Added failing test for #507.

tests/Avalonia.Markup.Xaml.UnitTests/Xaml/ControlBindingTests.cs

@@ -1,7 +1,10 @@
 // Copyright (c) The Avalonia Project. All rights reserved.
 // Licensed under the MIT license. See licence.md file in the project root for full license information.
 
+using System.Collections.Generic;
 using Avalonia.Controls;
+using Avalonia.Controls.Primitives;
+using Avalonia.Layout;
 using Avalonia.Logging;
 using Avalonia.UnitTests;
 using Xunit;
@@ -67,5 +70,61 @@ namespace Avalonia.Markup.Xaml.UnitTests.Xaml
                 Assert.True(called);
             }
         }
+
+        [Fact]
+        public void Can_Bind_Between_TabStrip_And_Carousel()
+        {
+            using (UnitTestApplication.Start(TestServices.StyledWindow))
+            {
+                var xaml = @"
+<Window xmlns='https://github.com/avaloniaui'>
+    <DockPanel>
+        <TabStrip Name='strip' DockPanel.Dock='Top' Items='{Binding Items}' SelectedIndex='0'>
+          <TabStrip.DataTemplates>
+            <DataTemplate>
+              <TextBlock Text='{Binding Header}'/>
+            </DataTemplate>
+          </TabStrip.DataTemplates>
+        </TabStrip>
+        <Carousel Name='carousel' Items='{Binding Items}' SelectedIndex='{Binding #strip.SelectedIndex}'>
+          <Carousel.DataTemplates>
+            <DataTemplate>
+              <TextBlock Text='{Binding Detail}'/>
+            </DataTemplate>
+          </Carousel.DataTemplates>
+        </Carousel>
+    </DockPanel>
+</Window>";
+                var loader = new AvaloniaXamlLoader();
+                var window = (Window)loader.Load(xaml);
+                var strip = window.FindControl<TabStrip>("strip");
+                var carousel = window.FindControl<Carousel>("carousel");
+
+                window.DataContext = new ItemsViewModel
+                {
+                    Items = new[]
+                    {
+                        new ItemViewModel { Header = "Item1", Detail = "Detail1" },
+                        new ItemViewModel { Header = "Item2", Detail = "Detail2" },
+                    }
+                };
+
+                window.Show();
+
+                Assert.Equal(0, strip.SelectedIndex);
+                Assert.Equal(0, carousel.SelectedIndex);
+            }
+        }
+
+        private class ItemsViewModel
+        {
+            public IList<ItemViewModel> Items { get; set; }
+        }
+
+        private class ItemViewModel
+        {
+            public string Header { get; set; }
+            public string Detail { get; set; }
+        }
     }
 }