Add TabItem HeaderDisplayMemberBinding

src/Avalonia.Controls/Generators/TabItemContainerGenerator.cs

@@ -2,6 +2,7 @@ using System;
 using System.Collections.Generic;
 using Avalonia.Controls.Primitives;
 using Avalonia.Controls.Templates;
+using Avalonia.Data;
 using Avalonia.LogicalTree;
 using Avalonia.Reactive;
 using Avalonia.VisualTree;
@@ -33,6 +34,12 @@ namespace Avalonia.Controls.Generators
                     TabControl.ItemTemplateProperty));
             }
 
+            if (Owner.HeaderDisplayMemberBinding is not null)
+            {
+                tabItem.Bind(HeaderedContentControl.HeaderProperty, Owner.HeaderDisplayMemberBinding,
+                    BindingPriority.Style);
+            }
+
             if (tabItem.Header == null)
             {
                 if (item is IHeadered headered)

src/Avalonia.Controls/TabControl.cs

@@ -12,6 +12,7 @@ using Avalonia.LogicalTree;
 using Avalonia.VisualTree;
 using Avalonia.Automation;
 using Avalonia.Controls.Metadata;
+using Avalonia.Data;
 
 namespace Avalonia.Controls
 {
@@ -57,6 +58,12 @@ namespace Avalonia.Controls
         public static readonly StyledProperty<IDataTemplate?> SelectedContentTemplateProperty =
             AvaloniaProperty.Register<TabControl, IDataTemplate?>(nameof(SelectedContentTemplate));
 
+        /// <summary>
+        /// Defines the <see cref="HeaderDisplayMemberBinding" /> property
+        /// </summary>
+        public static readonly StyledProperty<IBinding?> HeaderDisplayMemberBindingProperty =
+            AvaloniaProperty.Register<HeaderedItemsControl, IBinding?>(nameof(HeaderDisplayMemberBinding));
+        
         /// <summary>
         /// The default value for the <see cref="ItemsControl.ItemsPanel"/> property.
         /// </summary>
@@ -134,6 +141,16 @@ namespace Avalonia.Controls
             get { return GetValue(SelectedContentTemplateProperty); }
             internal set { SetValue(SelectedContentTemplateProperty, value); }
         }
+        
+        /// <summary>
+        /// Gets or sets the <see cref="IBinding"/> to use for binding to the display member of each tab-items header.
+        /// </summary>
+        [AssignBinding]
+        public IBinding? HeaderDisplayMemberBinding
+        {
+            get { return GetValue(HeaderDisplayMemberBindingProperty); }
+            set { SetValue(HeaderDisplayMemberBindingProperty, value); }
+        }
 
         internal ItemsPresenter? ItemsPresenterPart { get; private set; }