Merge pull request #327 from w-ahmad/fix/row_selection

fix: Improve row selection and prevent unnecessary event triggers

Author: w-ahmad

src/TableView.cs

@@ -130,7 +130,7 @@ protected override DependencyObject GetContainerForItemOverride()
         _rows.Add(row);
         return row;
     }
-        
+
     /// <inheritdoc/>
     protected override async void OnKeyDown(KeyRoutedEventArgs e)
     {
@@ -660,7 +660,7 @@ private static TableViewBoundColumn GetTableViewColumnFromType(string? propertyN
         {
             column = new TableViewCheckBoxColumn();
         }
-        else if(type.IsUri())
+        else if (type.IsUri())
         {
             column = new TableViewHyperlinkColumn();
         }
@@ -968,29 +968,20 @@ internal void MakeSelection(TableViewCellSlot slot, bool shiftKey, bool ctrlKey
         {
             ctrlKey = ctrlKey || SelectionMode is ListViewSelectionMode.Multiple;
 
-            if (!ctrlKey || !(SelectionMode is ListViewSelectionMode.Multiple or ListViewSelectionMode.Extended))
-            {
-                if (SelectedItems.Count > 0)
-                {
-                    DeselectAllItems();
-                }
-
-                if (SelectedCells.Count > 0)
-                {
-                    SelectedCellRanges.Clear();
-                }
-            }
-
             if (SelectionUnit is TableViewSelectionUnit.Row
                || (LastSelectionUnit is TableViewSelectionUnit.Row && slot.IsValidRow(this) && !slot.IsValidColumn(this))
                || (SelectionUnit is TableViewSelectionUnit.CellOrRow && slot.IsValidRow(this) && !slot.IsValidColumn(this)))
             {
-                SelectRows(slot, shiftKey);
+                if (!ctrlKey)
+                    DeselectAllCells();
+                SelectRows(slot, shiftKey, ctrlKey);
                 LastSelectionUnit = TableViewSelectionUnit.Row;
             }
             else
             {
-                SelectCells(slot, shiftKey);
+                if (!ctrlKey)
+                    DeselectAllItems();
+                SelectCells(slot, shiftKey, ctrlKey);
                 LastSelectionUnit = TableViewSelectionUnit.Cell;
             }
         }
@@ -1004,34 +995,46 @@ internal void MakeSelection(TableViewCellSlot slot, bool shiftKey, bool ctrlKey
     /// <summary>
     /// Selects rows based on the specified cell slot.
     /// </summary>
-    private void SelectRows(TableViewCellSlot slot, bool shiftKey)
+    private void SelectRows(TableViewCellSlot slot, bool shiftKey, bool ctrlKey)
     {
         var selectionRange = SelectedRanges.FirstOrDefault(x => x.IsInRange(slot.Row));
         SelectionStartRowIndex ??= slot.Row;
-        CurrentRowIndex = slot.Row;
 
-        if (selectionRange is not null)
+        if (selectionRange is not null && ctrlKey && !shiftKey && (CurrentRowIndex != slot.Row || CurrentCellSlot == slot))
         {
-            DeselectRange(selectionRange);
+            DeselectRange(new ItemIndexRange(slot.Row, 1));
         }
-
-        if (shiftKey && SelectionMode is ListViewSelectionMode.Multiple or ListViewSelectionMode.Extended)
+        else if ((!shiftKey && !ctrlKey && SelectedItems.Count <= 1) || SelectionMode is ListViewSelectionMode.Single)
+        {
+            SelectionStartRowIndex = CurrentRowIndex = SelectedIndex = slot.Row;
+        }
+        else if ((!ctrlKey && !shiftKey) || !(SelectionMode is ListViewSelectionMode.Multiple or ListViewSelectionMode.Extended))
+        {
+            SelectionStartRowIndex = CurrentRowIndex = SelectedIndex = slot.Row;
+        }
+        else if (SelectionMode is ListViewSelectionMode.Multiple or ListViewSelectionMode.Extended)
         {
             var min = Math.Min(SelectionStartRowIndex.Value, slot.Row);
             var max = Math.Max(SelectionStartRowIndex.Value, slot.Row);
+            var newSelection = new ItemIndexRange(min, (uint)(max - min) + 1);
 
-            SelectRange(new ItemIndexRange(min, (uint)(max - min) + 1));
-        }
-        else
-        {
-            SelectionStartRowIndex = slot.Row;
-            if (SelectionMode is ListViewSelectionMode.Single)
+            if (!ctrlKey && newSelection.Length == 1)
             {
-                SelectedIndex = slot.Row;
+                SelectionStartRowIndex = CurrentRowIndex = SelectedIndex = slot.Row;
             }
-            else
+            if (selectionRange?.LastIndex > newSelection.LastIndex)
             {
-                SelectRange(new ItemIndexRange(slot.Row, 1));
+                var deselectRange = new ItemIndexRange(newSelection.LastIndex + 1, (uint)(selectionRange.LastIndex - newSelection.LastIndex));
+                DeselectRange(deselectRange);
+            }
+            else if (selectionRange?.FirstIndex < newSelection.FirstIndex)
+            {
+                var deselectRange = new ItemIndexRange(selectionRange.FirstIndex, (uint)(newSelection.FirstIndex - selectionRange.FirstIndex));
+                DeselectRange(deselectRange);
+            }
+            else if (selectionRange != newSelection)
+            {
+                SelectRange(newSelection);
             }
         }
 
@@ -1052,13 +1055,18 @@ private void SelectRows(TableViewCellSlot slot, bool shiftKey)
     /// <summary>
     /// Selects cells based on the specified cell slot.
     /// </summary>
-    private void SelectCells(TableViewCellSlot slot, bool shiftKey)
+    private void SelectCells(TableViewCellSlot slot, bool shiftKey, bool ctrlKey)
     {
         if (!slot.IsValid(this))
         {
             return;
         }
 
+        if (!ctrlKey || !(SelectionMode is ListViewSelectionMode.Multiple or ListViewSelectionMode.Extended))
+        {
+            DeselectAll();
+        }
+
         var selectionRange = (SelectionStartCellSlot is null ? null : SelectedCellRanges.LastOrDefault(x => SelectionStartCellSlot.HasValue && x.Contains(SelectionStartCellSlot.Value))) ?? [];
         SelectedCellRanges.Remove(selectionRange);
         selectionRange.Clear();

src/TableViewCell.cs

@@ -224,7 +224,7 @@ protected override async void OnTapped(TappedRoutedEventArgs e)
             if (e.Handled) return;
         }
 
-        if (TableView?.CurrentCellSlot != Slot)
+        if (TableView?.CurrentCellSlot != Slot || TableView?.LastSelectionUnit is TableViewSelectionUnit.Row)
         {
             MakeSelection();
             e.Handled = true;
@@ -362,7 +362,6 @@ private void MakeSelection()
         }
 
         TableView.SetIsEditing(false);
-        TableView.UpdateCornerButtonState();
     }
 
     /// <summary>