feat.动画优化与更新界面

LanMountainDesktop.Tests/DesktopEditOverlayPresenterTests.cs

@@ -0,0 +1,38 @@
+using System.Linq;
+using Avalonia;
+using Avalonia.Controls;
+using LanMountainDesktop.DesktopEditing;
+using Xunit;
+
+namespace LanMountainDesktop.Tests;
+
+public sealed class DesktopEditOverlayPresenterTests
+{
+    [Fact]
+    public void CompositionOffsetHelperFallsBackWhenVisualIsUnavailable()
+    {
+        var service = new CompositionVisualAnimationService(_ => null);
+        var target = new Border();
+
+        var result = service.TrySetOffset(target, new Point(12, 34));
+
+        Assert.False(result);
+        Assert.False(service.TrySetOpacity(target, 0.5));
+        Assert.False(service.TrySetUniformScale(target, 1.05));
+    }
+
+    [Fact]
+    public void PreviewRectUsesCanvasPlacementWhenCompositionIsUnavailable()
+    {
+        var presenter = new DesktopEditOverlayPresenter(new CompositionVisualAnimationService(_ => null));
+        var root = Assert.IsType<Canvas>(presenter.Root);
+
+        presenter.SetPreviewRect(new Rect(12, 34, 180, 120));
+
+        var ghost = root.Children.OfType<DesktopEditGhostView>().Single();
+        Assert.Equal(12, Canvas.GetLeft(ghost));
+        Assert.Equal(34, Canvas.GetTop(ghost));
+        Assert.Equal(180, ghost.Width);
+        Assert.Equal(120, ghost.Height);
+    }
+}