Merge pull request #2654 from Abdulbaqi-Alshareef/SelectionBrushFeature

Add SelectionBrush and SelectionForegroundBrush feature to TextBox

samples/ControlCatalog/Pages/TextBoxPage.xaml

@@ -26,6 +26,9 @@
         <TextBox Width="200" Text="Left aligned text" TextAlignment="Left" />
         <TextBox Width="200" Text="Center aligned text" TextAlignment="Center" />
         <TextBox Width="200" Text="Right aligned text" TextAlignment="Right" />
+        <TextBox Width="200" Text="Custom selection brush"
+                  SelectionStart="5" SelectionEnd="22"
+                  SelectionBrush="Green" SelectionForegroundBrush="Yellow"/>
         <TextBox Width="200" Text="Custom caret brush" CaretBrush="DarkOrange"/>
       </StackPanel>
 

src/Avalonia.Controls/Presenters/TextPresenter.cs

@@ -19,6 +19,12 @@ namespace Avalonia.Controls.Presenters
         public static readonly StyledProperty<char> PasswordCharProperty =
             AvaloniaProperty.Register<TextPresenter, char>(nameof(PasswordChar));
 
+        public static readonly StyledProperty<IBrush> SelectionBrushProperty =
+            AvaloniaProperty.Register<TextPresenter, IBrush>(nameof(SelectionBrushProperty));
+
+        public static readonly StyledProperty<IBrush> SelectionForegroundBrushProperty =
+            AvaloniaProperty.Register<TextPresenter, IBrush>(nameof(SelectionForegroundBrushProperty));
+
         public static readonly StyledProperty<IBrush> CaretBrushProperty =
             AvaloniaProperty.Register<TextPresenter, IBrush>(nameof(CaretBrushProperty));
 
@@ -37,7 +43,6 @@ namespace Avalonia.Controls.Presenters
         private int _selectionStart;
         private int _selectionEnd;
         private bool _caretBlink;
-        private IBrush _highlightBrush;
 
         static TextPresenter()
         {
@@ -82,6 +87,18 @@ namespace Avalonia.Controls.Presenters
             set => SetValue(PasswordCharProperty, value);
         }
 
+        public IBrush SelectionBrush
+        {
+            get => GetValue(SelectionBrushProperty);
+            set => SetValue(SelectionBrushProperty, value);
+        }
+
+        public IBrush SelectionForegroundBrush
+        {
+            get => GetValue(SelectionForegroundBrushProperty);
+            set => SetValue(SelectionForegroundBrushProperty, value);
+        }
+        
         public IBrush CaretBrush
         {
             get => GetValue(CaretBrushProperty);
@@ -138,14 +155,9 @@ namespace Avalonia.Controls.Presenters
 
                 var rects = FormattedText.HitTestTextRange(start, length);
 
-                if (_highlightBrush == null)
-                {
-                    _highlightBrush = (IBrush)this.FindResource("HighlightBrush");
-                }
-
                 foreach (var rect in rects)
                 {
-                    context.FillRectangle(_highlightBrush, rect);
+                    context.FillRectangle(SelectionBrush, rect);
                 }
             }
 
@@ -266,7 +278,7 @@ namespace Avalonia.Controls.Presenters
             {
                 result.Spans = new[]
                 {
-                    new FormattedTextStyleSpan(start, length, foregroundBrush: Brushes.White),
+                    new FormattedTextStyleSpan(start, length, SelectionForegroundBrush),
                 };
             }
 

src/Avalonia.Controls/TextBox.cs

@@ -38,8 +38,14 @@ namespace Avalonia.Controls
         public static readonly StyledProperty<char> PasswordCharProperty =
             AvaloniaProperty.Register<TextBox, char>(nameof(PasswordChar));
 
+        public static readonly StyledProperty<IBrush> SelectionBrushProperty =
+            AvaloniaProperty.Register<TextBox, IBrush>(nameof(SelectionBrushProperty));
+
+        public static readonly StyledProperty<IBrush> SelectionForegroundBrushProperty =
+            AvaloniaProperty.Register<TextBox, IBrush>(nameof(SelectionForegroundBrushProperty));
+
         public static readonly StyledProperty<IBrush> CaretBrushProperty =
-            AvaloniaProperty.Register<TextPresenter, IBrush>(nameof(CaretBrushProperty));
+            AvaloniaProperty.Register<TextBox, IBrush>(nameof(CaretBrushProperty));
 
         public static readonly DirectProperty<TextBox, int> SelectionStartProperty =
             AvaloniaProperty.RegisterDirect<TextBox, int>(
@@ -172,6 +178,18 @@ namespace Avalonia.Controls
             set => SetValue(PasswordCharProperty, value);
         }
 
+        public IBrush SelectionBrush
+        {
+            get => GetValue(SelectionBrushProperty);
+            set => SetValue(SelectionBrushProperty, value);
+        }
+
+        public IBrush SelectionForegroundBrush
+        {
+            get => GetValue(SelectionForegroundBrushProperty);
+            set => SetValue(SelectionForegroundBrushProperty, value);
+        }
+
         public IBrush CaretBrush
         {
             get => GetValue(CaretBrushProperty);
@@ -465,7 +483,7 @@ namespace Avalonia.Controls
                 movement = true;
                 selection = false;
                 handled = true;
-                
+
             }
             else if (Match(keymap.MoveCursorToTheEndOfLine))
             {
@@ -494,7 +512,7 @@ namespace Avalonia.Controls
                 movement = true;
                 selection = true;
                 handled = true;
-                
+
             }
             else if (Match(keymap.MoveCursorToTheEndOfLineWithSelection))
             {

src/Avalonia.Themes.Default/Accents/BaseDark.xaml

@@ -22,6 +22,7 @@
         <Color x:Key="ThemeForegroundLowColor">#FF808080</Color>
 
         <Color x:Key="HighlightColor">#FF119EDA</Color>
+        <Color x:Key="HighlightForegroundColor">#FFFFFFFF</Color>
         <Color x:Key="ErrorColor">#FFFF0000</Color>
         <Color x:Key="ErrorLowColor">#10FF0000</Color>
 
@@ -39,6 +40,7 @@
         <SolidColorBrush x:Key="ThemeForegroundLowBrush" Color="{DynamicResource ThemeForegroundLowColor}"></SolidColorBrush>
 
         <SolidColorBrush x:Key="HighlightBrush" Color="{DynamicResource HighlightColor}"></SolidColorBrush>
+        <SolidColorBrush x:Key="HighlightForegroundBrush" Color="{DynamicResource HighlightForegroundColor}"></SolidColorBrush>
         <SolidColorBrush x:Key="ThemeAccentBrush" Color="{DynamicResource ThemeAccentColor}"></SolidColorBrush>
         <SolidColorBrush x:Key="ThemeAccentBrush2" Color="{DynamicResource ThemeAccentColor2}"></SolidColorBrush>
         <SolidColorBrush x:Key="ThemeAccentBrush3" Color="{DynamicResource ThemeAccentColor3}"></SolidColorBrush>

src/Avalonia.Themes.Default/Accents/BaseLight.xaml

@@ -22,6 +22,7 @@
         <Color x:Key="ThemeForegroundLowColor">#FF808080</Color>
 
         <Color x:Key="HighlightColor">#FF086F9E</Color>
+        <Color x:Key="HighlightForegroundColor">#FFFFFFFF</Color>
         <Color x:Key="ErrorColor">#FFFF0000</Color>
         <Color x:Key="ErrorLowColor">#10FF0000</Color>
 
@@ -39,6 +40,7 @@
         <SolidColorBrush x:Key="ThemeForegroundLowBrush" Color="{DynamicResource ThemeForegroundLowColor}"></SolidColorBrush>
 
         <SolidColorBrush x:Key="HighlightBrush" Color="{DynamicResource HighlightColor}"></SolidColorBrush>
+        <SolidColorBrush x:Key="HighlightForegroundBrush" Color="{DynamicResource HighlightForegroundColor}"></SolidColorBrush>
         <SolidColorBrush x:Key="ThemeAccentBrush" Color="{DynamicResource ThemeAccentColor}"></SolidColorBrush>
         <SolidColorBrush x:Key="ThemeAccentBrush2" Color="{DynamicResource ThemeAccentColor2}"></SolidColorBrush>
         <SolidColorBrush x:Key="ThemeAccentBrush3" Color="{DynamicResource ThemeAccentColor3}"></SolidColorBrush>

src/Avalonia.Themes.Default/TextBox.xaml

@@ -3,6 +3,8 @@
     <Setter Property="Background" Value="{DynamicResource ThemeBackgroundBrush}"/>
     <Setter Property="BorderBrush" Value="{DynamicResource ThemeBorderMidBrush}"/>
     <Setter Property="BorderThickness" Value="{DynamicResource ThemeBorderThickness}"/>
+    <Setter Property="SelectionBrush" Value="{DynamicResource HighlightBrush}"/>
+    <Setter Property="SelectionForegroundBrush" Value="{DynamicResource HighlightForegroundBrush}"/>
     <Setter Property="Padding" Value="4"/>
     <Setter Property="Template">
       <ControlTemplate>
@@ -45,6 +47,8 @@
                                  TextAlignment="{TemplateBinding TextAlignment}"
                                  TextWrapping="{TemplateBinding TextWrapping}"
                                  PasswordChar="{TemplateBinding PasswordChar}"
+                                 SelectionBrush="{TemplateBinding SelectionBrush}"
+                                 SelectionForegroundBrush="{TemplateBinding SelectionForegroundBrush}"
                                  CaretBrush="{TemplateBinding CaretBrush}"/>
                 </Panel>
               </ScrollViewer>