Meta - Replace WPF projects with Avalonia projects

src/Artemis.UI/Screens/ProfileEditor/Panels/ProfileTree/ProfileTreeView.axaml.cs

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+using System;
+using System.Diagnostics;
+using Avalonia;
+using Avalonia.Controls;
+using Avalonia.Controls.Primitives;
+using Avalonia.Input;
+using Avalonia.Interactivity;
+using Avalonia.Layout;
+using Avalonia.LogicalTree;
+using Avalonia.Markup.Xaml;
+using Avalonia.Media;
+using Avalonia.Media.Imaging;
+using Avalonia.ReactiveUI;
+using Avalonia.VisualTree;
+
+namespace Artemis.UI.Screens.ProfileEditor.ProfileTree;
+
+public class ProfileTreeView : ReactiveUserControl<ProfileTreeViewModel>
+{
+    private TreeView _treeView;
+    private Image? _dragAdorner;
+    private Point _dragStartPosition;
+    private Point _elementDragOffset;
+
+    public ProfileTreeView()
+    {
+        InitializeComponent();
+        AddHandler(DragDrop.DragEnterEvent, HandleDragEnterEvent, RoutingStrategies.Direct | RoutingStrategies.Tunnel | RoutingStrategies.Bubble, true);
+        AddHandler(DragDrop.DragOverEvent, HandleDragOver, RoutingStrategies.Direct | RoutingStrategies.Tunnel | RoutingStrategies.Bubble, true);
+        AddHandler(PointerEnterEvent, HandlePointerEnter, RoutingStrategies.Direct | RoutingStrategies.Tunnel | RoutingStrategies.Bubble, true);
+    }
+
+    private void HandlePointerEnter(object? sender, PointerEventArgs e)
+    {
+        DisposeDragAdorner();
+    }
+
+    private void HandleDragEnterEvent(object? sender, DragEventArgs e)
+    {
+        CreateDragAdorner(e);
+    }
+
+    private void CreateDragAdorner(DragEventArgs e)
+    {
+        if (_dragAdorner != null)
+            return;
+
+        if (e.Source is not Control c)
+            return;
+
+        // Get the tree view item that raised the event
+        TreeViewItem? container = c.FindLogicalAncestorOfType<TreeViewItem>();
+        if (container == null)
+            return;
+
+        // Take a snapshot of said tree view item and add it as an adorner
+        ITransform? originalTransform = container.RenderTransform;
+        try
+        {
+            _dragStartPosition = e.GetPosition(this.FindAncestorOfType<Window>());
+            _elementDragOffset = e.GetPosition(container);
+
+            RenderTargetBitmap renderTarget = new(new PixelSize((int) container.Bounds.Width, (int) container.Bounds.Height));
+            container.RenderTransform = new TranslateTransform(container.Bounds.X * -1, container.Bounds.Y * -1);
+            renderTarget.Render(container);
+            _dragAdorner = new Image
+            {
+                Source = renderTarget,
+                VerticalAlignment = VerticalAlignment.Top,
+                HorizontalAlignment = HorizontalAlignment.Left,
+                Stretch = Stretch.None,
+                IsHitTestVisible = false
+            };
+            AdornerLayer.GetAdornerLayer(this)!.Children.Add(_dragAdorner);
+        }
+        finally
+        {
+            container.RenderTransform = originalTransform;
+        }
+    }
+
+    private void HandleDragOver(object? sender, DragEventArgs e)
+    {
+        UpdateDragAdorner(e);
+    }
+
+    private void HandleLeaveEvent(object? sender, RoutedEventArgs e)
+    {
+        // If there is currently an adorner, dispose of it
+        DisposeDragAdorner();
+    }
+
+    private void HandleDrop(object? sender, DragEventArgs e)
+    {
+        // If there is currently an adorner, dispose of it
+        DisposeDragAdorner();
+    }
+
+    private void DisposeDragAdorner()
+    {
+        if (_dragAdorner == null)
+            return;
+
+        AdornerLayer.GetAdornerLayer(this)!.Children.Remove(_dragAdorner);
+        (_dragAdorner.Source as RenderTargetBitmap)?.Dispose();
+        _dragAdorner = null;
+    }
+
+    private void UpdateDragAdorner(DragEventArgs e)
+    {
+        if (_dragAdorner == null)
+            return;
+
+        Point position = e.GetPosition(this.FindAncestorOfType<Window>());
+        _dragAdorner.RenderTransform = new TranslateTransform(_dragStartPosition.X - _elementDragOffset.X, position.Y - _elementDragOffset.Y);
+    }
+
+    private void InitializeComponent()
+    {
+        AvaloniaXamlLoader.Load(this);
+        _treeView = this.Get<TreeView>("ProfileTreeView");
+    }
+
+    private void ProfileTreeView_OnSelectionChanged(object? sender, SelectionChangedEventArgs e)
+    {
+        _treeView.Focus();
+    }
+}