Use Ctrl+click for additive DataGrid sorting

Author: xoofx

samples/ControlsDemo/Demos/DataGridDemo.cs

@@ -68,7 +68,7 @@ public override Visual Build(DemoContext context)
 
         return new VStack(
                 DemoUi.Hint("Wrap DataGridControl in a ScrollViewer to show scrollbars."),
-                DemoUi.Hint("Click a header sort button to cycle off/descending/ascending. Shift+click adds a secondary sort."),
+                DemoUi.Hint("Click a header sort button to cycle off/descending/ascending. Ctrl+click adds a secondary sort."),
                 DemoUi.Hint("Ctrl+F: search (find), F3/Shift+F3: next/previous match"),
                 DemoUi.Hint("F4: toggle filter row, F2: edit current cell"),
                 controls,

site/docs/controls/datagrid.md

@@ -105,7 +105,7 @@ Sorting is opt-in per UI column:
 - set `DataGridColumn.Sortable = true` to show the header sort button,
 - optionally set `DataGridColumn<T>.SortComparer` to override the default `Comparer<T>.Default`,
 - click the header sort button to cycle `None -> Descending -> Ascending -> None`,
-- `Shift+click` adds/removes secondary sorts so multi-column sorts are additive and stable.
+- `Ctrl+click` adds/removes secondary sorts so multi-column sorts are additive and stable (`Alt+click` is also accepted).
 
 You can also sort programmatically:
 
@@ -121,7 +121,7 @@ When the view is a `DataGridDocumentView`, any configured `SortComparer` is forw
 - `Ctrl+F`: open find UI (uses `SearchReplacePopup` in find mode)
 - `F3` / `Shift+F3`: next / previous match
 - `F4`: toggle filter row (when `View` is filterable)
-- click header sort button: toggle sort (`Shift+click` for additive multi-sort)
+- click header sort button: toggle sort (`Ctrl+click` for additive multi-sort; `Alt+click` also works)
 - Arrow keys / PageUp / PageDown: navigate the current cell
 - `F2` or `Enter`: edit current cell (when editable)
 

site/docs/specs/controls/datagrid.md

@@ -704,7 +704,7 @@ Suggested UX:
 
 - sortable columns render a sort button in the header (right aligned inside the header cell)
 - click the sort button toggles `None → Desc → Asc → None`
-- `Shift+click` adds/removes secondary sort (multi-sort)
+- `Ctrl+click` adds/removes secondary sort (multi-sort); `Alt+click` MAY be accepted as an equivalent terminal-safe modifier
 - programmatic sorting is available through `DataGridControl.TrySetColumnSortDirection(...)`
 - the default `DataGridDocumentView` preserves row stability by using the full active sort description list and falling
   back to document order for ties

src/XenoAtom.Terminal.UI.Tests/DataGridSortingTests.cs

@@ -149,6 +149,54 @@ static string GetRenderedText(TerminalAppTestDriver currentDriver)
         Assert.AreEqual("a", ((SortRow)view.CurrentSnapshot.GetRowModel(0)).Name);
     }
 
+    [TestMethod]
+    public void DataGrid_Header_Sort_Button_Uses_Ctrl_Click_For_Additive_Sort()
+    {
+        var groupAccessor = new BindingAccessor<string>("group", o => ((GroupedSortRow)o).Group, (o, v) => ((GroupedSortRow)o).Group = v);
+        var nameAccessor = new BindingAccessor<string>("name", o => ((GroupedSortRow)o).Name, (o, v) => ((GroupedSortRow)o).Name = v);
+
+        var doc = new DataGridListDocument<GroupedSortRow>();
+        doc.SetColumns(new[]
+        {
+            new DataGridColumnInfo("group", "Group", typeof(string), ReadOnly: false, groupAccessor),
+            new DataGridColumnInfo("name", "Name", typeof(string), ReadOnly: false, nameAccessor),
+        });
+
+        doc.AddRow(new GroupedSortRow { Group = "B", Name = "a", Sequence = 0 });
+        doc.AddRow(new GroupedSortRow { Group = "A", Name = "b", Sequence = 1 });
+        doc.AddRow(new GroupedSortRow { Group = "A", Name = "a", Sequence = 2 });
+
+        using var view = new DataGridDocumentView(doc);
+
+        var grid = new DataGridControl { View = view, ShowRowAnchor = false };
+        grid.Columns.Add(new DataGridColumn<string> { Key = "group", TypedValueAccessor = groupAccessor, Width = GridLength.Fixed(7), Sortable = true });
+        grid.Columns.Add(new DataGridColumn<string> { Key = "name", TypedValueAccessor = nameAccessor, Width = GridLength.Fixed(6), Sortable = true });
+
+        using var driver = new TerminalAppTestDriver(grid, TerminalHostKind.Fullscreen, new TerminalSize(16, 5));
+        driver.Tick();
+
+        var groupSortButtonX = grid.Bounds.X + 6;
+        var nameSortButtonX = grid.Bounds.X + 13;
+        var sortButtonY = grid.Bounds.Y;
+
+        driver.Backend.PushEvent(new TerminalMouseEvent { Kind = TerminalMouseKind.Down, Button = TerminalMouseButton.Left, X = groupSortButtonX, Y = sortButtonY });
+        driver.Backend.PushEvent(new TerminalMouseEvent { Kind = TerminalMouseKind.Up, Button = TerminalMouseButton.Left, X = groupSortButtonX, Y = sortButtonY });
+        driver.Tick();
+
+        driver.Backend.PushEvent(new TerminalMouseEvent { Kind = TerminalMouseKind.Down, Button = TerminalMouseButton.Left, X = nameSortButtonX, Y = sortButtonY, Modifiers = TerminalModifiers.Ctrl });
+        driver.Backend.PushEvent(new TerminalMouseEvent { Kind = TerminalMouseKind.Up, Button = TerminalMouseButton.Left, X = nameSortButtonX, Y = sortButtonY, Modifiers = TerminalModifiers.Ctrl });
+        driver.Tick();
+
+        var sorts = grid.SortDescriptions.ToArray();
+        CollectionAssert.AreEqual(
+            new[]
+            {
+                new DataGridSortDescription("group", DataGridSortDirection.Descending),
+                new DataGridSortDescription("name", DataGridSortDirection.Descending),
+            },
+            sorts);
+    }
+
     private sealed class SortRow
     {
         public string Name { get; set; } = string.Empty;

src/XenoAtom.Terminal.UI/Controls/DataGridControl.cs

@@ -1377,7 +1377,7 @@ protected override void OnPointerReleased(PointerEventArgs e)
                 var columns = EnsureResolvedColumns(snapshot, visibleColumns);
                 if ((uint)sortColumnIndex < (uint)columns.Count)
                 {
-                    _ = TryToggleColumnSortDirection(columns[sortColumnIndex].Key, additive: (e.Modifiers & TerminalModifiers.Shift) != 0);
+                    _ = TryToggleColumnSortDirection(columns[sortColumnIndex].Key, additive: IsAdditiveSortModifier(e.Modifiers));
                 }
             }
 
@@ -1809,6 +1809,9 @@ private void ConfigureSortComparers()
 
     private bool CanSort => View is ISortableDataGridView;
 
+    private static bool IsAdditiveSortModifier(TerminalModifiers modifiers)
+        => (modifiers & (TerminalModifiers.Ctrl | TerminalModifiers.Alt)) != 0;
+
     private bool TryGetSortableColumn(string columnKey, out DataGridColumn? column)
     {
         for (var i = 0; i < Columns.Count; i++)