Wpf: Maintain focus of Tree/GridView after ReloadItem/ReloadData

picoe · Apr 2, 2024 · bbc87c5 · bbc87c5
1 parent 398327f
commit bbc87c5
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Showing 5 changed files with 109 additions and 12 deletions.
diff --git a/src/Eto.WinForms/CustomControls/TreeController.cs b/src/Eto.WinForms/CustomControls/TreeController.cs
@@ -3,11 +3,11 @@ namespace Eto.CustomControls
 	public interface ITreeHandler
 	{
 		ITreeGridItem SelectedItem { get; }
-		void SelectRow (int row);
+		void SelectRow(int row);
 		bool AllowMultipleSelection { get; }
 
-		void PreResetTree ();
-		void PostResetTree ();
+		bool PreResetTree(object item = null, int row = -1);
+		void PostResetTree(object item = null, int row = -1);
 	}
 
 	public class TreeController : ITreeGridStore<ITreeGridItem>, IList, INotifyCollectionChanged
@@ -316,20 +316,20 @@ bool ChildIsSelected (ITreeGridItem item)
 
 		void ResetCollection ()
 		{
-			if (parent == null)
-				Handler.PreResetTree ();
-			OnTriggerCollectionChanged (new NotifyCollectionChangedEventArgs (NotifyCollectionChangedAction.Reset));
-			if (parent == null)
-				Handler.PostResetTree ();
+			var doPost = parent == null && Handler.PreResetTree();
+			OnTriggerCollectionChanged(new NotifyCollectionChangedEventArgs (NotifyCollectionChangedAction.Reset));
+			if (doPost) Handler.PostResetTree ();
 		}
 
 		public void ReloadItem(ITreeGridItem item)
 		{
 			var row = IndexOf(item);
 			if (row < 0)
 				return;
+			var doPost = parent == null && Handler.PreResetTree(item, row);
 			OnTriggerCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Remove, item, row));
 			OnTriggerCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Add, item, row));
+			if (doPost) Handler.PostResetTree(item, row);
 		}
 
 		public bool CollapseRow (int row)

diff --git a/src/Eto.WinForms/Forms/Controls/TreeGridViewHandler.cs b/src/Eto.WinForms/Forms/Controls/TreeGridViewHandler.cs
@@ -351,11 +351,12 @@ void AutoSizeColumns(bool displayedOnly)
 			}
 		}
 
-		void ITreeHandler.PreResetTree()
+		bool ITreeHandler.PreResetTree(object item, int row)
 		{
+			return false;
 		}
 
-		void ITreeHandler.PostResetTree()
+		void ITreeHandler.PostResetTree(object item, int row)
 		{
 		}
 

diff --git a/src/Eto.Wpf/Forms/Controls/GridHandler.cs b/src/Eto.Wpf/Forms/Controls/GridHandler.cs
@@ -939,7 +939,15 @@ public BorderType Border
 
 		public void ReloadData(IEnumerable<int> rows)
 		{
+			SkipSelectionChanged = true;
+			SaveFocus();
+
 			Control.Items.Refresh();
+
+			DisableAutoScrollToSelection = true;
+			RestoreFocus();
+			SkipSelectionChanged = false;
+			DisableAutoScrollToSelection = false;
 		}
 
 		swc.DataGridRow GetCurrentRow()

diff --git a/src/Eto.Wpf/Forms/Controls/TreeGridViewHandler.cs b/src/Eto.Wpf/Forms/Controls/TreeGridViewHandler.cs
@@ -189,13 +189,16 @@ public override sw.FrameworkElement SetupCell(IGridColumnHandler column, sw.Fram
 			return new TreeTogglePanel(defaultContent, controller);
 		}
 
-		void ITreeHandler.PreResetTree()
+		bool ITreeHandler.PreResetTree(object item, int row)
 		{
+			if (item != null && Control.CurrentItem != item)
+				return false;
 			SkipSelectionChanged = true;
 			SaveFocus();
+			return true;
 		}
 
-		void ITreeHandler.PostResetTree()
+		void ITreeHandler.PostResetTree(object item, int row)
 		{
 			DisableAutoScrollToSelection = true;
 			RestoreFocus();

diff --git a/test/Eto.Test/UnitTests/Forms/Controls/GridTests.cs b/test/Eto.Test/UnitTests/Forms/Controls/GridTests.cs
@@ -491,5 +491,90 @@ public void AutoSizedColumnShouldChangeSizeOfControl(string text, int rows, int
 				return layout;
 			});
 		}
+
+		[Test]
+		public void ReloadingFocusedItemShouldKeepFocus()
+		{
+			bool? hasFocusBefore = null;
+			bool? hasFocusAfter = null;
+			Form(form => {
+				var grid = new T();
+				grid.ShowHeader = false;
+				grid.Size = new Size(200, 200);
+				grid.Columns.Add(new GridColumn { DataCell = new TextBoxCell { Binding = Binding.Property((GridTestItem m) => m.Text) } });
+				var dataStore = CreateDataStore();
+				var list = (IList)dataStore;
+				SetDataStore(grid, dataStore);
+				grid.SelectedRow = 1;
+
+				form.Content = grid;
+				var gv = grid as GridView;
+				var tgv = grid as TreeGridView;
+				
+				form.Shown += async (s, e) =>
+				{
+					grid.Focus();
+					await Task.Delay(TimeSpan.FromSeconds(0.1));
+					// first, reload an row that doesn't have focus
+					gv?.ReloadData(0);
+					tgv?.ReloadItem((ITreeGridItem)list[0]);
+
+					await Task.Delay(TimeSpan.FromSeconds(0.1));
+					
+					// We should still have focus, then reload the item that does have focus
+					hasFocusBefore = grid.HasFocus; 
+					gv?.ReloadData(1);
+					tgv?.ReloadItem((ITreeGridItem)list[1]);
+					
+					await Task.Delay(TimeSpan.FromSeconds(0.1));
+					
+					// Focus should still be kept
+					hasFocusAfter = grid.HasFocus;
+					form.Close();
+				};
+			});
+			Assert.IsTrue(hasFocusBefore, "Grid did not have focus before reloading");
+			Assert.IsTrue(hasFocusAfter, "Grid did not have focus after reloading");
+		}
+
+		[Test]
+		public void ReloadingDataShouldKeepFocus()
+		{
+			bool? hasFocusBefore = null;
+			bool? hasFocusAfter = null;
+			Form(form => {
+				var grid = new T();
+				grid.ShowHeader = false;
+				grid.Size = new Size(200, 200);
+				grid.Columns.Add(new GridColumn { DataCell = new TextBoxCell { Binding = Binding.Property((GridTestItem m) => m.Text) } });
+				var dataStore = CreateDataStore();
+				var list = (IList)dataStore;
+				SetDataStore(grid, dataStore);
+				grid.SelectedRow = 1;
+				
+				form.Content = grid;
+				var gv = grid as GridView;
+				var tgv = grid as TreeGridView;
+				
+				form.Shown += async (s, e) =>
+				{
+					grid.Focus();
+					await Task.Delay(TimeSpan.FromSeconds(0.1));
+					
+					// We should still have focus, then reload the data
+					hasFocusBefore = grid.HasFocus; 
+					gv?.ReloadData(Enumerable.Range(0, list.Count));
+					tgv?.ReloadData();
+					
+					await Task.Delay(TimeSpan.FromSeconds(0.1));
+					
+					// Focus should still be kept
+					hasFocusAfter = grid.HasFocus;
+					form.Close();
+				};
+			});
+			Assert.IsTrue(hasFocusBefore, "Grid did not have focus before reloading");
+			Assert.IsTrue(hasFocusAfter, "Grid did not have focus after reloading");
+		}
 	}
 }