Merge pull request #4505 from AvaloniaUI/expose-cut-copy-paste-textbox

Expose Cut Copy and Paste methods for binding for context menus

src/Avalonia.Controls/TextBox.cs

@@ -18,6 +18,15 @@ namespace Avalonia.Controls
 {
     public class TextBox : TemplatedControl, UndoRedoHelper<TextBox.UndoRedoState>.IUndoRedoHost
     {
+        public static KeyGesture CutGesture { get; } = AvaloniaLocator.Current
+            .GetService<PlatformHotkeyConfiguration>()?.Cut.FirstOrDefault();
+
+        public static KeyGesture CopyGesture { get; } = AvaloniaLocator.Current
+            .GetService<PlatformHotkeyConfiguration>()?.Copy.FirstOrDefault();
+
+        public static KeyGesture PasteGesture { get; } = AvaloniaLocator.Current
+            .GetService<PlatformHotkeyConfiguration>()?.Paste.FirstOrDefault();
+        
         public static readonly StyledProperty<bool> AcceptsReturnProperty =
             AvaloniaProperty.Register<TextBox, bool>(nameof(AcceptsReturn));
 
@@ -103,6 +112,21 @@ namespace Avalonia.Controls
 
         public static readonly StyledProperty<bool> RevealPasswordProperty =
             AvaloniaProperty.Register<TextBox, bool>(nameof(RevealPassword));
+        
+        public static readonly DirectProperty<TextBox, bool> CanCutProperty =
+                    AvaloniaProperty.RegisterDirect<TextBox, bool>(
+                        nameof(CanCut),
+                        o => o.CanCut);
+
+        public static readonly DirectProperty<TextBox, bool> CanCopyProperty =
+            AvaloniaProperty.RegisterDirect<TextBox, bool>(
+                nameof(CanCopy),
+                o => o.CanCopy);
+
+        public static readonly DirectProperty<TextBox, bool> CanPasteProperty =
+                    AvaloniaProperty.RegisterDirect<TextBox, bool>(
+                        nameof(CanPaste),
+                        o => o.CanPaste);
 
         struct UndoRedoState : IEquatable<UndoRedoState>
         {
@@ -126,6 +150,9 @@ namespace Avalonia.Controls
         private UndoRedoHelper<UndoRedoState> _undoRedoHelper;
         private bool _isUndoingRedoing;
         private bool _ignoreTextChanges;
+        private bool _canCut;
+        private bool _canCopy;
+        private bool _canPaste;
         private string _newLine = Environment.NewLine;
         private static readonly string[] invalidCharacters = new String[1] { "\u007f" };
 
@@ -370,6 +397,33 @@ namespace Avalonia.Controls
             set { SetAndRaise(NewLineProperty, ref _newLine, value); }
         }
 
+        /// <summary>
+        /// Property for determining if the Cut command can be executed.
+        /// </summary>
+        public bool CanCut
+        {
+            get { return _canCut; }
+            private set { SetAndRaise(CanCutProperty, ref _canCut, value); }
+        }
+
+        /// <summary>
+        /// Property for determining if the Copy command can be executed.
+        /// </summary>
+        public bool CanCopy
+        {
+            get { return _canCopy; }
+            private set { SetAndRaise(CanCopyProperty, ref _canCopy, value); }
+        }
+
+        /// <summary>
+        /// Property for determining if the Paste command can be executed.
+        /// </summary>
+        public bool CanPaste
+        {
+            get { return _canPaste; }
+            private set { SetAndRaise(CanPasteProperty, ref _canPaste, value); }
+        }
+
         protected override void OnApplyTemplate(TemplateAppliedEventArgs e)
         {
             _presenter = e.NameScope.Get<TextPresenter>("PART_TextPresenter");
@@ -387,9 +441,19 @@ namespace Avalonia.Controls
             if (change.Property == TextProperty)
             {
                 UpdatePseudoclasses();
+                UpdateCommandStates();
             }
         }
 
+        private void UpdateCommandStates()
+        {
+            var text = GetSelection();
+            var b1 = string.IsNullOrEmpty(text);
+            CanCopy = !b1;
+            CanCut = !b1;
+            CanPaste = !IsReadOnly;
+        }
+
         protected override void OnGotFocus(GotFocusEventArgs e)
         {
             base.OnGotFocus(e);
@@ -404,6 +468,8 @@ namespace Avalonia.Controls
                 SelectAll();
             }
 
+            UpdateCommandStates();
+
             _presenter?.ShowCaret();
         }
 
@@ -417,7 +483,9 @@ namespace Avalonia.Controls
                 SelectionEnd = 0;
                 RevealPassword = false;
             }
-            
+
+            UpdateCommandStates();
+
             _presenter?.HideCaret();
         }
 
@@ -460,19 +528,31 @@ namespace Avalonia.Controls
             return text;
         }
 
-        private async void Copy()
+        public async void Cut()
+        {
+            var text = GetSelection();
+            if (text is null) return;
+
+            _undoRedoHelper.Snapshot();
+            Copy();
+            DeleteSelection();
+            _undoRedoHelper.Snapshot();
+        }
+
+        public async void Copy()
         {
+            var text = GetSelection();
+            if (text is null) return;
+
             await ((IClipboard)AvaloniaLocator.Current.GetService(typeof(IClipboard)))
-                .SetTextAsync(GetSelection());
+                .SetTextAsync(text);
         }
 
-        private async void Paste()
+        public async void Paste()
         {
             var text = await ((IClipboard)AvaloniaLocator.Current.GetService(typeof(IClipboard))).GetTextAsync();
-            if (text == null)
-            {
-                return;
-            }
+
+            if (text is null) return;
 
             _undoRedoHelper.Snapshot();
             HandleTextInput(text);
@@ -511,23 +591,18 @@ namespace Avalonia.Controls
             {
                 if (!IsPasswordBox)
                 {
-                    _undoRedoHelper.Snapshot();
-                    Copy();
-                    DeleteSelection();
-                    _undoRedoHelper.Snapshot();
+                    Cut();
                 }
 
                 handled = true;
             }
             else if (Match(keymap.Paste))
             {
-
                 Paste();
                 handled = true;
             }
             else if (Match(keymap.Undo))
             {
-
                 try
                 {
                     _isUndoingRedoing = true;

src/Avalonia.Themes.Default/TextBox.xaml

@@ -1,4 +1,11 @@
 <Styles xmlns="https://github.com/avaloniaui" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+  <Styles.Resources>
+    <ContextMenu x:Key="DefaultTextBoxContextMenu">
+      <MenuItem Header="Cut" Command="{Binding $parent[TextBox].Cut}" IsEnabled="{Binding $parent[TextBox].CanCut}" InputGesture="{x:Static TextBox.CutGesture}" />
+      <MenuItem Header="Copy" Command="{Binding $parent[TextBox].Copy}" IsEnabled="{Binding $parent[TextBox].CanCopy}" InputGesture="{x:Static TextBox.CopyGesture}"/>
+      <MenuItem Header="Paste" Command="{Binding $parent[TextBox].Paste}" IsEnabled="{Binding $parent[TextBox].CanPaste}" InputGesture="{x:Static TextBox.PasteGesture}"/>
+    </ContextMenu>
+  </Styles.Resources>
   <Style Selector="TextBox">
     <Setter Property="Background" Value="{DynamicResource ThemeBackgroundBrush}"/>
     <Setter Property="BorderBrush" Value="{DynamicResource ThemeBorderMidBrush}"/>
@@ -6,6 +13,7 @@
     <Setter Property="SelectionBrush" Value="{DynamicResource HighlightBrush}"/>
     <Setter Property="SelectionForegroundBrush" Value="{DynamicResource HighlightForegroundBrush}"/>
     <Setter Property="Padding" Value="4"/>
+    <Setter Property="ContextMenu" Value="{StaticResource DefaultTextBoxContextMenu}" />
     <Setter Property="Template">
       <ControlTemplate>
         <Border Name="border"

src/Avalonia.Themes.Fluent/TextBox.xaml

@@ -14,6 +14,12 @@
     <StreamGeometry x:Key="TextBoxClearButtonData">M 11.416016,10 20,1.4160156 18.583984,0 10,8.5839846 1.4160156,0 0,1.4160156 8.5839844,10 0,18.583985 1.4160156,20 10,11.416015 18.583984,20 20,18.583985 Z</StreamGeometry>
     <StreamGeometry x:Key="PasswordBoxRevealButtonData">m10.051 7.0032c2.215 0 4.0105 1.7901 4.0105 3.9984s-1.7956 3.9984-4.0105 3.9984c-2.215 0-4.0105-1.7901-4.0105-3.9984s1.7956-3.9984 4.0105-3.9984zm0 1.4994c-1.3844 0-2.5066 1.1188-2.5066 2.499s1.1222 2.499 2.5066 2.499 2.5066-1.1188 2.5066-2.499-1.1222-2.499-2.5066-2.499zm0-5.0026c4.6257 0 8.6188 3.1487 9.7267 7.5613 0.10085 0.40165-0.14399 0.80877-0.54686 0.90931-0.40288 0.10054-0.81122-0.14355-0.91208-0.54521-0.94136-3.7492-4.3361-6.4261-8.2678-6.4261-3.9334 0-7.3292 2.6792-8.2689 6.4306-0.10063 0.40171-0.50884 0.64603-0.91177 0.54571s-0.648-0.5073-0.54737-0.90901c1.106-4.4152 5.1003-7.5667 9.728-7.5667z</StreamGeometry>
     <StreamGeometry x:Key="PasswordBoxHideButtonData">m0.21967 0.21965c-0.26627 0.26627-0.29047 0.68293-0.07262 0.97654l0.07262 0.08412 4.0346 4.0346c-1.922 1.3495-3.3585 3.365-3.9554 5.7495-0.10058 0.4018 0.14362 0.8091 0.54543 0.9097 0.40182 0.1005 0.80909-0.1436 0.90968-0.5455 0.52947-2.1151 1.8371-3.8891 3.5802-5.0341l1.8096 1.8098c-0.70751 0.7215-1.1438 1.71-1.1438 2.8003 0 2.2092 1.7909 4 4 4 1.0904 0 2.0788-0.4363 2.8004-1.1438l5.9193 5.9195c0.2929 0.2929 0.7677 0.2929 1.0606 0 0.2663-0.2662 0.2905-0.6829 0.0726-0.9765l-0.0726-0.0841-6.1135-6.1142 0.0012-0.0015-1.2001-1.1979-2.8699-2.8693 2e-3 -8e-4 -2.8812-2.8782 0.0012-0.0018-1.1333-1.1305-4.3064-4.3058c-0.29289-0.29289-0.76777-0.29289-1.0607 0zm7.9844 9.0458 3.5351 3.5351c-0.45 0.4358-1.0633 0.704-1.7392 0.704-1.3807 0-2.5-1.1193-2.5-2.5 0-0.6759 0.26824-1.2892 0.7041-1.7391zm1.7959-5.7655c-1.0003 0-1.9709 0.14807-2.8889 0.425l1.237 1.2362c0.5358-0.10587 1.0883-0.16119 1.6519-0.16119 3.9231 0 7.3099 2.6803 8.2471 6.4332 0.1004 0.4018 0.5075 0.6462 0.9094 0.5459 0.4019-0.1004 0.6463-0.5075 0.5459-0.9094-1.103-4.417-5.0869-7.5697-9.7024-7.5697zm0.1947 3.5093 3.8013 3.8007c-0.1018-2.0569-1.7488-3.7024-3.8013-3.8007z</StreamGeometry>
+    
+    <ContextMenu x:Key="DefaultTextBoxContextMenu">
+      <MenuItem Header="Cut" Command="{Binding $parent[TextBox].Cut}" IsEnabled="{Binding $parent[TextBox].CanCut}" InputGesture="{x:Static TextBox.CutGesture}" />
+      <MenuItem Header="Copy" Command="{Binding $parent[TextBox].Copy}" IsEnabled="{Binding $parent[TextBox].CanCopy}" InputGesture="{x:Static TextBox.CopyGesture}"/>
+      <MenuItem Header="Paste" Command="{Binding $parent[TextBox].Paste}" IsEnabled="{Binding $parent[TextBox].CanPaste}" InputGesture="{x:Static TextBox.PasteGesture}"/>
+    </ContextMenu>
   </Styles.Resources>
 
   <Style Selector="TextBox">
@@ -28,6 +34,7 @@
     <Setter Property="MinWidth" Value="{DynamicResource TextControlThemeMinWidth}" />
     <Setter Property="Padding" Value="{DynamicResource TextControlThemePadding}" />
     <Setter Property="FocusAdorner" Value="{x:Null}" />
+    <Setter Property="ContextMenu" Value="{StaticResource DefaultTextBoxContextMenu}" />
     <Setter Property="Template">
       <ControlTemplate>
         <DockPanel>