fix(TreeView): allow dragging and dropping of treeview items

unoplatform · Aug 21, 2023 · 50e0552 · 50e0552
1 parent 36c06c9
commit 50e0552
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Showing 4 changed files with 57 additions and 8 deletions.
diff --git a/src/Uno.UI/Microsoft/UI/Xaml/Controls/TreeView/TreeViewItem.cs b/src/Uno.UI/Microsoft/UI/Xaml/Controls/TreeView/TreeViewItem.cs
@@ -125,7 +125,7 @@ protected override void OnDrop(Windows.UI.Xaml.DragEventArgs args)
 
 							if (droppedNode != droppedOnNode)
 							{
-								((TreeViewNodeVector)droppedOnNode.Parent.Children).RemoveAt(removeIndex);
+								((TreeViewNodeVector)droppedNode.Parent.Children).RemoveAt(removeIndex);
 
 								// Append the dragged dropped item as a child of the node it was dropped onto
 								((TreeViewNodeVector)droppedOnNode.Children).Append(droppedNode);

diff --git a/src/Uno.UI/Microsoft/UI/Xaml/Controls/TreeView/TreeViewList.cs b/src/Uno.UI/Microsoft/UI/Xaml/Controls/TreeView/TreeViewList.cs
@@ -43,7 +43,13 @@ public TreeViewList()
 
 		internal TreeViewViewModel ListViewModel { get; private set; }
 
-		internal TreeViewNode DraggedTreeViewNode { get; private set; }
+		internal TreeViewNode DraggedTreeViewNode
+		{
+			get
+			{
+				return m_draggedTreeViewNode;
+			}
+		}
 
 		private void OnDragItemsStarting(object sender, DragItemsStartingEventArgs args)
 		{

diff --git a/src/Uno.UI/UI/Xaml/Controls/ItemsStackPanel/ItemsStackPanel.cs b/src/Uno.UI/UI/Xaml/Controls/ItemsStackPanel/ItemsStackPanel.cs
@@ -2,12 +2,16 @@
 using System;
 using System.Collections.Generic;
 using System.Text;
+using System.Linq;
 using Uno;
+using Uno.Extensions;
+using Uno.Extensions.Specialized;
 using Uno.UI;
+using Windows.UI.Xaml.Media;
 
 namespace Windows.UI.Xaml.Controls
 {
-	public partial class ItemsStackPanel : Panel, IVirtualizingPanel
+	public partial class ItemsStackPanel : Panel, IVirtualizingPanel, IInsertionPanel
 	{
 		VirtualizingPanelLayout _layout;
 
@@ -58,6 +62,43 @@ private void CreateLayoutIfNeeded()
 #endif
 			}
 		}
+
+		void IInsertionPanel.GetInsertionIndexes(Windows.Foundation.Point position, out int first, out int second)
+		{
+			first = -1;
+			second = -1;
+			if ((new Windows.Foundation.Rect(0, 0, ActualSize.X, ActualSize.Y)).Contains(position))
+			{
+				if (Children == null || Children.Empty())
+				{
+					return;
+				}
+				if (Orientation == Orientation.Vertical)
+				{
+					foreach (var child in Children)
+					{
+						if (position.Y >= child.ActualOffset.Y + child.ActualSize.Y / 2)
+						{
+							first++;
+						}
+					}
+				}
+				else
+				{
+					foreach (var child in Children)
+					{
+						if (position.X >= child.ActualOffset.X + child.ActualSize.X / 2)
+						{
+							first++;
+						}
+					}
+				}
+				if (first + 1 < Children.Count)
+				{
+					second = first + 1;
+				}
+			}
+		}
 	}
 }
 

diff --git a/src/Uno.UI/UI/Xaml/Controls/ListViewBase/ListViewBase.DragDrop.cs b/src/Uno.UI/UI/Xaml/Controls/ListViewBase/ListViewBase.DragDrop.cs
@@ -153,11 +153,13 @@ private static void OnItemContainerDragStarting(UIElement sender, DragStartingEv
 					that.DragLeave -= OnReorderDragLeave;
 					that.Drop -= OnReorderCompleted;
 
-					that.DragEnter += OnReorderDragUpdated;
-					that.DragOver += OnReorderDragUpdated;
-					that.DragLeave += OnReorderDragLeave;
-					that.Drop += OnReorderCompleted;
-
+					if (that is not Microsoft.UI.Xaml.Controls.TreeViewList)
+					{
+						that.DragEnter += OnReorderDragUpdated;
+						that.DragOver += OnReorderDragUpdated;
+						that.DragLeave += OnReorderDragLeave;
+						that.Drop += OnReorderCompleted;
+					}
 					that.m_tpPrimaryDraggedContainer = sender as SelectorItem;
 
 					that.ChangeSelectorItemsVisualState(true);