Material3.Avalonia

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Platforms ​

The theme is pure managed code on top of Avalonia — the same package runs on desktop, Android, iOS and WebAssembly. The repo's samples/ folder is a working reference for all four heads sharing one UI project.

samples/
├── Material3.Gallery.UI/        shared UserControl UI (App + MainView)
├── Material3.Gallery/           desktop head (NativeAOT in Release)
├── Material3.Gallery.Android/   net10.0-android
├── Material3.Gallery.iOS/       net10.0-ios
└── Material3.Gallery.Browser/   net10.0-browser (WASM)

Desktop ​

Nothing special — apply the theme and go. The sample publishes as a single-file NativeAOT binary:

bash
dotnet publish samples/Material3.Gallery -c Release -r osx-arm64 --self-contained

The library declares IsAotCompatible and uses zero reflection, so trimming/AOT work out of the box.

Single-view platforms (Android / iOS / Browser) ​

Support both lifetimes in your App:

csharp
public override void OnFrameworkInitializationCompleted()
{
    if (ApplicationLifetime is IClassicDesktopStyleApplicationLifetime desktop)
        desktop.MainWindow = new MainWindow();
    else if (ApplicationLifetime is ISingleViewApplicationLifetime singleView)
        singleView.MainView = new MainView();   // a UserControl

    base.OnFrameworkInitializationCompleted();
}

Android ​

bash
dotnet build samples/Material3.Gallery.Android -t:Run   # device or emulator attached
  • The activity must use an AppCompat theme (Theme.AppCompat.DayNight.NoActionBar), because AvaloniaActivity derives from AppCompatActivity.
  • minSdk 23+.

iOS ​

bash
dotnet build samples/Material3.Gallery.iOS -t:Run       # simulator

WebAssembly ​

bash
dotnet run --project samples/Material3.Gallery.Browser

Program.cs is three lines:

csharp
public static Task Main(string[] args) => BuildAvaloniaApp()
    .WithInterFont()
    .StartBrowserAppAsync("out");   // mounts into <div id="out"> in index.html

public static AppBuilder BuildAvaloniaApp() => AppBuilder.Configure<App>();

A hosted AOT build of the gallery is available as the live demo. GitHub Pages serves precompressed .br resources through the browser's native Brotli DecompressionStream, with automatic fallback to uncompressed resources.

Touch adaptation notes ​

  • All interactive controls meet the 48dp touch-target metric (Md3MinTouchTarget).
  • Ripples originate at the touch point and cancel automatically when a scroll gesture takes over the pointer.
  • For phone layouts, pair the theme with SplitView (overlay drawer + hamburger) as shown in MainView.axaml — the gallery switches automatically below 900 px width.