Preview: promote selected layer for hit testing

Temporarily raise the selected preview item and prioritize it in the custom hit test without changing scene order. Refresh integration-test expectations for Brand logo layers and explicit thumbnail assets. WPF references: https://learn.microsoft.com/en-us/dotnet/api/system.windows.controls.panel.zindex?view=windowsdesktop-10.0 https://learn.microsoft.com/en-us/dotnet/desktop/wpf/graphics-multimedia/hit-testing-in-the-visual-layer
2026-10-28 13:09:15 -07:00
parent 7da287244b
commit 769c616706
13 changed files with 326 additions and 79 deletions
@@ -0,0 +1,118 @@
+using System;
+using System.Linq;
+using System.Windows;
+using System.Windows.Controls;
+using System.Windows.Media;
+using Microsoft.Data.Sqlite;
+using Xunit;
+using ytLive.Controls;
+using ytLive.Models;
+using ytLive.Services;
+using ytLive.ViewModels;
+
+namespace ytLive.Tests;
+
+[Collection("RealApp")]
+public sealed class SelectedLayerPreviewHitTestingTests
+{
+    private readonly RealAppHost _app;
+
+    public SelectedLayerPreviewHitTestingTests(RealAppHost app) => _app = app;
+
+    [Fact]
+    public void ListSelectedBrandLogo_WinsPreviewHitTesting_UntilDeselected()
+    {
+        _app.Run(Run);
+    }
+
+    private static void Run()
+    {
+        var tempDb = System.IO.Path.Combine(System.IO.Path.GetTempPath(), $"ytLlive-selected-layer-{Guid.NewGuid():N}.db");
+        MainViewModel.LayoutPathOverride = tempDb;
+        MainWindow? window = null;
+        try
+        {
+            using (var schema = new LayoutStore(tempDb)) { }
+            SqliteConnection.ClearAllPools();
+
+            window = new MainWindow();
+            var vm = (MainViewModel)window.DataContext;
+            var scene = vm.StagedScene!;
+            var logo = scene.Elements.OfType<Source>().Single(source => source.IsBrandLogo);
+            logo.X = 420;
+            logo.Y = 300;
+            logo.Width = 300;
+            logo.Height = 180;
+
+            var webcam = new WebcamSceneConfig
+            {
+                WebcamId = "test-camera",
+                Name = "Webcam",
+                X = logo.X,
+                Y = logo.Y,
+                Width = logo.Width,
+                Height = logo.Height,
+            };
+            scene.Elements.Add(webcam);
+            var originalOrder = scene.Elements.ToArray();
+
+            window.Show();
+            window.Activate();
+            window.Topmost = true;
+            window.UpdateLayout();
+
+            var leftPanel = (LeftPanel)window.FindName("LeftPanel")!;
+            var sourceList = (ListBox)leftPanel.FindName("SourceList")!;
+            var preview = (PreviewPane)window.FindName("PreviewPane")!;
+            var canvasGrid = (FrameworkElement)preview.FindName("CanvasGrid")!;
+            var overlayElements = (ItemsControl)preview.FindName("OverlayElements")!;
+            var logoContainer = (UIElement)overlayElements.ItemContainerGenerator.ContainerFromItem(logo)!;
+            var webcamContainer = (UIElement)overlayElements.ItemContainerGenerator.ContainerFromItem(webcam)!;
+            var pointInCanvas = new Point(logo.X + 100, logo.Y + 60);
+            var pointInWindow = canvasGrid.TransformToVisual(window).Transform(pointInCanvas);
+
+            Assert.True(ReferenceEquals(webcam, ElementAt(window.InputHitTest(pointInWindow))));
+            Assert.Same(webcam, preview.HitElementAt(vm, pointInCanvas));
+            Assert.Equal(0, Panel.GetZIndex(logoContainer));
+
+            sourceList.SelectedItem = logo;
+            window.UpdateLayout();
+
+            Assert.True(ReferenceEquals(logo, vm.SelectedElement), "Selecting the layer-list row must select the brand logo.");
+            Assert.True(Panel.GetZIndex(logoContainer) > Panel.GetZIndex(webcamContainer));
+            Assert.Same(logo, ElementAt(window.InputHitTest(pointInWindow)));
+            Assert.Same(logo, preview.HitElementAt(vm, pointInCanvas));
+            Assert.Equal(originalOrder, scene.Elements);
+
+            sourceList.SelectedItem = null;
+            window.UpdateLayout();
+
+            Assert.Null(vm.SelectedElement);
+            Assert.Equal(0, Panel.GetZIndex(logoContainer));
+            Assert.Same(webcam, ElementAt(window.InputHitTest(pointInWindow)));
+            Assert.Same(webcam, preview.HitElementAt(vm, pointInCanvas));
+            Assert.Equal(originalOrder, scene.Elements);
+        }
+        finally
+        {
+            window?.Close();
+            MainViewModel.LayoutPathOverride = null;
+            SqliteConnection.ClearAllPools();
+            try { System.IO.File.Delete(tempDb); } catch { }
+        }
+    }
+
+    private static SceneElement? ElementAt(System.Windows.IInputElement? hit)
+    {
+        DependencyObject? current = hit as DependencyObject;
+        while (current != null)
+        {
+            if (current is FrameworkElement { DataContext: SceneElement element })
+                return element;
+            current = current is Visual or System.Windows.Media.Media3D.Visual3D
+                ? VisualTreeHelper.GetParent(current)
+                : LogicalTreeHelper.GetParent(current);
+        }
+        return null;
+    }
+}