Merge pull request #4498 from AvaloniaUI/fixes/dont-loose-textselection-when-context-menu-opens

TextBox - dont lose textselection when context menu opens

src/Avalonia.Controls/ContextMenu.cs

@@ -280,9 +280,8 @@ namespace Avalonia.Controls
             }
 
             _popup.Child = this;
-            _popup.IsOpen = true;
-
             IsOpen = true;
+            _popup.IsOpen = true;
 
             RaiseEvent(new RoutedEventArgs
             {

src/Avalonia.Controls/TextBox.cs

@@ -410,10 +410,15 @@ namespace Avalonia.Controls
         protected override void OnLostFocus(RoutedEventArgs e)
         {
             base.OnLostFocus(e);
-            SelectionStart = 0;
+
-            SelectionEnd = 0;
+            if (ContextMenu == null || !ContextMenu.IsOpen)
+            {
+                SelectionStart = 0;
+                SelectionEnd = 0;
+                RevealPassword = false;
+            }
+            
             _presenter?.HideCaret();
-            RevealPassword = false;
         }
 
         protected override void OnTextInput(TextInputEventArgs e)

tests/Avalonia.Controls.UnitTests/TextBoxTests.cs

@@ -17,6 +17,46 @@ namespace Avalonia.Controls.UnitTests
 {
     public class TextBoxTests
     {
+        [Fact]
+        public void Opening_Context_Menu_Does_not_Lose_Selection()
+        {
+            using (UnitTestApplication.Start(FocusServices))
+            {
+                var target1 = new TextBox
+                {
+                    Template = CreateTemplate(),
+                    Text = "1234",
+                    ContextMenu = new TestContextMenu()
+                };
+
+                var target2 = new TextBox
+                {
+                    Template = CreateTemplate(),
+                    Text = "5678"
+                };
+                
+                var sp = new StackPanel();
+                sp.Children.Add(target1);
+                sp.Children.Add(target2);
+
+                target1.ApplyTemplate();
+                target2.ApplyTemplate();
+                
+                var root = new TestRoot() { Child = sp };
+
+                target1.SelectionStart = 0;
+                target1.SelectionEnd = 3;
+                
+                target1.Focus();
+                Assert.False(target2.IsFocused);
+                Assert.True(target1.IsFocused);
+
+                target2.Focus();
+                
+                Assert.Equal("123", target1.SelectedText);
+            }
+        }
+        
         [Fact]
         public void DefaultBindingMode_Should_Be_TwoWay()
         {
@@ -694,5 +734,13 @@ namespace Avalonia.Controls.UnitTests
 
             public Task<object> GetDataAsync(string format) => Task.FromResult((object)null);
         }
+        
+        private class TestContextMenu : ContextMenu
+        {
+            public TestContextMenu()
+            {
+                IsOpen = true;
+            }
+        }
     }
 }