> For the complete documentation index, see [llms.txt](https://viridian-games.gitbook.io/pixel-palette/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://viridian-games.gitbook.io/pixel-palette/core-components/appcontext.md).

# AppContext

**AppContext** is a simple message board. Any component can pin itself to the board when it wakes up, and any other component can look it up by type.

#### How it works

```
Awake() → AppContext.Register(this)    // "I exist! Here I am!"
Start() → AppContext.Get<Type>() ??=   // "I need a thing. Anyone?" 
OnDestroy() → AppContext.Unregister(this)  // "I'm gone now"
```

#### Rules

* **Register in `Awake()`** — every component pins itself to the board as soon as it wakes up, before anything tries to use it
* **Resolve in `Start()`** — look up what you need after everything has registered
* **`??=`** — if you already assigned something in the Inspector, that takes priority. AppContext is only a fallback

```
// Example: any script that needs the canvas
private DrawableCanvas canvas;

private void Start()
{
    canvas ??= AppContext.Get<DrawableCanvas>();  // Use the inspector value, or find it from AppContext
}
```

#### What's registered

Every core system registers itself:

```
DrawableCanvas, DrawingSettings, PixelArtFileIO, GridOverlay,
SelectionManager, LayerManager, AnimationManager, 
CanvasInputHandler, CanvasViewController, ConfirmPopupUGUI
```

#### Why not just FindObjectOfType?

`FindObjectOfType` is slow (scans every GameObject in the scene every time). AppContext is instant — it's just a dictionary lookup. Also, `FindObjectOfType` breaks if there are multiple scenes or if the component isn't active yet. AppContext works regardless.


---

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