implemented auto resizing column by double clicking on resize area

Author: w-ahmad

src/WinUI.TableView/TableViewCell.cs

@@ -1,12 +1,12 @@
-using CommunityToolkit.WinUI;
-using Microsoft.UI.Input;
+using Microsoft.UI.Input;
 using Microsoft.UI.Xaml;
 using Microsoft.UI.Xaml.Controls;
 using Microsoft.UI.Xaml.Input;
 using Microsoft.UI.Xaml.Media;
 using System;
 using System.Linq;
 using System.Threading.Tasks;
+using Windows.Foundation;
 using Windows.System;
 using Windows.UI.Core;
 
@@ -22,6 +22,13 @@ public TableViewCell()
         DefaultStyleKey = typeof(TableViewCell);
     }
 
+    protected override Size MeasureOverride(Size availableSize)
+    {
+        var size = base.MeasureOverride(availableSize);
+        Column.DesiredWidth = Math.Max(Column.DesiredWidth, size.Width);
+        return size;
+    }
+
     protected override void OnDoubleTapped(DoubleTappedRoutedEventArgs e)
     {
         if (!IsReadOnly)

src/WinUI.TableView/TableViewColumn.cs

@@ -72,6 +72,8 @@ private void EnsureHeaderStyle()
         }
     }
 
+    internal double DesiredWidth { get; set; }
+
     public static readonly DependencyProperty HeaderStyleProperty = DependencyProperty.Register(nameof(HeaderStyle), typeof(Style), typeof(TableViewColumn), new PropertyMetadata(null, (d, _) => ((TableViewColumn)d).EnsureHeaderStyle()));
     public static readonly DependencyProperty HeaderProperty = DependencyProperty.Register(nameof(Header), typeof(object), typeof(TableViewColumn), new PropertyMetadata(null));
     public static readonly DependencyProperty WidthProperty = DependencyProperty.Register(nameof(Width), typeof(double), typeof(TableViewColumn), new PropertyMetadata(200d));

src/WinUI.TableView/TableViewColumnHeader.cs

@@ -307,6 +307,29 @@ private bool IsCursorInLeftResizeArea(PointerRoutedEventArgs args)
         return point.Position.X <= resizeArea && point.Position.Y < ActualHeight;
     }
 
+    protected override void OnDoubleTapped(DoubleTappedRoutedEventArgs e)
+    {
+        base.OnDoubleTapped(e);
+
+        if (IsSizingCursor && Column is not null)
+        {
+            var position = e.GetPosition(this);
+
+            if (position.X <= 8 && _headerRow?.GetPreviousHeader(this) is { Column: { } } header)
+            {
+                var width = Math.Clamp(header.Column.DesiredWidth, header.MinWidth, header.MaxWidth);
+                header.Width = width;
+                header.Measure(new Size(Width, ActualHeight));
+            }
+            else
+            {
+                var width = Math.Clamp(Column.DesiredWidth, MinWidth, MaxWidth);
+                Width = width;
+                Measure(new Size(Width, ActualHeight));
+            }
+        }
+    }
+
     protected override void OnPointerMoved(PointerRoutedEventArgs e)
     {
         base.OnPointerMoved(e);