`/`Permit()`) |
|
||||
| `ActiveScreen` | `struct Screen *` | Pointer to the currently active screen | Yes (with `Forbid()`/`Permit()`) |
|
||||
| `FirstScreen` | `struct Screen *` | Head of the screen list (front-to-back order) | Yes (with `Forbid()`/`Permit()`) |
|
||||
| `Flags` | `ULONG` | Internal state flags | **No** — private |
|
||||
| `MouseY`, `MouseX` | `WORD` | Absolute mouse position on active screen | Yes |
|
||||
| `Seconds`, `Micros` | `ULONG` | System timestamp of last input event | Yes |
|
||||
|
||||
> **Warning**: Fields beyond those listed above are **private** and change between OS versions. Accessing undocumented fields will break your program on different OS releases.
|
||||
|
||||
---
|
||||
|
||||
## Using IntuitionBase
|
||||
|
||||
### Reading the Active Window
|
||||
|
||||
```c
|
||||
/* Must protect with Forbid/Permit — ActiveWindow can change asynchronously */
|
||||
Forbid();
|
||||
struct Window *active = IntuitionBase->ActiveWindow;
|
||||
if (active)
|
||||
{
|
||||
/* Read what you need while protected */
|
||||
STRPTR title = active->Title;
|
||||
/* ... */
|
||||
}
|
||||
Permit();
|
||||
```
|
||||
|
||||
### Walking the Screen List
|
||||
|
||||
```c
|
||||
Forbid();
|
||||
struct Screen *scr = IntuitionBase->FirstScreen;
|
||||
while (scr)
|
||||
{
|
||||
Printf("Screen: %s (%ldx%ld)\n",
|
||||
scr->Title ? scr->Title : "(no title)",
|
||||
scr->Width, scr->Height);
|
||||
scr = scr->NextScreen;
|
||||
}
|
||||
Permit();
|
||||
```
|
||||
|
||||
### Reading Mouse Position
|
||||
|
||||
```c
|
||||
/* Global mouse position (relative to active screen) */
|
||||
WORD mx = IntuitionBase->MouseX;
|
||||
WORD my = IntuitionBase->MouseY;
|
||||
|
||||
/* For window-relative position, use Window->MouseX/MouseY instead */
|
||||
```
|
||||
|
||||
---
|
||||
|
||||
## The ViewLord
|
||||
|
||||
`IntuitionBase->ViewLord` is the master `struct View` — the top-level graphics structure that controls the entire display. Intuition builds a Copper list from this View to render all screens.
|
||||
|
||||
```mermaid
|
||||
graph TB
|
||||
VL["ViewLord<br/>(struct View)"] --> VP1["ViewPort 1<br/>Workbench Screen"]
|
||||
VL --> VP2["ViewPort 2<br/>Custom Screen"]
|
||||
VL --> VP3["ViewPort 3<br/>Game Screen"]
|
||||
VP1 --> BM1["BitMap 1"]
|
||||
VP2 --> BM2["BitMap 2"]
|
||||
VP3 --> BM3["BitMap 3"]
|
||||
|
||||
style VL fill:#e8f4fd,stroke:#2196f3,color:#333
|
||||
```
|
||||
|
||||
You should **never** modify the ViewLord directly. Use `MakeScreen()`, `RethinkDisplay()`, or `RemakeDisplay()`:
|
||||
|
||||
```c
|
||||
/* After changing a screen's ViewPort (e.g., palette): */
|
||||
MakeScreen(scr); /* Rebuild this screen's Copper list */
|
||||
RethinkDisplay(); /* Rebuild the entire display from ViewLord */
|
||||
|
||||
/* Or the combined version: */
|
||||
RemakeDisplay(); /* MakeScreen + RethinkDisplay for all screens */
|
||||
```
|
||||
|
||||
---
|
||||
|
||||
## Library Functions Overview
|
||||
|
||||
### Screen Management
|
||||
|
||||
| Function | Description |
|
||||
|---|---|
|
||||
| `OpenScreenTagList()` | Open a new screen with tag-based configuration |
|
||||
| `CloseScreen()` | Close a screen (all windows must be closed first) |
|
||||
| `LockPubScreen()` | Lock a public screen by name (prevents closing) |
|
||||
| `UnlockPubScreen()` | Release a public screen lock |
|
||||
| `PubScreenStatus()` | Set public screen state (available / private) |
|
||||
| `GetScreenDrawInfo()` | Get pen and font information for a screen |
|
||||
| `FreeScreenDrawInfo()` | Release DrawInfo |
|
||||
| `ScreenToFront()` / `ScreenToBack()` | Change screen depth order |
|
||||
| `MoveScreen()` | Move screen vertically |
|
||||
|
||||
### Window Management
|
||||
|
||||
| Function | Description |
|
||||
|---|---|
|
||||
| `OpenWindowTagList()` | Open a new window with tag-based configuration |
|
||||
| `CloseWindow()` | Close a window |
|
||||
| `ActivateWindow()` | Make a window active |
|
||||
| `WindowToFront()` / `WindowToBack()` | Change window depth |
|
||||
| `MoveWindow()` / `SizeWindow()` | Adjust window position/size |
|
||||
| `ChangeWindowBox()` | Set absolute position and size |
|
||||
| `SetWindowTitles()` | Change window and screen titles |
|
||||
| `SetWindowPointer()` | Set custom or busy pointer |
|
||||
|
||||
### Gadget Management
|
||||
|
||||
| Function | Description |
|
||||
|---|---|
|
||||
| `AddGadget()` / `RemoveGadget()` | Add/remove gadgets from windows |
|
||||
| `RefreshGList()` | Redraw gadget(s) |
|
||||
| `SetGadgetAttrs()` | Set BOOPSI gadget attributes |
|
||||
| `ModifyIDCMP()` | Change IDCMP flags dynamically |
|
||||
|
||||
### Menu Management
|
||||
|
||||
| Function | Description |
|
||||
|---|---|
|
||||
| `SetMenuStrip()` | Attach menu strip to window |
|
||||
| `ClearMenuStrip()` | Remove menu strip from window |
|
||||
| `OnMenu()` / `OffMenu()` | Enable/disable menu items |
|
||||
| `ItemAddress()` | Get MenuItem pointer from packed menu number |
|
||||
|
||||
### Requesters and Dialogs
|
||||
|
||||
| Function | Description |
|
||||
|---|---|
|
||||
| `EasyRequest()` | Show a simple message dialog |
|
||||
| `BuildEasyRequest()` | Create a non-blocking requester |
|
||||
| `SysReqHandler()` | Poll a non-blocking requester |
|
||||
| `FreeSysRequest()` | Free a non-blocking requester |
|
||||
| `AutoRequest()` | Legacy two-button dialog (OS 1.x) |
|
||||
|
||||
### Rendering Support
|
||||
|
||||
| Function | Description |
|
||||
|---|---|
|
||||
| `DrawBorder()` | Draw a `struct Border` |
|
||||
| `PrintIText()` | Draw `struct IntuiText` |
|
||||
| `BeginRefresh()` / `EndRefresh()` | Simple-refresh window support |
|
||||
| `LockIBase()` / `UnlockIBase()` | Lock IntuitionBase for multi-field reads |
|
||||
|
||||
---
|
||||
|
||||
## LockIBase — Safe Multi-Field Access
|
||||
|
||||
When reading multiple IntuitionBase fields that must be consistent, use `LockIBase()`:
|
||||
|
||||
```c
|
||||
ULONG lock = LockIBase(0);
|
||||
|
||||
struct Window *active = IntuitionBase->ActiveWindow;
|
||||
struct Screen *screen = IntuitionBase->ActiveScreen;
|
||||
/* Both refer to the same moment in time */
|
||||
|
||||
UnlockIBase(lock);
|
||||
```
|
||||
|
||||
Without the lock, `ActiveWindow` could change between reading it and reading `ActiveScreen` — giving you a window on a different screen than expected.
|
||||
|
||||
> `LockIBase()` is heavier than `Forbid()`/`Permit()` — use it only when you need atomic multi-field reads. For single field access, `Forbid()`/`Permit()` is sufficient.
|
||||
|
||||
---
|
||||
|
||||
## Pitfalls
|
||||
|
||||
### 1. Not Checking Library Version
|
||||
|
||||
Opening `intuition.library` version 0 succeeds on any system, but tag-based functions (`OpenWindowTags`, `OpenScreenTags`) require version 36+. Always specify the minimum version you need.
|
||||
|
||||
### 2. Reading Private Fields
|
||||
|
||||
Many tools and examples from the late '80s directly access internal IntuitionBase fields (like internal semaphores or the gadget environment). These fields **moved between OS versions** — code that worked on 1.3 crashed on 2.0, and code that worked on 3.1 crashes on 3.2.
|
||||
|
||||
### 3. Writing to IntuitionBase
|
||||
|
||||
Never write to IntuitionBase fields directly. Use the provided API functions. Direct writes bypass Intuition's internal state management and cause corruption.
|
||||
|
||||
### 4. Forgetting Forbid/Permit
|
||||
|
||||
`ActiveWindow`, `ActiveScreen`, and `FirstScreen` can change at any time (multitasking). Reading without `Forbid()`/`Permit()` or `LockIBase()` creates a race condition.
|
||||
|
||||
---
|
||||
|
||||
## Best Practices
|
||||
|
||||
1. **Open with the minimum version you need** — e.g., `OpenLibrary("intuition.library", 39)` for OS 3.0 features
|
||||
2. **Use `LockIBase()`** for atomic multi-field reads from IntuitionBase
|
||||
3. **Use `Forbid()`/`Permit()`** for quick single-field reads
|
||||
4. **Never access undocumented fields** — they change between OS versions
|
||||
5. **Never modify IntuitionBase** — use API functions
|
||||
6. **Close the library** when done — `CloseLibrary((struct Library *)IntuitionBase)`
|
||||
7. **Check the library pointer** before using any functions — it may be NULL on pre-2.0 systems
|
||||
|
||||
---
|
||||
|
||||
## References
|
||||
|
||||
- NDK39: `intuition/intuitionbase.h`
|
||||
- NDK 3.9: `intuition/intuitionbase.h`, `intuition/intuition.h`
|
||||
- ADCD 2.1: `OpenLibrary()`, `LockIBase()`, `UnlockIBase()`
|
||||
- AmigaOS Reference Manual (RKRM): Libraries, Chapter 2 — Intuition Overview
|
||||
- See also: [Screens](screens.md), [Windows](windows.md), [IDCMP](idcmp.md)
|
||||
|
|
|
|||
|
|
@ -1,64 +1,378 @@
|
|||
[← Home](../README.md) · [Intuition](README.md)
|
||||
|
||||
# Menus — MenuStrip Construction
|
||||
# Menus
|
||||
|
||||
## Overview
|
||||
## What Are Menus?
|
||||
|
||||
Intuition menus are structured as: `Menu` → `MenuItem` → `SubItem`. Menus are attached to windows and appear when the user presses the right mouse button.
|
||||
Menus are Intuition's pull-down command system. When the user presses the **right mouse button**, Intuition displays a menu strip attached to the active window's screen title bar. Menus are the primary mechanism for accessing application commands that don't warrant dedicated gadgets.
|
||||
|
||||
The menu system has three levels:
|
||||
|
||||
```mermaid
|
||||
graph LR
|
||||
STRIP["Menu Strip"] --> M1["Menu: Project"]
|
||||
STRIP --> M2["Menu: Edit"]
|
||||
STRIP --> M3["Menu: Settings"]
|
||||
M1 --> I1["Item: New (Ctrl+N)"]
|
||||
M1 --> I2["Item: Open (Ctrl+O)"]
|
||||
M1 --> SEP["────────────"]
|
||||
M1 --> I3["Item: Quit (Ctrl+Q)"]
|
||||
M2 --> I4["Item: Cut (Ctrl+X)"]
|
||||
M2 --> I5["Item: Copy (Ctrl+C)"]
|
||||
M2 --> I6["Item: Paste (Ctrl+V)"]
|
||||
I6 --> S1["Sub: As Text"]
|
||||
I6 --> S2["Sub: As Image"]
|
||||
|
||||
style STRIP fill:#e8f4fd,stroke:#2196f3,color:#333
|
||||
```
|
||||
|
||||
| Level | Structure | Max Count | Description |
|
||||
|---|---|---|---|
|
||||
| **Menu** | `struct Menu` | 31 | Top-level categories (Project, Edit, etc.) |
|
||||
| **Item** | `struct MenuItem` | 63 | Commands within a menu |
|
||||
| **Sub-Item** | `struct MenuItem` | 31 | Nested commands within an item |
|
||||
|
||||
---
|
||||
|
||||
## GadTools Menu Creation (OS 2.0+)
|
||||
|
||||
The preferred way to create menus — handles layout, keyboard shortcuts, and the OS look-and-feel automatically:
|
||||
|
||||
### Defining the Menu Structure
|
||||
|
||||
```c
|
||||
struct NewMenu nm[] = {
|
||||
{ NM_TITLE, "Project", NULL, 0, 0, NULL },
|
||||
{ NM_ITEM, "New", "N", 0, 0, NULL },
|
||||
{ NM_ITEM, "Open...", "O", 0, 0, NULL },
|
||||
{ NM_ITEM, NM_BARLABEL, NULL, 0, 0, NULL }, /* separator */
|
||||
{ NM_ITEM, "Quit", "Q", 0, 0, NULL },
|
||||
{ NM_TITLE, "Edit", NULL, 0, 0, NULL },
|
||||
{ NM_ITEM, "Cut", "X", 0, 0, NULL },
|
||||
{ NM_ITEM, "Copy", "C", 0, 0, NULL },
|
||||
{ NM_ITEM, "Paste", "V", 0, 0, NULL },
|
||||
{ NM_END, NULL, NULL, 0, 0, NULL }
|
||||
#include <libraries/gadtools.h>
|
||||
#include <proto/gadtools.h>
|
||||
|
||||
/* Menu IDs — use an enum for clarity */
|
||||
enum {
|
||||
MENU_NEW = 1, MENU_OPEN, MENU_SAVE, MENU_SAVEAS, MENU_QUIT,
|
||||
MENU_CUT, MENU_COPY, MENU_PASTE, MENU_SELECTALL,
|
||||
MENU_BOLD, MENU_ITALIC, MENU_UNDERLINE
|
||||
};
|
||||
|
||||
struct Menu *menu = CreateMenus(nm, TAG_DONE);
|
||||
LayoutMenus(menu, vi, TAG_DONE);
|
||||
SetMenuStrip(win, menu);
|
||||
struct NewMenu nm[] = {
|
||||
{ NM_TITLE, "Project", NULL, 0, 0, NULL },
|
||||
{ NM_ITEM, "New", "N", 0, 0, (APTR)MENU_NEW },
|
||||
{ NM_ITEM, "Open...", "O", 0, 0, (APTR)MENU_OPEN },
|
||||
{ NM_ITEM, "Save", "S", 0, 0, (APTR)MENU_SAVE },
|
||||
{ NM_ITEM, "Save As...", "A", 0, 0, (APTR)MENU_SAVEAS },
|
||||
{ NM_ITEM, NM_BARLABEL, NULL, 0, 0, NULL }, /* Separator */
|
||||
{ NM_ITEM, "Quit", "Q", 0, 0, (APTR)MENU_QUIT },
|
||||
|
||||
/* In event loop on IDCMP_MENUPICK: */
|
||||
UWORD code = imsg->Code;
|
||||
while (code != MENUNULL) {
|
||||
struct MenuItem *item = ItemAddress(menu, code);
|
||||
UWORD menuNum = MENUNUM(code);
|
||||
UWORD itemNum = ITEMNUM(code);
|
||||
UWORD subNum = SUBNUM(code);
|
||||
/* process selection */
|
||||
code = item->NextSelect;
|
||||
{ NM_TITLE, "Edit", NULL, 0, 0, NULL },
|
||||
{ NM_ITEM, "Cut", "X", 0, 0, (APTR)MENU_CUT },
|
||||
{ NM_ITEM, "Copy", "C", 0, 0, (APTR)MENU_COPY },
|
||||
{ NM_ITEM, "Paste", "V", 0, 0, (APTR)MENU_PASTE },
|
||||
{ NM_ITEM, NM_BARLABEL, NULL, 0, 0, NULL },
|
||||
{ NM_ITEM, "Select All", "A", NM_COMMANDSTRING, 0, (APTR)MENU_SELECTALL },
|
||||
|
||||
{ NM_TITLE, "Style", NULL, 0, 0, NULL },
|
||||
{ NM_ITEM, "Bold", "B", CHECKIT|MENUTOGGLE, 0, (APTR)MENU_BOLD },
|
||||
{ NM_ITEM, "Italic", "I", CHECKIT|MENUTOGGLE, 0, (APTR)MENU_ITALIC },
|
||||
{ NM_ITEM, "Underline", "U", CHECKIT|MENUTOGGLE, 0, (APTR)MENU_UNDERLINE },
|
||||
|
||||
{ NM_END, NULL, NULL, 0, 0, NULL }
|
||||
};
|
||||
```
|
||||
|
||||
### NewMenu Field Reference
|
||||
|
||||
| Field | Description |
|
||||
|---|---|
|
||||
| `nm_Type` | `NM_TITLE`, `NM_ITEM`, `NM_SUB`, or `NM_END` |
|
||||
| `nm_Label` | Text label, or `NM_BARLABEL` for separator |
|
||||
| `nm_CommKey` | Keyboard shortcut character (Right-Amiga + key) |
|
||||
| `nm_Flags` | `CHECKIT`, `CHECKED`, `MENUTOGGLE`, `NM_COMMANDSTRING`, `NM_ITEMDISABLED` |
|
||||
| `nm_MutualExclude` | Bitmask of items that can't be checked simultaneously |
|
||||
| `nm_UserData` | Application-defined value — typically a menu command ID |
|
||||
|
||||
### Creating and Attaching
|
||||
|
||||
```c
|
||||
/* Get VisualInfo for the screen */
|
||||
struct Screen *scr = LockPubScreen(NULL);
|
||||
APTR vi = GetVisualInfo(scr, TAG_DONE);
|
||||
|
||||
/* Create the menu structure */
|
||||
struct Menu *menuStrip = CreateMenus(nm, TAG_DONE);
|
||||
if (!menuStrip) { /* error */ }
|
||||
|
||||
/* Layout the menus (calculates positions/sizes) */
|
||||
if (!LayoutMenus(menuStrip, vi, GTMN_NewLookMenus, TRUE, TAG_DONE))
|
||||
{
|
||||
FreeMenus(menuStrip);
|
||||
/* error */
|
||||
}
|
||||
|
||||
/* Cleanup: */
|
||||
/* Attach to window */
|
||||
SetMenuStrip(win, menuStrip);
|
||||
|
||||
/* Cleanup (in reverse order): */
|
||||
ClearMenuStrip(win);
|
||||
FreeMenus(menu);
|
||||
FreeMenus(menuStrip);
|
||||
FreeVisualInfo(vi);
|
||||
UnlockPubScreen(NULL, scr);
|
||||
```
|
||||
|
||||
---
|
||||
|
||||
## Menu Selection Macros
|
||||
## Handling Menu Events
|
||||
|
||||
### Basic Event Loop
|
||||
|
||||
Menu selections arrive as `IDCMP_MENUPICK` events. The `Code` field contains a **packed menu number**:
|
||||
|
||||
```c
|
||||
#define MENUNUM(code) ((code) & 0x1F) /* menu number (0–31) */
|
||||
#define ITEMNUM(code) (((code) >> 5) & 0x3F) /* item number (0–63) */
|
||||
#define SUBNUM(code) (((code) >> 11) & 0x1F) /* subitem number */
|
||||
#define FULLMENUNUM(m,i,s) ((m)|((i)<<5)|((s)<<11))
|
||||
#define MENUNULL 0xFFFF /* no selection */
|
||||
case IDCMP_MENUPICK:
|
||||
{
|
||||
UWORD menuCode = code;
|
||||
|
||||
while (menuCode != MENUNULL)
|
||||
{
|
||||
struct MenuItem *item = ItemAddress(menuStrip, menuCode);
|
||||
|
||||
/* Decode menu/item/sub numbers */
|
||||
UWORD menuNum = MENUNUM(menuCode);
|
||||
UWORD itemNum = ITEMNUM(menuCode);
|
||||
UWORD subNum = SUBNUM(menuCode);
|
||||
|
||||
/* Use UserData for command dispatch (cleaner than numbers) */
|
||||
APTR userData = GTMENUITEM_USERDATA(item);
|
||||
|
||||
switch ((ULONG)userData)
|
||||
{
|
||||
case MENU_NEW: NewDocument(); break;
|
||||
case MENU_OPEN: OpenDocument(); break;
|
||||
case MENU_SAVE: SaveDocument(); break;
|
||||
case MENU_QUIT: running = FALSE; break;
|
||||
case MENU_CUT: CutSelection(); break;
|
||||
case MENU_COPY: CopySelection(); break;
|
||||
case MENU_PASTE: PasteClipboard(); break;
|
||||
|
||||
case MENU_BOLD:
|
||||
/* Check if item is now checked or unchecked */
|
||||
if (item->Flags & CHECKED)
|
||||
EnableBold();
|
||||
else
|
||||
DisableBold();
|
||||
break;
|
||||
}
|
||||
|
||||
/* Multi-select: user may have selected multiple items
|
||||
by holding the right button while clicking */
|
||||
menuCode = item->NextSelect;
|
||||
}
|
||||
break;
|
||||
}
|
||||
```
|
||||
|
||||
### Menu Number Encoding
|
||||
|
||||
Menu selections are encoded as a single `UWORD`:
|
||||
|
||||
```c
|
||||
/* Decode macros */
|
||||
#define MENUNUM(code) ((code) & 0x1F) /* Bits 0–4: menu (0–31) */
|
||||
#define ITEMNUM(code) (((code) >> 5) & 0x3F) /* Bits 5–10: item (0–63) */
|
||||
#define SUBNUM(code) (((code) >> 11) & 0x1F) /* Bits 11–15: sub (0–31) */
|
||||
|
||||
/* Encode macro */
|
||||
#define FULLMENUNUM(m, i, s) ((m) | ((i) << 5) | ((s) << 11))
|
||||
|
||||
/* No selection */
|
||||
#define MENUNULL 0xFFFF
|
||||
```
|
||||
|
||||
### Multi-Select
|
||||
|
||||
The Amiga supports **multi-select**: the user can hold the right button and select multiple items in sequence. Each selected item's `NextSelect` field points to the next selection in the chain. You **must** walk this chain — otherwise, multi-selected items are silently dropped.
|
||||
|
||||
---
|
||||
|
||||
## Checkmark and Mutual Exclusion
|
||||
|
||||
### Toggle Menus
|
||||
|
||||
Items with `CHECKIT | MENUTOGGLE` act as toggles:
|
||||
|
||||
```c
|
||||
{ NM_ITEM, "Word Wrap", NULL, CHECKIT | MENUTOGGLE | CHECKED, 0, (APTR)MENU_WORDWRAP },
|
||||
```
|
||||
|
||||
- `CHECKED` — item starts checked
|
||||
- `MENUTOGGLE` — clicking toggles between checked/unchecked
|
||||
- Without `MENUTOGGLE`, `CHECKIT` items are one-way (once checked, stay checked)
|
||||
|
||||
### Mutual Exclusion
|
||||
|
||||
Force radio-button behavior by setting `nm_MutualExclude` to a bitmask of incompatible items:
|
||||
|
||||
```c
|
||||
/* Only one tab size can be active at a time */
|
||||
{ NM_ITEM, "Tab: 2", NULL, CHECKIT|CHECKED, ~1, (APTR)MENU_TAB2 }, /* Excludes items 1,2 */
|
||||
{ NM_ITEM, "Tab: 4", NULL, CHECKIT, ~2, (APTR)MENU_TAB4 }, /* Excludes items 0,2 */
|
||||
{ NM_ITEM, "Tab: 8", NULL, CHECKIT, ~4, (APTR)MENU_TAB8 }, /* Excludes items 0,1 */
|
||||
```
|
||||
|
||||
The bitmask uses **item positions within the menu** (not IDs). Bit 0 = first item, bit 1 = second item, etc. `~1` means "exclude all except item 0."
|
||||
|
||||
---
|
||||
|
||||
## Sub-Menus
|
||||
|
||||
```c
|
||||
{ NM_TITLE, "Export", NULL, 0, 0, NULL },
|
||||
{ NM_ITEM, "Image", NULL, 0, 0, NULL },
|
||||
{ NM_SUB, "PNG", NULL, 0, 0, (APTR)MENU_PNG },
|
||||
{ NM_SUB, "JPEG", NULL, 0, 0, (APTR)MENU_JPEG },
|
||||
{ NM_SUB, "IFF ILBM", NULL, 0, 0, (APTR)MENU_ILBM },
|
||||
{ NM_ITEM, "Text", "T", 0, 0, (APTR)MENU_TEXT },
|
||||
```
|
||||
|
||||
Sub-menus appear as a cascading menu to the right when the user hovers over the parent item. Only one level of sub-menus is supported.
|
||||
|
||||
---
|
||||
|
||||
## Dynamic Menu Modification
|
||||
|
||||
### Disabling/Enabling Items at Runtime
|
||||
|
||||
```c
|
||||
/* Disable "Save" when no document is open */
|
||||
OffMenu(win, FULLMENUNUM(0, 2, NOSUB)); /* Menu 0, Item 2 */
|
||||
|
||||
/* Enable "Paste" when clipboard has content */
|
||||
OnMenu(win, FULLMENUNUM(1, 2, NOSUB)); /* Menu 1, Item 2 */
|
||||
```
|
||||
|
||||
### Checking/Unchecking Items
|
||||
|
||||
```c
|
||||
struct MenuItem *item = ItemAddress(menuStrip,
|
||||
FULLMENUNUM(2, 0, NOSUB));
|
||||
|
||||
/* Check programmatically */
|
||||
item->Flags |= CHECKED;
|
||||
|
||||
/* Uncheck */
|
||||
item->Flags &= ~CHECKED;
|
||||
```
|
||||
|
||||
### Replacing the Entire Menu Strip
|
||||
|
||||
```c
|
||||
ClearMenuStrip(win);
|
||||
/* Modify or rebuild menuStrip */
|
||||
SetMenuStrip(win, menuStrip);
|
||||
```
|
||||
|
||||
---
|
||||
|
||||
## Keyboard Shortcuts
|
||||
|
||||
### Standard Single-Character Shortcuts
|
||||
|
||||
The `nm_CommKey` field accepts a single character. Intuition displays it as "Amiga+X" in the menu:
|
||||
|
||||
```c
|
||||
{ NM_ITEM, "Open...", "O", 0, 0, (APTR)MENU_OPEN },
|
||||
/* Displayed as: Open... ⌂O */
|
||||
```
|
||||
|
||||
### Multi-Character Shortcuts (NM_COMMANDSTRING)
|
||||
|
||||
For longer key descriptions (non-standard shortcuts):
|
||||
|
||||
```c
|
||||
{ NM_ITEM, "Find Next", "F3", NM_COMMANDSTRING, 0, (APTR)MENU_FINDNEXT },
|
||||
/* NM_COMMANDSTRING tells GadTools to display the full string as-is */
|
||||
```
|
||||
|
||||
> **Note**: `NM_COMMANDSTRING` only changes the display text. You must still handle the actual key detection in your `IDCMP_RAWKEY` handler — GadTools does not intercept arbitrary key combinations.
|
||||
|
||||
---
|
||||
|
||||
## Menu Imagery (Advanced)
|
||||
|
||||
Menu items can contain images instead of text:
|
||||
|
||||
```c
|
||||
/* Image-based menu item */
|
||||
struct Image *icon = /* ... your image ... */;
|
||||
|
||||
struct MenuItem imgItem = {
|
||||
.NextItem = NULL,
|
||||
.LeftEdge = 0,
|
||||
.TopEdge = 0,
|
||||
.Width = icon->Width,
|
||||
.Height = icon->Height,
|
||||
.Flags = ITEMTEXT | ITEMENABLED | HIGHCOMP,
|
||||
.MutualExclude = 0,
|
||||
.ItemFill = (APTR)icon,
|
||||
.SelectFill = NULL,
|
||||
.Command = 0,
|
||||
.SubItem = NULL,
|
||||
.NextSelect = MENUNULL,
|
||||
};
|
||||
```
|
||||
|
||||
However, GadTools' `CreateMenus()` does not support image items — this requires manual `struct Menu`/`MenuItem` construction.
|
||||
|
||||
---
|
||||
|
||||
## Pitfalls
|
||||
|
||||
### 1. Not Walking NextSelect
|
||||
|
||||
```c
|
||||
/* BUG — only handles first selection, drops multi-select */
|
||||
struct MenuItem *item = ItemAddress(menuStrip, code);
|
||||
HandleItem(item);
|
||||
/* Missing: code = item->NextSelect; loop */
|
||||
```
|
||||
|
||||
### 2. ClearMenuStrip Before Closing Window
|
||||
|
||||
If you call `CloseWindow()` without `ClearMenuStrip()` first, Intuition may access freed menu memory during the close process.
|
||||
|
||||
```c
|
||||
/* CORRECT order */
|
||||
ClearMenuStrip(win);
|
||||
CloseWindow(win);
|
||||
FreeMenus(menuStrip);
|
||||
```
|
||||
|
||||
### 3. LayoutMenus with Wrong VisualInfo
|
||||
|
||||
The VisualInfo must match the screen the window is on. Using a VisualInfo from a different screen causes corrupted menu rendering.
|
||||
|
||||
### 4. Modifying Menu Strip While Active
|
||||
|
||||
Never modify `struct MenuItem` fields while the menu strip is attached to a window. Always `ClearMenuStrip()` first, modify, then `SetMenuStrip()` again.
|
||||
|
||||
### 5. Shortcut Key Collisions
|
||||
|
||||
Intuition automatically intercepts Right-Amiga+key combinations matching menu shortcuts. If two items share the same shortcut letter, only the first match is triggered.
|
||||
|
||||
---
|
||||
|
||||
## Best Practices
|
||||
|
||||
1. **Use `GTMENUITEM_USERDATA()`** for command dispatch — more robust than position-based menu/item numbers
|
||||
2. **Always walk `NextSelect`** to handle multi-select properly
|
||||
3. **Use `NM_BARLABEL`** to visually group related items with separators
|
||||
4. **Follow platform conventions**: Project menu first, Quit at bottom with separator, Edit menu second
|
||||
5. **Use `MENUTOGGLE`** for boolean settings — users expect toggle behavior
|
||||
6. **Disable items** with `OffMenu()` when they don't apply — don't hide them
|
||||
7. **Clean up in order**: `ClearMenuStrip()` → `CloseWindow()` → `FreeMenus()` → `FreeVisualInfo()`
|
||||
8. **Use `GTMN_NewLookMenus, TRUE`** for the modern 3D menu appearance (OS 3.0+)
|
||||
|
||||
---
|
||||
|
||||
## References
|
||||
|
||||
- NDK39: `libraries/gadtools.h`, `intuition/intuition.h`
|
||||
- ADCD 2.1: `CreateMenus`, `LayoutMenus`, `SetMenuStrip`
|
||||
- NDK 3.9: `intuition/intuition.h`, `libraries/gadtools.h`
|
||||
- ADCD 2.1: `CreateMenus()`, `LayoutMenus()`, `SetMenuStrip()`, `ClearMenuStrip()`, `FreeMenus()`
|
||||
- AmigaOS Reference Manual (RKRM): Libraries, Chapter 6 — Menus
|
||||
- See also: [IDCMP](idcmp.md), [Windows](windows.md), [GadTools (Gadgets)](gadgets.md)
|
||||
|
|
|
|||
|
|
@ -1,70 +1,370 @@
|
|||
[← Home](../README.md) · [Intuition](README.md)
|
||||
|
||||
# Requesters — EasyRequest, AutoRequest, ASL File Requester
|
||||
# Requesters
|
||||
|
||||
## Overview
|
||||
## What Is a Requester?
|
||||
|
||||
Requesters are modal dialog boxes. Intuition provides `EasyRequest` for simple dialogs; `asl.library` provides file/font/screen-mode requesters.
|
||||
A requester is a **modal dialog** — a focused interaction that temporarily blocks user access to its parent window until the user responds. Amiga requesters come in several flavors:
|
||||
|
||||
| Type | API | Use Case |
|
||||
|---|---|---|
|
||||
| **EasyRequest** | `EasyRequest()` / `EasyRequestArgs()` | Simple message dialogs (alerts, confirmations) |
|
||||
| **AutoRequest** | `AutoRequest()` | Legacy OS 1.x two-button dialog |
|
||||
| **ASL File** | `asl.library` — `ASL_FileRequest` | File open/save dialogs |
|
||||
| **ASL Font** | `asl.library` — `ASL_FontRequest` | Font picker |
|
||||
| **ASL ScreenMode** | `asl.library` — `ASL_ScreenModeRequest` | Display mode picker |
|
||||
| **Custom** | `Request()` / BOOPSI | Application-defined forms |
|
||||
|
||||
---
|
||||
|
||||
## EasyRequest (OS 2.0+)
|
||||
|
||||
The standard way to show message dialogs — supports printf-style formatting and arbitrary button layouts:
|
||||
|
||||
### Basic Usage
|
||||
|
||||
```c
|
||||
struct EasyStruct es = {
|
||||
sizeof(struct EasyStruct),
|
||||
0,
|
||||
"Warning", /* title */
|
||||
"Delete file '%s'?", /* body (printf format) */
|
||||
"Yes|No|Cancel" /* button labels (| separated) */
|
||||
0, /* Flags (reserved) */
|
||||
"Warning", /* Window title */
|
||||
"Delete file '%s'?\n"
|
||||
"This action cannot be undone.", /* Body text (printf format) */
|
||||
"Delete|Cancel" /* Button labels (| separated) */
|
||||
};
|
||||
|
||||
LONG result = EasyRequest(win, &es, NULL, filename);
|
||||
/* Returns: 1=Yes, 0=Cancel, 2=No (rightmost non-zero, leftmost=0) */
|
||||
/* For Yes|No: 1=Yes, 0=No */
|
||||
```
|
||||
|
||||
### Return Value Logic
|
||||
|
||||
The return value mapping is **not intuitive** — it follows a specific pattern:
|
||||
|
||||
| Buttons | Click | Return Value |
|
||||
|---|---|---|
|
||||
| `"OK"` | OK | `1` |
|
||||
| `"Yes\|No"` | Yes | `1` |
|
||||
| `"Yes\|No"` | No | `0` |
|
||||
| `"Save\|Don't Save\|Cancel"` | Save | `1` |
|
||||
| `"Save\|Don't Save\|Cancel"` | Don't Save | `2` |
|
||||
| `"Save\|Don't Save\|Cancel"` | Cancel | `0` |
|
||||
|
||||
**Rule**: The **rightmost button always returns 0** (typically "Cancel"). All other buttons return 1, 2, 3... from left to right.
|
||||
|
||||
### Printf-Style Formatting
|
||||
|
||||
The body text supports `%s`, `%ld`, `%lx`, etc. Additional arguments are passed after the `IDCMP_Ptr` parameter:
|
||||
|
||||
```c
|
||||
struct EasyStruct es = {
|
||||
sizeof(struct EasyStruct), 0,
|
||||
"Disk Error",
|
||||
"Error %ld occurred while\n"
|
||||
"reading '%s' from %s:",
|
||||
"Retry|Abort"
|
||||
};
|
||||
|
||||
/* Pass format arguments as varargs */
|
||||
LONG result = EasyRequest(win, &es, NULL,
|
||||
errorCode, /* %ld */
|
||||
fileName, /* %s */
|
||||
deviceName /* %s */
|
||||
);
|
||||
```
|
||||
|
||||
### Non-Blocking Variant
|
||||
|
||||
```c
|
||||
/* For situations where you can't block (e.g., input handler): */
|
||||
struct Window *reqWin = BuildEasyRequest(win, &es, IDCMP_DISKINSERTED, args);
|
||||
|
||||
/* Poll for response (returns -1 while still open): */
|
||||
LONG response;
|
||||
while ((response = SysReqHandler(reqWin, NULL, FALSE)) == -1)
|
||||
{
|
||||
/* Do other work or Wait() */
|
||||
Wait(1L << reqWin->UserPort->mp_SigBit);
|
||||
}
|
||||
FreeSysRequest(reqWin);
|
||||
```
|
||||
|
||||
---
|
||||
|
||||
## ASL File Requester
|
||||
|
||||
The standard file open/save dialog provided by `asl.library`:
|
||||
|
||||
### Opening a File
|
||||
|
||||
```c
|
||||
#include <libraries/asl.h>
|
||||
#include <proto/asl.h>
|
||||
|
||||
struct Library *AslBase = OpenLibrary("asl.library", 39);
|
||||
|
||||
struct FileRequester *fr = AllocAslRequestTags(ASL_FileRequest,
|
||||
ASLFR_TitleText, "Open File",
|
||||
ASLFR_InitialDrawer, "SYS:",
|
||||
ASLFR_InitialPattern, "#?.txt",
|
||||
ASLFR_DoPatterns, TRUE,
|
||||
ASLFR_TitleText, "Open File",
|
||||
ASLFR_InitialDrawer, "SYS:Docs",
|
||||
ASLFR_InitialFile, "",
|
||||
ASLFR_InitialPattern, "#?.(txt|doc|guide)",
|
||||
ASLFR_DoPatterns, TRUE, /* Show pattern gadget */
|
||||
ASLFR_DoMultiSelect, FALSE, /* Single file selection */
|
||||
ASLFR_RejectIcons, TRUE, /* Hide .info files */
|
||||
TAG_DONE);
|
||||
|
||||
if (AslRequest(fr, NULL)) {
|
||||
Printf("Selected: %s%s\n", fr->fr_Drawer, fr->fr_File);
|
||||
if (AslRequest(fr, NULL))
|
||||
{
|
||||
/* User clicked "OK" */
|
||||
char fullPath[512];
|
||||
strcpy(fullPath, fr->fr_Drawer);
|
||||
AddPart(fullPath, fr->fr_File, sizeof(fullPath));
|
||||
Printf("Selected: %s\n", fullPath);
|
||||
}
|
||||
else
|
||||
{
|
||||
/* User clicked "Cancel" */
|
||||
}
|
||||
|
||||
FreeAslRequest(fr);
|
||||
CloseLibrary(AslBase);
|
||||
```
|
||||
|
||||
### Save Dialog
|
||||
|
||||
```c
|
||||
struct FileRequester *fr = AllocAslRequestTags(ASL_FileRequest,
|
||||
ASLFR_TitleText, "Save As...",
|
||||
ASLFR_InitialDrawer, currentDrawer,
|
||||
ASLFR_InitialFile, currentFile,
|
||||
ASLFR_DoSaveMode, TRUE, /* "Save" button instead of "Open" */
|
||||
ASLFR_DoPatterns, TRUE,
|
||||
TAG_DONE);
|
||||
```
|
||||
|
||||
### Multi-Select
|
||||
|
||||
```c
|
||||
struct FileRequester *fr = AllocAslRequestTags(ASL_FileRequest,
|
||||
ASLFR_TitleText, "Select Files",
|
||||
ASLFR_DoMultiSelect, TRUE,
|
||||
TAG_DONE);
|
||||
|
||||
if (AslRequest(fr, NULL))
|
||||
{
|
||||
if (fr->fr_NumArgs > 0)
|
||||
{
|
||||
/* Multi-select: iterate the WBArg array */
|
||||
for (LONG i = 0; i < fr->fr_NumArgs; i++)
|
||||
{
|
||||
Printf("File: %s\n", fr->fr_ArgList[i].wa_Name);
|
||||
}
|
||||
}
|
||||
else
|
||||
{
|
||||
/* Single file selected (even in multi-select mode) */
|
||||
Printf("File: %s%s\n", fr->fr_Drawer, fr->fr_File);
|
||||
}
|
||||
}
|
||||
```
|
||||
|
||||
### Common ASL File Tags
|
||||
|
||||
| Tag | Type | Description |
|
||||
|---|---|---|
|
||||
| `ASLFR_TitleText` | `STRPTR` | Requester window title |
|
||||
| `ASLFR_InitialDrawer` | `STRPTR` | Starting directory |
|
||||
| `ASLFR_InitialFile` | `STRPTR` | Pre-selected filename |
|
||||
| `ASLFR_InitialPattern` | `STRPTR` | AmigaOS pattern filter (e.g., `#?.txt`) |
|
||||
| `ASLFR_DoPatterns` | `BOOL` | Show pattern matching gadget |
|
||||
| `ASLFR_DoSaveMode` | `BOOL` | Show "Save" button instead of "Open" |
|
||||
| `ASLFR_DoMultiSelect` | `BOOL` | Allow multiple file selection |
|
||||
| `ASLFR_RejectIcons` | `BOOL` | Hide `.info` icon files |
|
||||
| `ASLFR_DrawersOnly` | `BOOL` | Only show directories (folder picker) |
|
||||
| `ASLFR_InitialLeftEdge/TopEdge` | `WORD` | Requester position |
|
||||
| `ASLFR_InitialWidth/Height` | `WORD` | Requester size |
|
||||
| `ASLFR_Window` | `struct Window *` | Parent window (for positioning) |
|
||||
| `ASLFR_Screen` | `struct Screen *` | Screen to open on |
|
||||
| `ASLFR_FilterFunc` | `struct Hook *` | Custom filtering function |
|
||||
|
||||
---
|
||||
|
||||
## ASL Font Requester
|
||||
|
||||
```c
|
||||
struct FontRequester *fo = AllocAslRequestTags(ASL_FontRequest,
|
||||
ASLFO_TitleText, "Select Font",
|
||||
ASLFO_InitialName, "topaz.font",
|
||||
ASLFO_InitialSize, 8,
|
||||
ASLFO_DoStyle, TRUE,
|
||||
ASLFO_TitleText, "Select Font",
|
||||
ASLFO_InitialName, "topaz.font",
|
||||
ASLFO_InitialSize, 8,
|
||||
ASLFO_DoFrontPen, TRUE, /* Show color picker */
|
||||
ASLFO_DoStyle, TRUE, /* Show Bold/Italic/Underline */
|
||||
ASLFO_DoDrawMode, TRUE, /* Show JAM1/JAM2 selector */
|
||||
ASLFO_MinHeight, 6, /* Minimum font size */
|
||||
ASLFO_MaxHeight, 72, /* Maximum font size */
|
||||
TAG_DONE);
|
||||
|
||||
if (AslRequest(fo, NULL)) {
|
||||
if (AslRequest(fo, NULL))
|
||||
{
|
||||
Printf("Font: %s %ld\n", fo->fo_Attr.ta_Name, fo->fo_Attr.ta_YSize);
|
||||
Printf("Style: %ld, FrontPen: %ld\n", fo->fo_Attr.ta_Style, fo->fo_FrontPen);
|
||||
|
||||
/* Open the selected font */
|
||||
struct TextFont *font = OpenDiskFont(&fo->fo_Attr);
|
||||
if (font)
|
||||
{
|
||||
SetFont(win->RPort, font);
|
||||
/* ... */
|
||||
CloseFont(font);
|
||||
}
|
||||
}
|
||||
FreeAslRequest(fo);
|
||||
```
|
||||
|
||||
---
|
||||
|
||||
## ASL ScreenMode Requester
|
||||
|
||||
For applications that let users choose their display mode:
|
||||
|
||||
```c
|
||||
struct ScreenModeRequester *smr = AllocAslRequestTags(ASL_ScreenModeRequest,
|
||||
ASLSM_TitleText, "Select Screen Mode",
|
||||
ASLSM_InitialDisplayID, HIRES_KEY,
|
||||
ASLSM_InitialDisplayDepth, 4,
|
||||
ASLSM_DoWidth, TRUE, /* Allow width selection */
|
||||
ASLSM_DoHeight, TRUE, /* Allow height selection */
|
||||
ASLSM_DoDepth, TRUE, /* Allow depth selection */
|
||||
ASLSM_DoOverscanType, TRUE, /* Allow overscan selection */
|
||||
ASLSM_MinWidth, 320,
|
||||
ASLSM_MinHeight, 200,
|
||||
ASLSM_MinDepth, 1,
|
||||
ASLSM_MaxDepth, 8,
|
||||
TAG_DONE);
|
||||
|
||||
if (AslRequest(smr, NULL))
|
||||
{
|
||||
Printf("Mode: 0x%08lx, %ldx%ldx%ld\n",
|
||||
smr->sm_DisplayID,
|
||||
smr->sm_DisplayWidth,
|
||||
smr->sm_DisplayHeight,
|
||||
smr->sm_DisplayDepth);
|
||||
|
||||
/* Open screen with selected mode */
|
||||
struct Screen *scr = OpenScreenTags(NULL,
|
||||
SA_DisplayID, smr->sm_DisplayID,
|
||||
SA_Width, smr->sm_DisplayWidth,
|
||||
SA_Height, smr->sm_DisplayHeight,
|
||||
SA_Depth, smr->sm_DisplayDepth,
|
||||
SA_Overscan, smr->sm_OverscanType,
|
||||
SA_AutoScroll, TRUE,
|
||||
TAG_DONE);
|
||||
}
|
||||
FreeAslRequest(smr);
|
||||
```
|
||||
|
||||
---
|
||||
|
||||
## Custom Window Requesters
|
||||
|
||||
For application-specific forms, use `Request()` with a custom layout:
|
||||
|
||||
```c
|
||||
/* Create a requester with gadgets */
|
||||
struct Requester req;
|
||||
InitRequester(&req);
|
||||
|
||||
req.LeftEdge = 20;
|
||||
req.TopEdge = 20;
|
||||
req.Width = 300;
|
||||
req.Height = 100;
|
||||
req.ReqGadget = myGadgetList; /* Your gadgets */
|
||||
req.ReqText = myIntuiText; /* Labels */
|
||||
req.BackFill = 0; /* Background pen */
|
||||
req.Flags = 0;
|
||||
req.ReqBorder = myBorder; /* Border decoration */
|
||||
|
||||
/* Activate the requester (blocks the parent window) */
|
||||
if (Request(&req, win))
|
||||
{
|
||||
/* Requester is active — handle IDCMP_GADGETUP events */
|
||||
/* When done: */
|
||||
EndRequest(&req, win);
|
||||
}
|
||||
```
|
||||
|
||||
> Most modern applications use `EasyRequest()` for simple dialogs or build custom windows instead of `Request()`. The `Request()` API is mainly relevant for legacy code.
|
||||
|
||||
---
|
||||
|
||||
## Remembering Requester State
|
||||
|
||||
ASL requesters remember their last position and selections if you reuse the same requester structure:
|
||||
|
||||
```c
|
||||
/* Allocate once at program start */
|
||||
struct FileRequester *fr = AllocAslRequestTags(ASL_FileRequest,
|
||||
ASLFR_TitleText, "Open", TAG_DONE);
|
||||
|
||||
/* First use — shows default directory */
|
||||
AslRequest(fr, NULL);
|
||||
|
||||
/* Second use — automatically shows the directory from last use */
|
||||
AslRequest(fr, NULL);
|
||||
|
||||
/* Free at program exit */
|
||||
FreeAslRequest(fr);
|
||||
```
|
||||
|
||||
You can override this with explicit tags on each call:
|
||||
|
||||
```c
|
||||
AslRequest(fr, (struct TagItem *)(APTR[]){
|
||||
{ ASLFR_InitialDrawer, (ULONG)"RAM:" },
|
||||
{ TAG_DONE, 0 }
|
||||
});
|
||||
```
|
||||
|
||||
---
|
||||
|
||||
## Pitfalls
|
||||
|
||||
### 1. EasyRequest Return Value Confusion
|
||||
|
||||
The rightmost button always returns 0, not the button count. For `"Yes|No"`, "No" returns 0 — which many developers mistake for FALSE when it's actually the "No" response.
|
||||
|
||||
### 2. ASL Without a Window Reference
|
||||
|
||||
If you don't pass `ASLFR_Window`, the requester opens at a default position, potentially on a different screen or off-screen.
|
||||
|
||||
### 3. Not Checking AslRequest Return
|
||||
|
||||
`AslRequest()` returns FALSE if the user cancels. Always check — accessing `fr->fr_File` after cancellation returns the previous (stale) selection.
|
||||
|
||||
### 4. Forgetting FreeAslRequest
|
||||
|
||||
ASL requesters allocate internal memory for file lists and paths. Failing to call `FreeAslRequest()` leaks memory.
|
||||
|
||||
### 5. Blocking While Requester Is Open
|
||||
|
||||
EasyRequest and AslRequest are **synchronous** — your event loop is stopped while the requester is open. If you need to handle background events, use the non-blocking `BuildEasyRequest()`/`SysReqHandler()` pattern.
|
||||
|
||||
---
|
||||
|
||||
## Best Practices
|
||||
|
||||
1. **Use `EasyRequest()`** for all message dialogs — not `AutoRequest()` (OS 1.x legacy)
|
||||
2. **Place "Cancel" as the rightmost button** — it always returns 0, matching the Amiga convention
|
||||
3. **Pass the parent window** to requesters — for proper screen placement and depth arrangement
|
||||
4. **Reuse ASL requesters** — users expect the dialog to remember their last directory
|
||||
5. **Use `ASLFR_DoPatterns, TRUE`** — power users rely on pattern matching
|
||||
6. **Use `ASLFR_RejectIcons, TRUE`** — `.info` files clutter the file list
|
||||
7. **Use `BuildEasyRequest()`** when you need to handle events during a dialog
|
||||
8. **Always check return values** — a canceled requester should not proceed with the operation
|
||||
|
||||
---
|
||||
|
||||
## References
|
||||
|
||||
- NDK39: `intuition/intuition.h`, `libraries/asl.h`
|
||||
- ADCD 2.1: `EasyRequest`, `AslRequest`
|
||||
- NDK 3.9: `intuition/intuition.h`, `libraries/asl.h`
|
||||
- ADCD 2.1: `EasyRequest()`, `AllocAslRequest()`, `AslRequest()`, `FreeAslRequest()`
|
||||
- AmigaOS Reference Manual (RKRM): Libraries, Chapter 9 — Requesters
|
||||
- See also: [Windows](windows.md), [Gadgets](gadgets.md), [IDCMP](idcmp.md)
|
||||
|
|
|
|||
|
|
@ -1,97 +1,370 @@
|
|||
[← Home](../README.md) · [Intuition](README.md)
|
||||
|
||||
# Windows — OpenWindow, IDCMP, WA_ Tags
|
||||
# Windows
|
||||
|
||||
## Overview
|
||||
## What Is a Window?
|
||||
|
||||
A **Window** is a rectangular region on a Screen where an application renders and receives input. Windows are managed by Intuition and provide title bars, borders, close/zoom/depth gadgets, sizing, and IDCMP message delivery.
|
||||
A window is Intuition's fundamental unit of user interaction. Every GUI element — gadgets, menus, text, graphics — lives inside a window. A window belongs to exactly one [screen](screens.md), receives user input through [IDCMP](idcmp.md), and is managed by the system's layered display architecture.
|
||||
|
||||
Unlike modern windowing systems where windows are heavyweight objects backed by compositor surfaces, Amiga windows are **lightweight wrappers around Layers** — the graphics.library's clipping and damage-tracking mechanism. This is why a 7 MHz 68000 can manage dozens of overlapping windows smoothly.
|
||||
|
||||
---
|
||||
|
||||
## Opening a Window (OS 2.0+)
|
||||
## Window Anatomy
|
||||
|
||||
```mermaid
|
||||
graph TB
|
||||
subgraph "Window Structure"
|
||||
TITLE["Title Bar (drag area)"]
|
||||
CLOSE["×"]
|
||||
DEPTH["⊡"]
|
||||
ZOOM["□"]
|
||||
BORDER_L["Left Border"]
|
||||
CONTENT["Content Area<br/>(your drawing region)"]
|
||||
BORDER_R["Right Border"]
|
||||
SIZE["Size Gadget ◢"]
|
||||
BOTTOM["Bottom Border"]
|
||||
end
|
||||
|
||||
style TITLE fill:#e8f4fd,stroke:#2196f3,color:#333
|
||||
style CONTENT fill:#fff,stroke:#bdbdbd,color:#333
|
||||
style CLOSE fill:#ffebee,stroke:#f44336,color:#333
|
||||
style DEPTH fill:#e8f5e9,stroke:#4caf50,color:#333
|
||||
style SIZE fill:#fff3e0,stroke:#ff9800,color:#333
|
||||
```
|
||||
|
||||
| Element | System Gadget | Purpose |
|
||||
|---|---|---|
|
||||
| **Close** | `WFLG_CLOSEGADGET` | Sends `IDCMP_CLOSEWINDOW` |
|
||||
| **Depth** | `WFLG_DEPTHGADGET` | Moves window front/back |
|
||||
| **Zoom** | `WFLG_HASZOOM` (OS 2.0+) | Toggles between two sizes |
|
||||
| **Drag Bar** | `WFLG_DRAGBAR` | User drags the window |
|
||||
| **Size** | `WFLG_SIZEGADGET` | Resize handle (bottom-right) |
|
||||
| **Borders** | Automatic | Visual frame; width depends on screen resolution |
|
||||
|
||||
---
|
||||
|
||||
## Opening a Window
|
||||
|
||||
### Modern Pattern (OS 2.0+ TagList)
|
||||
|
||||
```c
|
||||
struct Window *win = OpenWindowTags(NULL,
|
||||
WA_Left, 50,
|
||||
WA_Top, 30,
|
||||
WA_Width, 400,
|
||||
WA_Height, 200,
|
||||
WA_Title, "My Window",
|
||||
WA_Flags, WFLG_CLOSEGADGET | WFLG_DRAGBAR | WFLG_DEPTHGADGET |
|
||||
WFLG_SIZEGADGET | WFLG_ACTIVATE | WFLG_GIMMEZEROZERO,
|
||||
WA_IDCMP, IDCMP_CLOSEWINDOW | IDCMP_MOUSEBUTTONS | IDCMP_VANILLAKEY,
|
||||
WA_CustomScreen, myScreen,
|
||||
WA_Left, 100,
|
||||
WA_Top, 50,
|
||||
WA_InnerWidth, 400, /* Content area width */
|
||||
WA_InnerHeight, 300, /* Content area height */
|
||||
WA_Title, "My Window",
|
||||
WA_ScreenTitle, "Status bar text when this window is active",
|
||||
WA_IDCMP, IDCMP_CLOSEWINDOW | IDCMP_GADGETUP |
|
||||
IDCMP_RAWKEY | IDCMP_NEWSIZE,
|
||||
WA_Flags, WFLG_CLOSEGADGET | WFLG_DRAGBAR |
|
||||
WFLG_DEPTHGADGET | WFLG_SIZEGADGET |
|
||||
WFLG_ACTIVATE | WFLG_SMART_REFRESH,
|
||||
WA_MinWidth, 200,
|
||||
WA_MinHeight, 100,
|
||||
WA_MaxWidth, -1, /* No maximum (screen width) */
|
||||
WA_MaxHeight, -1, /* No maximum (screen height) */
|
||||
WA_PubScreen, NULL, /* Default public screen (Workbench) */
|
||||
TAG_DONE);
|
||||
|
||||
if (!win) { /* Handle failure — screen may be locked or out of memory */ }
|
||||
```
|
||||
|
||||
### Common WA_ Tags
|
||||
|
||||
| Tag | Description |
|
||||
|---|---|
|
||||
| `WA_Left`, `WA_Top` | Position |
|
||||
| `WA_Width`, `WA_Height` | Size |
|
||||
| `WA_MinWidth`, `WA_MaxWidth` | Size limits |
|
||||
| `WA_Title` | Window title string |
|
||||
| `WA_Flags` | `WFLG_*` flags |
|
||||
| `WA_IDCMP` | IDCMP class mask |
|
||||
| `WA_CustomScreen` | Screen to open on |
|
||||
| `WA_PubScreen` | Public screen to open on |
|
||||
| `WA_SuperBitMap` | Use super-bitmap scrolling |
|
||||
| `WA_Gadgets` | First gadget in chain |
|
||||
| `WA_Checkmark` | Custom checkmark image |
|
||||
| `WA_Borderless` | No borders |
|
||||
|
||||
---
|
||||
|
||||
## Window Flags (`WFLG_*`)
|
||||
### Legacy Pattern (struct NewWindow)
|
||||
|
||||
```c
|
||||
#define WFLG_SIZEGADGET (1<<0)
|
||||
#define WFLG_DRAGBAR (1<<1)
|
||||
#define WFLG_DEPTHGADGET (1<<2)
|
||||
#define WFLG_CLOSEGADGET (1<<3)
|
||||
#define WFLG_SIZEBRIGHT (1<<4) /* right-side sizing */
|
||||
#define WFLG_SIZEBBOTTOM (1<<5)
|
||||
#define WFLG_SMART_REFRESH (0) /* refresh type */
|
||||
#define WFLG_SIMPLE_REFRESH (1<<6)
|
||||
#define WFLG_SUPER_BITMAP (1<<7)
|
||||
#define WFLG_BACKDROP (1<<8)
|
||||
#define WFLG_REPORTMOUSE (1<<9)
|
||||
#define WFLG_GIMMEZEROZERO (1<<10) /* inner area starts at 0,0 */
|
||||
#define WFLG_BORDERLESS (1<<11)
|
||||
#define WFLG_ACTIVATE (1<<12)
|
||||
#define WFLG_RMBTRAP (1<<16) /* trap right-button clicks */
|
||||
#define WFLG_NOCAREREFRESH (1<<17)
|
||||
/* Pre-OS 2.0 — avoid in new code */
|
||||
struct NewWindow nw = {
|
||||
100, 50, 400, 300, /* Left, Top, Width, Height */
|
||||
0, 1, /* DetailPen, BlockPen */
|
||||
IDCMP_CLOSEWINDOW, /* IDCMPFlags */
|
||||
WFLG_CLOSEGADGET | WFLG_DRAGBAR | WFLG_ACTIVATE,
|
||||
NULL, NULL, /* FirstGadget, CheckMark */
|
||||
"My Window", /* Title */
|
||||
NULL, NULL, /* Screen, BitMap */
|
||||
200, 100, -1, -1, /* Min/Max Width/Height */
|
||||
WBENCHSCREEN /* Type */
|
||||
};
|
||||
struct Window *win = OpenWindow(&nw);
|
||||
```
|
||||
|
||||
---
|
||||
|
||||
## Event Loop
|
||||
## Common WA_ Tags
|
||||
|
||||
### Position and Size
|
||||
|
||||
| Tag | Type | Description |
|
||||
|---|---|---|
|
||||
| `WA_Left`, `WA_Top` | `WORD` | Window position (outer edge) |
|
||||
| `WA_Width`, `WA_Height` | `WORD` | Total window size (including borders) |
|
||||
| `WA_InnerWidth`, `WA_InnerHeight` | `WORD` | Content area size (excluding borders) — preferred |
|
||||
| `WA_MinWidth`, `WA_MinHeight` | `WORD` | Minimum resize dimensions |
|
||||
| `WA_MaxWidth`, `WA_MaxHeight` | `WORD` | Maximum resize dimensions; `-1` = screen size |
|
||||
| `WA_Zoom` | `WORD[4]` | Alternate position/size for zoom gadget |
|
||||
|
||||
### Appearance
|
||||
|
||||
| Tag | Type | Description |
|
||||
|---|---|---|
|
||||
| `WA_Title` | `STRPTR` | Title bar text |
|
||||
| `WA_ScreenTitle` | `STRPTR` | Screen title shown when this window is active |
|
||||
| `WA_Borderless` | `BOOL` | No borders or system gadgets |
|
||||
| `WA_GimmeZeroZero` | `BOOL` | Inner content area starts at (0,0) — adds extra layer |
|
||||
| `WA_NoCareRefresh` | `BOOL` | Ignore REFRESHWINDOW — Intuition handles it (may cause glitches) |
|
||||
|
||||
### Screen Placement
|
||||
|
||||
| Tag | Type | Description |
|
||||
|---|---|---|
|
||||
| `WA_PubScreen` | `struct Screen *` | Open on a public screen (`NULL` = default/Workbench) |
|
||||
| `WA_CustomScreen` | `struct Screen *` | Open on a custom (private) screen |
|
||||
| `WA_PubScreenName` | `STRPTR` | Open on named public screen; falls back to default |
|
||||
| `WA_PubScreenFallBack` | `BOOL` | If named screen unavailable, use default |
|
||||
|
||||
### Behavior
|
||||
|
||||
| Tag | Type | Description |
|
||||
|---|---|---|
|
||||
| `WA_Activate` | `BOOL` | Window becomes active immediately on open |
|
||||
| `WA_Backdrop` | `BOOL` | Always stays behind all normal windows |
|
||||
| `WA_SmartRefresh` | `BOOL` | Intuition saves obscured content automatically |
|
||||
| `WA_SimpleRefresh` | `BOOL` | Application must redraw on expose (less memory) |
|
||||
| `WA_SuperBitMap` | `struct BitMap *` | Application provides full off-screen buffer |
|
||||
| `WA_AutoAdjust` | `BOOL` | Auto-adjust position/size to fit screen |
|
||||
| `WA_NewLookMenus` | `BOOL` | OS 3.0+ 3D menu appearance |
|
||||
|
||||
---
|
||||
|
||||
## Refresh Modes
|
||||
|
||||
How Intuition handles window content when areas are obscured and then revealed:
|
||||
|
||||
| Mode | Flag | Memory Cost | App Responsibility | Best For |
|
||||
|---|---|---|---|---|
|
||||
| **Simple Refresh** | `WFLG_SIMPLE_REFRESH` | Lowest | Must handle `IDCMP_REFRESHWINDOW` — redraw exposed areas | Text editors, games (redraw every frame anyway) |
|
||||
| **Smart Refresh** | `WFLG_SMART_REFRESH` | Medium | Intuition saves/restores obscured areas automatically | Most applications — recommended default |
|
||||
| **SuperBitMap** | `WFLG_SUPER_BITMAP` | Highest | Application provides full-size `BitMap`; Intuition copies from it | CAD, paint programs with large canvases |
|
||||
|
||||
### Simple Refresh Handler
|
||||
|
||||
```c
|
||||
case IDCMP_REFRESHWINDOW:
|
||||
BeginRefresh(win);
|
||||
/* Redraw only the damaged region — clipping is set automatically */
|
||||
RedrawWindowContents(win);
|
||||
EndRefresh(win, TRUE); /* TRUE = damage fully repaired */
|
||||
break;
|
||||
```
|
||||
|
||||
### Smart Refresh Memory Cost
|
||||
|
||||
Smart Refresh allocates off-screen buffers proportional to the **obscured area**. If a 640×400 window is 50% covered by other windows, Smart Refresh consumes ~128 KB (at 4 bitplanes). On a 512 KB A500, this is significant.
|
||||
|
||||
---
|
||||
|
||||
## Window Types
|
||||
|
||||
### Standard Window
|
||||
|
||||
The default — has borders, title bar, and system gadgets:
|
||||
|
||||
```c
|
||||
WA_Flags, WFLG_CLOSEGADGET | WFLG_DRAGBAR |
|
||||
WFLG_DEPTHGADGET | WFLG_SIZEGADGET | WFLG_ACTIVATE,
|
||||
```
|
||||
|
||||
### Backdrop Window
|
||||
|
||||
Stays behind all other windows. Commonly used for:
|
||||
- Desktop manager backgrounds
|
||||
- Full-screen applications that want to coexist with Workbench windows
|
||||
|
||||
```c
|
||||
WA_Flags, WFLG_BACKDROP | WFLG_BORDERLESS | WFLG_ACTIVATE,
|
||||
WA_IDCMP, IDCMP_MOUSEBUTTONS | IDCMP_RAWKEY,
|
||||
```
|
||||
|
||||
### Borderless Window
|
||||
|
||||
No system gadgets or decorations — the application draws everything:
|
||||
|
||||
```c
|
||||
WA_Borderless, TRUE,
|
||||
WA_Flags, WFLG_ACTIVATE | WFLG_RMBTRAP, /* Trap right-click too */
|
||||
```
|
||||
|
||||
### GimmeZeroZero Window
|
||||
|
||||
Creates a separate layer for window borders. The content area's `RastPort` starts at (0,0) regardless of border width:
|
||||
|
||||
```c
|
||||
WA_Flags, WFLG_GIMMEZEROZERO | WFLG_CLOSEGADGET | WFLG_DRAGBAR,
|
||||
```
|
||||
|
||||
**Trade-off**: Uses an extra layer (memory + blitter operations) but simplifies rendering code since you don't need to account for border offsets.
|
||||
|
||||
### Sizing Constraints
|
||||
|
||||
```c
|
||||
WA_MinWidth, 200,
|
||||
WA_MinHeight, 100,
|
||||
WA_MaxWidth, -1, /* Screen width */
|
||||
WA_MaxHeight, -1, /* Screen height */
|
||||
WA_SizeGadget, TRUE,
|
||||
WA_SizeBRight, TRUE, /* Size gadget on right border */
|
||||
WA_SizeBBottom, TRUE, /* Size gadget on bottom border */
|
||||
```
|
||||
|
||||
---
|
||||
|
||||
## Window Coordinates
|
||||
|
||||
### Border Offsets
|
||||
|
||||
The content area does NOT start at (0,0) in a normal window. You must account for borders:
|
||||
|
||||
```c
|
||||
WORD contentLeft = win->BorderLeft;
|
||||
WORD contentTop = win->BorderTop;
|
||||
WORD contentWidth = win->Width - win->BorderLeft - win->BorderRight;
|
||||
WORD contentHeight = win->Height - win->BorderTop - win->BorderBottom;
|
||||
|
||||
/* Draw at content origin */
|
||||
Move(win->RPort, contentLeft, contentTop + baseline);
|
||||
Text(win->RPort, "Hello", 5);
|
||||
```
|
||||
|
||||
With `WFLG_GIMMEZEROZERO`, the window provides a separate `GZZWidth`/`GZZHeight` and a content `RastPort` where (0,0) is the content origin.
|
||||
|
||||
---
|
||||
|
||||
## Closing a Window
|
||||
|
||||
### Simple Case
|
||||
|
||||
```c
|
||||
BOOL running = TRUE;
|
||||
while (running) {
|
||||
WaitPort(win->UserPort);
|
||||
struct IntuiMessage *imsg;
|
||||
while ((imsg = (struct IntuiMessage *)GetMsg(win->UserPort))) {
|
||||
switch (imsg->Class) {
|
||||
case IDCMP_CLOSEWINDOW:
|
||||
running = FALSE;
|
||||
break;
|
||||
case IDCMP_VANILLAKEY:
|
||||
Printf("Key: %lc\n", imsg->Code);
|
||||
break;
|
||||
}
|
||||
ReplyMsg((struct Message *)imsg);
|
||||
}
|
||||
}
|
||||
CloseWindow(win);
|
||||
```
|
||||
|
||||
### Safe Shutdown (Drain Messages First)
|
||||
|
||||
```c
|
||||
/* Drain any pending IDCMP messages */
|
||||
struct IntuiMessage *msg;
|
||||
while ((msg = (struct IntuiMessage *)GetMsg(win->UserPort)))
|
||||
ReplyMsg((struct Message *)msg);
|
||||
|
||||
CloseWindow(win);
|
||||
```
|
||||
|
||||
### With Shared Port
|
||||
|
||||
See [IDCMP — Multi-Window Shared Port](idcmp.md#multi-window-shared-port) for the full `Forbid()`/strip/detach protocol.
|
||||
|
||||
---
|
||||
|
||||
## Modifying a Window
|
||||
|
||||
### Move and Resize
|
||||
|
||||
```c
|
||||
MoveWindow(win, deltaX, deltaY); /* Relative move */
|
||||
SizeWindow(win, deltaWidth, deltaHeight); /* Relative resize */
|
||||
ChangeWindowBox(win, left, top, w, h); /* Absolute reposition + resize */
|
||||
WindowToFront(win);
|
||||
WindowToBack(win);
|
||||
ActivateWindow(win);
|
||||
```
|
||||
|
||||
### Change Title
|
||||
|
||||
```c
|
||||
SetWindowTitles(win, "New Title", "New Screen Title");
|
||||
/* Pass (UBYTE *)-1 to leave unchanged */
|
||||
SetWindowTitles(win, "New Title", (UBYTE *)-1);
|
||||
```
|
||||
|
||||
### Busy Pointer
|
||||
|
||||
```c
|
||||
/* OS 3.0+ — show busy pointer */
|
||||
SetWindowPointer(win, WA_BusyPointer, TRUE, TAG_DONE);
|
||||
|
||||
/* Restore normal pointer */
|
||||
SetWindowPointer(win, WA_Pointer, NULL, TAG_DONE);
|
||||
```
|
||||
|
||||
---
|
||||
|
||||
## struct Window — Key Fields
|
||||
|
||||
| Field | Type | Description |
|
||||
|---|---|---|
|
||||
| `LeftEdge`, `TopEdge` | `WORD` | Position on screen |
|
||||
| `Width`, `Height` | `WORD` | Total size (including borders) |
|
||||
| `BorderLeft/Right/Top/Bottom` | `BYTE` | Border thickness (pixels) |
|
||||
| `RPort` | `struct RastPort *` | Drawing context for this window |
|
||||
| `UserPort` | `struct MsgPort *` | IDCMP message port |
|
||||
| `IDCMPFlags` | `ULONG` | Currently active IDCMP flags |
|
||||
| `Flags` | `ULONG` | Window flags (`WFLG_*`) |
|
||||
| `Title` | `UBYTE *` | Title string |
|
||||
| `WScreen` | `struct Screen *` | Screen this window belongs to |
|
||||
| `FirstGadget` | `struct Gadget *` | Head of gadget list |
|
||||
| `MouseX`, `MouseY` | `WORD` | Current mouse position (relative to window) |
|
||||
| `GZZWidth`, `GZZHeight` | `WORD` | Inner dimensions (GimmeZeroZero only) |
|
||||
| `MinWidth/Height`, `MaxWidth/Height` | `WORD` | Size constraints |
|
||||
|
||||
---
|
||||
|
||||
## Pitfalls
|
||||
|
||||
### 1. Using WA_Width Instead of WA_InnerWidth
|
||||
|
||||
`WA_Width` includes borders. On different screen resolutions, border width varies. Always use `WA_InnerWidth`/`WA_InnerHeight` for predictable content area sizing.
|
||||
|
||||
### 2. Drawing Outside Content Area
|
||||
|
||||
Drawing at (0,0) in a non-GZZ window overwrites the border:
|
||||
```c
|
||||
/* WRONG — draws over title bar */
|
||||
Move(win->RPort, 0, 10);
|
||||
|
||||
/* CORRECT — offset by borders */
|
||||
Move(win->RPort, win->BorderLeft, win->BorderTop + 10);
|
||||
```
|
||||
|
||||
### 3. Forgetting MinWidth/MinHeight
|
||||
|
||||
Without size constraints, users can resize the window to 1×1 pixel, causing division-by-zero in layout code.
|
||||
|
||||
### 4. Not Handling NEWSIZE
|
||||
|
||||
If your window is resizable, you must redraw content when `IDCMP_NEWSIZE` arrives — the old content is clipped or garbage.
|
||||
|
||||
### 5. Opening on a Closed Screen
|
||||
|
||||
If you cache a screen pointer and it becomes invalid, `OpenWindowTags()` will crash. Always `LockPubScreen()` → open window → `UnlockPubScreen()`.
|
||||
|
||||
---
|
||||
|
||||
## Best Practices
|
||||
|
||||
1. **Use `WA_InnerWidth`/`WA_InnerHeight`** for predictable content dimensions
|
||||
2. **Use Smart Refresh** unless you have a specific reason not to
|
||||
3. **Always set `WA_MinWidth`/`WA_MinHeight`** for resizable windows
|
||||
4. **Handle `IDCMP_NEWSIZE`** — recalculate and redraw layout
|
||||
5. **Use `WA_PubScreen, NULL`** to open on the default public screen
|
||||
6. **Drain IDCMP messages** before calling `CloseWindow()`
|
||||
7. **Show a busy pointer** during long operations — it prevents user confusion
|
||||
8. **Use `WA_AutoAdjust, TRUE`** to handle cases where the window doesn't fit the screen
|
||||
|
||||
---
|
||||
|
||||
## References
|
||||
|
||||
- NDK39: `intuition/intuition.h`
|
||||
- ADCD 2.1: `OpenWindowTagList`, `CloseWindow`
|
||||
- [idcmp.md](idcmp.md) — IDCMP message classes
|
||||
- NDK 3.9: `intuition/intuition.h`, `intuition/screens.h`
|
||||
- ADCD 2.1: `OpenWindowTagList()`, `CloseWindow()`, `ModifyIDCMP()`
|
||||
- AmigaOS Reference Manual (RKRM): Libraries, Chapter 4 — Intuition Windows
|
||||
- See also: [IDCMP](idcmp.md), [Screens](screens.md), [Gadgets](gadgets.md)
|
||||
|
|
|
|||
Loading…
Add table
Add a link
Reference in a new issue