CompositionCollectionView 0.2.0

CompositionCollectionView

A composition-driven collection view control for UWP and WinUI 3 / Windows App SDK, with fully customizable layouts and behaviors powered by Windows.UI.Composition.

Features

• Composition-powered animations — all element positioning, scaling, rotation, and opacity are driven by composition expression animations for smooth 60fps performance
• Custom layouts — extend CompositionCollectionLayout<TId, TItem> to define how elements are positioned, scaled, and rotated
• Animated layout transitions — smoothly animate between different layouts with TransitionTo()
• Behaviors — attach reusable behaviors like InteractionTrackerBehavior for gesture-driven interactions
• Interaction tracker gestures — define composable touch/pointer gestures with visual previews
• Multi-platform — ships as a single NuGet package targeting both UWP (uap10.0.19041) and WinUI 3 (net9.0-windows10.0.19041.0)

Quick Start

<labs:CompositionCollectionView x:Name="collectionView"
                                Width="600" Height="200" />

// Define a simple horizontal layout
public class HorizontalLayout : CompositionCollectionLayout<uint, MyItem>
{
    public HorizontalLayout(Func<uint, FrameworkElement> factory) : base(factory) { }

    public override Vector3Node GetElementPositionNode(ElementReference<uint, MyItem> element)
        => ExpressionFunctions.Vector3(element.Id * 120, 0, 0);
}

// Create and use the layout
var layout = new HorizontalLayout(id => new MyItemControl());
collectionView.SetLayout(layout);
await collectionView.UpdateSource(myItems);

Solution Structure

CompositionCollectionView/
├── src/CompositionCollectionView/          # Control library (UWP + WinUI 3)
├── samples/
│   ├── CompositionCollectionView.Sample.Uwp/       # UWP sample app
│   └── CompositionCollectionView.Sample.WinUI3/    # WinUI 3 sample app

Building

Build with Visual Studio 2022+ or MSBuild:

msbuild CompositionCollectionView.sln /p:Platform=x64

Architecture

CompositionCollectionLayout

The core abstract class you extend to define layouts. Override these methods:

Behaviors

Attach CompositionCollectionLayoutBehavior<TId, TItem> instances to layouts for reusable functionality:

• InteractionTrackerBehavior — wraps VisualInteractionSource + InteractionTracker for gesture handling
• ElementInteractionTrackerBehavior — per-element interaction trackers
• InteractionTrackerGesture — composable gesture definitions with visual previews

ExpressionsFork

An internal fork of the Windows Community Toolkit's expression animation helpers, with added Evaluate() method support.

CompositionExpressions (standalone expression-DSL packages)

The typed expression-animation DSL (ExpressionsFork — ScalarNode, Matrix4x4Node, ExpressionFunctions, .Evaluate(), plus the animatable-node wrappers) is also published on its own, so you can compose CompositionObject expression animations without taking a dependency on the collection-view control.

Which package you need depends on two independent axes — the target-framework era and the composition surface your app renders on:

• arcadiog.CompositionExpressions — the mainstream package. Ships a UWP asset (system composition, for UWP apps) and a net10.0-windows asset that binds to the lifted Microsoft.UI.Composition and depends on the Windows App SDK. Use it from WinUI 3 / Windows App SDK apps.

• arcadiog.CompositionExpressions.SystemComp — for .NET 5+ hosts that render on the system compositor (Windows.UI.Composition on a DesktopWindowTarget), e.g. a transparent per-pixel-alpha window created outside the XAML/WinUI stack. This is the one asset the mainstream package can't provide: its UWP asset trips NETSDK1149 when consumed from .NET 5+, and its lifted net10.0-windows asset is the wrong composition surface and drags in the Windows App SDK.

  It compiles the same DSL source, but with a distinct assembly name (CompositionExpressions.SystemComp) so a single app can reference both flavors at once — e.g. lifted composition for its main WinUI window and system composition for a headless/transparent companion window — without a CompositionExpressions.dll output collision.

License

MIT