Merge pull request #9245 from Gillibald/feature/txtBlockInlines

Move inlines support to TextBlock and rename RichTextBlock

samples/ControlCatalog/Pages/TextBlockPage.xaml

@@ -118,7 +118,7 @@
         </StackPanel>
       </Border>
       <Border>
-        <RichTextBlock SelectionBrush="LightBlue" IsTextSelectionEnabled="True" Margin="10" TextWrapping="Wrap">
+        <SelectableTextBlock SelectionBrush="LightBlue" Margin="10" TextWrapping="Wrap">
           This <Span FontWeight="Bold">is</Span> a
           <Span Background="Silver" Foreground="Maroon">TextBlock</Span>
           with <Span TextDecorations="Underline">several</Span>
@@ -126,7 +126,7 @@
           <Span Foreground="Blue">
             using a <Bold>variety</Bold> of <Italic>styles</Italic>
           </Span>.
-        </RichTextBlock>
+        </SelectableTextBlock>
       </Border>
     </WrapPanel>
   </StackPanel>

src/Avalonia.Base/Media/TextFormatting/TextFormatterImpl.cs

@@ -505,7 +505,7 @@ namespace Avalonia.Media.TextFormatting
 
                     case { } drawableTextRun:
                         {
-                            if (currentWidth + drawableTextRun.Size.Width > paragraphWidth)
+                            if (currentWidth + drawableTextRun.Size.Width >= paragraphWidth)
                             {
                                 goto found;
                             }
@@ -668,7 +668,7 @@ namespace Avalonia.Media.TextFormatting
 
                 if (!breakFound)
                 {
-                    currentLength += currentRun.Text.Length;
+                    currentLength += currentRun.TextSourceLength;
 
                     continue;
                 }

src/Avalonia.Controls/Documents/InlineCollection.cs

@@ -12,7 +12,7 @@ namespace Avalonia.Controls.Documents
     [WhitespaceSignificantCollection]
     public class InlineCollection : AvaloniaList<Inline>
     {
-        private ILogical? _parent;
+        private IAvaloniaList<ILogical>? _logicalChildren;
         private IInlineHost? _inlineHost;
 
         /// <summary>
@@ -24,28 +24,30 @@ namespace Avalonia.Controls.Documents
 
             this.ForEachItem(
                 x =>
-                {
+                {                   
-                    ((ISetLogicalParent)x).SetParent(Parent);
                     x.InlineHost = InlineHost;
+                    LogicalChildren?.Add(x);
                     Invalidate();
                 },
                 x =>
                 {
-                    ((ISetLogicalParent)x).SetParent(null);
+                    LogicalChildren?.Remove(x);
                     x.InlineHost = InlineHost;
                     Invalidate();
                 },
                 () => throw new NotSupportedException());
         }
 
-        internal ILogical? Parent
+        internal IAvaloniaList<ILogical>? LogicalChildren
         {
-            get => _parent;
+            get => _logicalChildren;
             set
             {
-                _parent = value;
+                var oldValue = _logicalChildren;
+
+                _logicalChildren = value;
 
-                OnParentChanged(value);
+                OnParentChanged(oldValue, value);
             }
         }
 
@@ -70,6 +72,11 @@ namespace Avalonia.Controls.Documents
         {
             get
             {
+                if (Count == 0)
+                {
+                    return null;
+                }
+
                 var builder = StringBuilderCache.Acquire();
 
                 foreach (var inline in this)
@@ -111,7 +118,7 @@ namespace Avalonia.Controls.Documents
 
         private void AddText(string text)
         {
-            if (Parent is RichTextBlock textBlock && !textBlock.HasComplexContent)
+            if (LogicalChildren is TextBlock textBlock && !textBlock.HasComplexContent)
             {
                 textBlock._text += text;
             }
@@ -123,7 +130,7 @@ namespace Avalonia.Controls.Documents
 
         private void OnAdd()
         {
-            if (Parent is RichTextBlock textBlock)
+            if (LogicalChildren is TextBlock textBlock)
             {
                 if (!textBlock.HasComplexContent && !string.IsNullOrEmpty(textBlock._text))
                 {
@@ -152,20 +159,21 @@ namespace Avalonia.Controls.Documents
             Invalidated?.Invoke(this, EventArgs.Empty);
         }
 
-        private void OnParentChanged(ILogical? parent)
+        private void OnParentChanged(IAvaloniaList<ILogical>? oldParent, IAvaloniaList<ILogical>? newParent)
         {
             foreach (var child in this)
             {
-                var oldParent = child.Parent;
+                if (oldParent != newParent)
-
-                if (oldParent != parent)
                 {
                     if (oldParent != null)
                     {
-                        ((ISetLogicalParent)child).SetParent(null);
+                        oldParent.Remove(child);
                     }
 
-                    ((ISetLogicalParent)child).SetParent(parent);
+                    if(newParent != null)
+                    {
+                        newParent.Add(child);
+                    }
                 }
             }
         }

src/Avalonia.Controls/Documents/Span.cs

@@ -21,7 +21,7 @@ namespace Avalonia.Controls.Documents
         {
             Inlines = new InlineCollection
             {
-                Parent = this
+                LogicalChildren = LogicalChildren
             };
         }
 
@@ -78,14 +78,14 @@ namespace Avalonia.Controls.Documents
         {
             if (oldValue is not null)
             {
-                oldValue.Parent = null;
+                oldValue.LogicalChildren = null;
                 oldValue.InlineHost = null;
                 oldValue.Invalidated -= (s, e) => InlineHost?.Invalidate();
             }
 
             if (newValue is not null)
             {
-                newValue.Parent = this;
+                newValue.LogicalChildren = LogicalChildren;
                 newValue.InlineHost = InlineHost;
                 newValue.Invalidated += (s, e) => InlineHost?.Invalidate();
             }

src/Avalonia.Controls/RichTextBlock.cs → src/Avalonia.Controls/SelectableTextBlock.cs

@@ -8,7 +8,6 @@ using Avalonia.Input.Platform;
 using Avalonia.Interactivity;
 using Avalonia.Media;
 using Avalonia.Media.TextFormatting;
-using Avalonia.Metadata;
 using Avalonia.Utilities;
 
 namespace Avalonia.Controls
@@ -16,67 +15,53 @@ namespace Avalonia.Controls
     /// <summary>
     /// A control that displays a block of formatted text.
     /// </summary>
-    public class RichTextBlock : TextBlock, IInlineHost
+    public class SelectableTextBlock : TextBlock, IInlineHost
     {
-        public static readonly StyledProperty<bool> IsTextSelectionEnabledProperty =
+        public static readonly DirectProperty<SelectableTextBlock, int> SelectionStartProperty =
-            AvaloniaProperty.Register<RichTextBlock, bool>(nameof(IsTextSelectionEnabled), false);
+            AvaloniaProperty.RegisterDirect<SelectableTextBlock, int>(
-
-        public static readonly DirectProperty<RichTextBlock, int> SelectionStartProperty =
-            AvaloniaProperty.RegisterDirect<RichTextBlock, int>(
                 nameof(SelectionStart),
                 o => o.SelectionStart,
                 (o, v) => o.SelectionStart = v);
 
-        public static readonly DirectProperty<RichTextBlock, int> SelectionEndProperty =
+        public static readonly DirectProperty<SelectableTextBlock, int> SelectionEndProperty =
-            AvaloniaProperty.RegisterDirect<RichTextBlock, int>(
+            AvaloniaProperty.RegisterDirect<SelectableTextBlock, int>(
                 nameof(SelectionEnd),
                 o => o.SelectionEnd,
                 (o, v) => o.SelectionEnd = v);
 
-        public static readonly DirectProperty<RichTextBlock, string> SelectedTextProperty =
+        public static readonly DirectProperty<SelectableTextBlock, string> SelectedTextProperty =
-            AvaloniaProperty.RegisterDirect<RichTextBlock, string>(
+            AvaloniaProperty.RegisterDirect<SelectableTextBlock, string>(
                 nameof(SelectedText),
                 o => o.SelectedText);
 
         public static readonly StyledProperty<IBrush?> SelectionBrushProperty =
-            AvaloniaProperty.Register<RichTextBlock, IBrush?>(nameof(SelectionBrush), Brushes.Blue);
+            AvaloniaProperty.Register<SelectableTextBlock, IBrush?>(nameof(SelectionBrush), Brushes.Blue);
 
-        /// <summary>
-        /// Defines the <see cref="Inlines"/> property.
-        /// </summary>
-        public static readonly StyledProperty<InlineCollection?> InlinesProperty =
-            AvaloniaProperty.Register<RichTextBlock, InlineCollection?>(
-                nameof(Inlines));
 
-        public static readonly DirectProperty<TextBox, bool> CanCopyProperty =
+        public static readonly DirectProperty<SelectableTextBlock, bool> CanCopyProperty =
-            AvaloniaProperty.RegisterDirect<TextBox, bool>(
+            AvaloniaProperty.RegisterDirect<SelectableTextBlock, bool>(
                 nameof(CanCopy),
                 o => o.CanCopy);
 
         public static readonly RoutedEvent<RoutedEventArgs> CopyingToClipboardEvent =
-            RoutedEvent.Register<RichTextBlock, RoutedEventArgs>(
+            RoutedEvent.Register<SelectableTextBlock, RoutedEventArgs>(
                 nameof(CopyingToClipboard), RoutingStrategies.Bubble);
 
         private bool _canCopy;
         private int _selectionStart;
         private int _selectionEnd;
         private int _wordSelectionStart = -1;
-        private IReadOnlyList<TextRun>? _textRuns;
 
-        static RichTextBlock()
+        static SelectableTextBlock()
         {
-            FocusableProperty.OverrideDefaultValue(typeof(RichTextBlock), true);
+            FocusableProperty.OverrideDefaultValue(typeof(SelectableTextBlock), true);
-
+            AffectsRender<SelectableTextBlock>(SelectionStartProperty, SelectionEndProperty, SelectionBrushProperty);
-            AffectsRender<RichTextBlock>(SelectionStartProperty, SelectionEndProperty, SelectionBrushProperty, IsTextSelectionEnabledProperty);
         }
 
-        public RichTextBlock()
+        public event EventHandler<RoutedEventArgs>? CopyingToClipboard
         {
-            Inlines = new InlineCollection
+            add => AddHandler(CopyingToClipboardEvent, value);
-            {
+            remove => RemoveHandler(CopyingToClipboardEvent, value);
-                Parent = this,
-                InlineHost = this
-            };
         }
 
         /// <summary>
@@ -99,6 +84,8 @@ namespace Avalonia.Controls
                 if (SetAndRaise(SelectionStartProperty, ref _selectionStart, value))
                 {
                     RaisePropertyChanged(SelectedTextProperty, "", "");
+
+                    UpdateCommandStates();
                 }
             }
         }
@@ -114,6 +101,8 @@ namespace Avalonia.Controls
                 if (SetAndRaise(SelectionEndProperty, ref _selectionEnd, value))
                 {
                     RaisePropertyChanged(SelectedTextProperty, "", "");
+
+                    UpdateCommandStates();
                 }
             }
         }
@@ -126,25 +115,6 @@ namespace Avalonia.Controls
             get => GetSelection();
         }
 
-        /// <summary>
-        /// Gets or sets a value that indicates whether text selection is enabled, either through user action or calling selection-related API.
-        /// </summary>
-        public bool IsTextSelectionEnabled
-        {
-            get => GetValue(IsTextSelectionEnabledProperty);
-            set => SetValue(IsTextSelectionEnabledProperty, value);
-        }
-
-        /// <summary>
-        /// Gets or sets the inlines.
-        /// </summary>
-        [Content]
-        public InlineCollection? Inlines
-        {
-            get => GetValue(InlinesProperty);
-            set => SetValue(InlinesProperty, value);
-        }
-
         /// <summary>
         /// Property for determining if the Copy command can be executed.
         /// </summary>
@@ -154,20 +124,12 @@ namespace Avalonia.Controls
             private set => SetAndRaise(CanCopyProperty, ref _canCopy, value);
         }
 
-        public event EventHandler<RoutedEventArgs>? CopyingToClipboard
-        {
-            add => AddHandler(CopyingToClipboardEvent, value);
-            remove => RemoveHandler(CopyingToClipboardEvent, value);
-        }
-
-        internal bool HasComplexContent => Inlines != null && Inlines.Count > 0;
-
         /// <summary>
         /// Copies the current selection to the Clipboard.
         /// </summary>
         public async void Copy()
         {
-            if (_canCopy || !IsTextSelectionEnabled)
+            if (!_canCopy)
             {
                 return;
             }
@@ -188,45 +150,13 @@ namespace Avalonia.Controls
                 await ((IClipboard)AvaloniaLocator.Current.GetRequiredService(typeof(IClipboard)))
                     .SetTextAsync(text);
             }
-        }
+        }        
-
-        protected override void RenderTextLayout(DrawingContext context, Point origin)
-        {
-            var selectionStart = SelectionStart;
-            var selectionEnd = SelectionEnd;
-            var selectionBrush = SelectionBrush;
-
-            var selectionEnabled = IsTextSelectionEnabled;
-
-            if (selectionEnabled && selectionStart != selectionEnd && selectionBrush != null)
-            {
-                var start = Math.Min(selectionStart, selectionEnd);
-                var length = Math.Max(selectionStart, selectionEnd) - start;
-
-                var rects = TextLayout.HitTestTextRange(start, length);
-
-                using (context.PushPostTransform(Matrix.CreateTranslation(origin)))
-                {
-                    foreach (var rect in rects)
-                    {
-                        context.FillRectangle(selectionBrush, PixelRect.FromRect(rect, 1).ToRect(1));
-                    }
-                }
-            }
-
-            base.RenderTextLayout(context, origin);
-        }
 
         /// <summary>
         /// Select all text in the TextBox
         /// </summary>
         public void SelectAll()
         {
-            if (!IsTextSelectionEnabled)
-            {
-                return;
-            }
-
             var text = Text;
 
             SelectionStart = 0;
@@ -238,94 +168,52 @@ namespace Avalonia.Controls
         /// </summary>
         public void ClearSelection()
         {
-            if (!IsTextSelectionEnabled)
-            {
-                return;
-            }
-
             SelectionEnd = SelectionStart;
         }
 
-        protected void AddText(string? text)
+        protected override void OnGotFocus(GotFocusEventArgs e)
         {
-            if (string.IsNullOrEmpty(text))
+            base.OnGotFocus(e);
-            {
-                return;
-            }
-
-            if (!HasComplexContent && string.IsNullOrEmpty(_text))
-            {
-                _text = text;
-            }
-            else
-            {
-                if (!string.IsNullOrEmpty(_text))
-                {
-                    Inlines?.Add(_text);
-
-                    _text = null;
-                }
-
-                Inlines?.Add(text);
-            }
-        }
 
-        protected override string? GetText()
+            UpdateCommandStates();
-        {
-            return _text ?? Inlines?.Text;
         }
 
-        protected override void SetText(string? text)
+        protected override void OnLostFocus(RoutedEventArgs e)
         {
-            var oldValue = GetText();
+            base.OnLostFocus(e);
 
-            AddText(text);
+            if ((ContextFlyout == null || !ContextFlyout.IsOpen) &&
+               (ContextMenu == null || !ContextMenu.IsOpen))
+            {
+                ClearSelection();
+            }
 
-            RaisePropertyChanged(TextProperty, oldValue, text);
+            UpdateCommandStates();
         }
 
-        /// <summary>
+        protected override void RenderTextLayout(DrawingContext context, Point origin)
-        /// Creates the <see cref="TextLayout"/> used to render the text.
-        /// </summary>
-        /// <returns>A <see cref="TextLayout"/> object.</returns>
-        protected override TextLayout CreateTextLayout(string? text)
         {
-            var typeface = new Typeface(FontFamily, FontStyle, FontWeight, FontStretch);
+            var selectionStart = SelectionStart;
-            var defaultProperties = new GenericTextRunProperties(
+            var selectionEnd = SelectionEnd;
-                typeface,
+            var selectionBrush = SelectionBrush;
-                FontSize,
-                TextDecorations,
-                Foreground);
-
-            var paragraphProperties = new GenericTextParagraphProperties(FlowDirection, TextAlignment, true, false,
-                defaultProperties, TextWrapping, LineHeight, 0);
-
-            ITextSource textSource;
 
-            if (_textRuns != null)
+            if (selectionStart != selectionEnd && selectionBrush != null)
             {
-                textSource = new InlinesTextSource(_textRuns);
+                var start = Math.Min(selectionStart, selectionEnd);
-            }
+                var length = Math.Max(selectionStart, selectionEnd) - start;
-            else
-            {
-                textSource = new SimpleTextSource((text ?? "").AsMemory(), defaultProperties);
-            }
 
-            return new TextLayout(
+                var rects = TextLayout.HitTestTextRange(start, length);
-                textSource,
-                paragraphProperties,
-                TextTrimming,
-                _constraint.Width,
-                _constraint.Height,
-                maxLines: MaxLines,
-                lineHeight: LineHeight);
-        }
 
-        protected override void OnLostFocus(RoutedEventArgs e)
+                using (context.PushPostTransform(Matrix.CreateTranslation(origin)))
-        {
+                {
-            base.OnLostFocus(e);
+                    foreach (var rect in rects)
+                    {
+                        context.FillRectangle(selectionBrush, PixelRect.FromRect(rect, 1).ToRect(1));
+                    }
+                }
+            }
 
-            ClearSelection();
+            base.RenderTextLayout(context, origin);
         }
 
         protected override void OnKeyDown(KeyEventArgs e)
@@ -352,11 +240,6 @@ namespace Avalonia.Controls
         {
             base.OnPointerPressed(e);
 
-            if (!IsTextSelectionEnabled)
-            {
-                return;
-            }
-
             var text = Text;
             var clickInfo = e.GetCurrentPoint(this);
 
@@ -435,11 +318,6 @@ namespace Avalonia.Controls
         {
             base.OnPointerMoved(e);
 
-            if (!IsTextSelectionEnabled)
-            {
-                return;
-            }
-
             // selection should not change during pointer move if the user right clicks
             if (e.Pointer.Captured == this && e.GetCurrentPoint(this).Properties.IsLeftButtonPressed)
             {
@@ -486,11 +364,6 @@ namespace Avalonia.Controls
         {
             base.OnPointerReleased(e);
 
-            if (!IsTextSelectionEnabled)
-            {
-                return;
-            }
-
             if (e.Pointer.Captured != this)
             {
                 return;
@@ -521,100 +394,15 @@ namespace Avalonia.Controls
             e.Pointer.Capture(null);
         }
 
-        protected override void OnPropertyChanged(AvaloniaPropertyChangedEventArgs change)
+        private void UpdateCommandStates()
-        {
-            base.OnPropertyChanged(change);
-
-            switch (change.Property.Name)
-            {
-                case nameof(Inlines):
-                    {
-                        OnInlinesChanged(change.OldValue as InlineCollection, change.NewValue as InlineCollection);
-                        InvalidateTextLayout();
-                        break;
-                    }
-            }
-        }
-
-        protected override Size MeasureOverride(Size availableSize)
         {
-            if(_textRuns != null)
+            var text = GetSelection();
-            {
-                LogicalChildren.Clear();
-
-                VisualChildren.Clear();
-
-                _textRuns = null;
-            }
-
-            if (Inlines != null && Inlines.Count > 0)
-            {
-                var inlines = Inlines;
-
-                var textRuns = new List<TextRun>();
-
-                foreach (var inline in inlines)
-                {
-                    inline.BuildTextRun(textRuns);
-                }
-
-                foreach (var textRun in textRuns)
-                {
-                    if (textRun is EmbeddedControlRun controlRun &&
-                        controlRun.Control is Control control)
-                    {
-                        LogicalChildren.Add(control);
-
-                        VisualChildren.Add(control);
-
-                        control.Measure(Size.Infinity);
-                    }
-                }
-
-                _textRuns = textRuns;
-            }
-
-            return base.MeasureOverride(availableSize);
-        }
-
-        protected override Size ArrangeOverride(Size finalSize)
-        {
-            if (HasComplexContent)
-            {
-                var currentY = 0.0;
-
-                foreach (var textLine in TextLayout.TextLines)
-                {
-                    var currentX = textLine.Start;
-
-                    foreach (var run in textLine.TextRuns)
-                    {
-                        if (run is DrawableTextRun drawable)
-                        {
-                            if (drawable is EmbeddedControlRun controlRun
-                                && controlRun.Control is Control control)
-                            {
-                                control.Arrange(new Rect(new Point(currentX, currentY), control.DesiredSize));
-                            }
-
-                            currentX += drawable.Size.Width;
-                        }
-                    }
 
-                    currentY += textLine.Height;
+            CanCopy = !string.IsNullOrEmpty(text);
-                }
-            }
-           
-            return base.ArrangeOverride(finalSize);
         }
 
         private string GetSelection()
         {
-            if (!IsTextSelectionEnabled)
-            {
-                return "";
-            }
-
             var text = GetText();
 
             if (string.IsNullOrEmpty(text))
@@ -638,59 +426,5 @@ namespace Avalonia.Controls
 
             return selectedText;
         }
-
-        private void OnInlinesChanged(InlineCollection? oldValue, InlineCollection? newValue)
-        {
-            if (oldValue is not null)
-            {
-                oldValue.Parent = null;
-                oldValue.InlineHost = null;
-                oldValue.Invalidated -= (s, e) => InvalidateTextLayout();
-            }
-
-            if (newValue is not null)
-            {
-                newValue.Parent = this;
-                newValue.InlineHost = this;
-                newValue.Invalidated += (s, e) => InvalidateTextLayout();
-            }
-        }
-
-        void IInlineHost.Invalidate()
-        {
-            InvalidateTextLayout();
-        }
-
-        private readonly struct InlinesTextSource : ITextSource
-        {
-            private readonly IReadOnlyList<TextRun> _textRuns;
-
-            public InlinesTextSource(IReadOnlyList<TextRun> textRuns)
-            {
-                _textRuns = textRuns;
-            }
-
-            public TextRun? GetTextRun(int textSourceIndex)
-            {
-                var currentPosition = 0;
-
-                foreach (var textRun in _textRuns)
-                {
-                    if (textRun.TextSourceLength == 0)
-                    {
-                        continue;
-                    }
-
-                    if (currentPosition >= textSourceIndex)
-                    {
-                        return textRun;
-                    }
-
-                    currentPosition += textRun.TextSourceLength;
-                }
-
-                return null;
-            }
-        }
     }
 }

src/Avalonia.Controls/TextBlock.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 using Avalonia.Automation.Peers;
 using Avalonia.Controls.Documents;
 using Avalonia.Layout;
@@ -12,7 +13,7 @@ namespace Avalonia.Controls
     /// <summary>
     /// A control that displays a block of text.
     /// </summary>
-    public class TextBlock : Control, IAddChild<string>
+    public class TextBlock : Control, IInlineHost
     {
         /// <summary>
         /// Defines the <see cref="Background"/> property.
@@ -96,15 +97,15 @@ namespace Avalonia.Controls
         public static readonly DirectProperty<TextBlock, string?> TextProperty =
             AvaloniaProperty.RegisterDirect<TextBlock, string?>(
                 nameof(Text),
-                o => o.Text,
+                o => o.GetText(),
-                (o, v) => o.Text = v);
+                (o, v) => o.SetText(v));
 
         /// <summary>
         /// Defines the <see cref="TextAlignment"/> property.
         /// </summary>
         public static readonly AttachedProperty<TextAlignment> TextAlignmentProperty =
             AvaloniaProperty.RegisterAttached<TextBlock, Control, TextAlignment>(
-                nameof(TextAlignment), 
+                nameof(TextAlignment),
                 defaultValue: TextAlignment.Start,
                 inherits: true);
 
@@ -112,14 +113,14 @@ namespace Avalonia.Controls
         /// Defines the <see cref="TextWrapping"/> property.
         /// </summary>
         public static readonly AttachedProperty<TextWrapping> TextWrappingProperty =
-            AvaloniaProperty.RegisterAttached<TextBlock, Control, TextWrapping>(nameof(TextWrapping), 
+            AvaloniaProperty.RegisterAttached<TextBlock, Control, TextWrapping>(nameof(TextWrapping),
                 inherits: true);
 
         /// <summary>
         /// Defines the <see cref="TextTrimming"/> property.
         /// </summary>
         public static readonly AttachedProperty<TextTrimming> TextTrimmingProperty =
-            AvaloniaProperty.RegisterAttached<TextBlock, Control, TextTrimming>(nameof(TextTrimming), 
+            AvaloniaProperty.RegisterAttached<TextBlock, Control, TextTrimming>(nameof(TextTrimming),
                 defaultValue: TextTrimming.None,
                 inherits: true);
 
@@ -129,9 +130,17 @@ namespace Avalonia.Controls
         public static readonly StyledProperty<TextDecorationCollection?> TextDecorationsProperty =
             AvaloniaProperty.Register<TextBlock, TextDecorationCollection?>(nameof(TextDecorations));
 
+        /// <summary>
+        /// Defines the <see cref="Inlines"/> property.
+        /// </summary>
+        public static readonly StyledProperty<InlineCollection?> InlinesProperty =
+            AvaloniaProperty.Register<TextBlock, InlineCollection?>(
+                nameof(Inlines));
+
         internal string? _text;
         protected TextLayout? _textLayout;
         protected Size _constraint;
+        private IReadOnlyList<TextRun>? _textRuns;
 
         /// <summary>
         /// Initializes static members of the <see cref="TextBlock"/> class.
@@ -139,10 +148,19 @@ namespace Avalonia.Controls
         static TextBlock()
         {
             ClipToBoundsProperty.OverrideDefaultValue<TextBlock>(true);
-            
+
             AffectsRender<TextBlock>(BackgroundProperty, ForegroundProperty);
         }
 
+        public TextBlock()
+        {
+            Inlines = new InlineCollection
+            {
+                LogicalChildren = LogicalChildren,
+                InlineHost = this
+            };
+        }
+
         /// <summary>
         /// Gets the <see cref="TextLayout"/> used to render the text.
         /// </summary>
@@ -288,9 +306,21 @@ namespace Avalonia.Controls
             get => GetValue(TextDecorationsProperty);
             set => SetValue(TextDecorationsProperty, value);
         }
-        
+
+        /// <summary>
+        /// Gets or sets the inlines.
+        /// </summary>
+        [Content]
+        public InlineCollection? Inlines
+        {
+            get => GetValue(InlinesProperty);
+            set => SetValue(InlinesProperty, value);
+        }
+
         protected override bool BypassFlowDirectionPolicies => true;
 
+        internal bool HasComplexContent => Inlines != null && Inlines.Count > 0;
+
         /// <summary>
         /// The BaselineOffset property provides an adjustment to baseline offset
         /// </summary>
@@ -513,19 +543,30 @@ namespace Avalonia.Controls
             TextLayout.Draw(context, origin);
         }
 
-        void IAddChild<string>.AddChild(string text)
-        {
-            _text = text;
-        }
-
         protected virtual string? GetText()
         {
-            return _text;
+            return _text ?? Inlines?.Text;
         }
 
         protected virtual void SetText(string? text)
         {
-            SetAndRaise(TextProperty, ref _text, text);
+            if (Inlines != null && Inlines.Count > 0)
+            {
+                var oldValue = Inlines.Text;
+
+                if (!string.IsNullOrEmpty(text))
+                {
+                    Inlines.Add(text);
+                }
+
+                text = Inlines.Text;
+
+                RaisePropertyChanged(TextProperty, oldValue, text);
+            }
+            else
+            {
+                SetAndRaise(TextProperty, ref _text, text);
+            }
         }
 
         /// <summary>
@@ -534,8 +575,10 @@ namespace Avalonia.Controls
         /// <returns>A <see cref="TextLayout"/> object.</returns>
         protected virtual TextLayout CreateTextLayout(string? text)
         {
+            var typeface = new Typeface(FontFamily, FontStyle, FontWeight, FontStretch);
+
             var defaultProperties = new GenericTextRunProperties(
-                new Typeface(FontFamily, FontStyle, FontWeight, FontStretch),
+                typeface,
                 FontSize,
                 TextDecorations,
                 Foreground);
@@ -543,8 +586,19 @@ namespace Avalonia.Controls
             var paragraphProperties = new GenericTextParagraphProperties(FlowDirection, TextAlignment, true, false,
                 defaultProperties, TextWrapping, LineHeight, 0);
 
+            ITextSource textSource;
+
+            if (_textRuns != null)
+            {
+                textSource = new InlinesTextSource(_textRuns);
+            }
+            else
+            {
+                textSource = new SimpleTextSource((text ?? "").AsMemory(), defaultProperties);
+            }
+
             return new TextLayout(
-                new SimpleTextSource((text ?? "").AsMemory(), defaultProperties),
+                textSource,
                 paragraphProperties,
                 TextTrimming,
                 _constraint.Width,
@@ -560,6 +614,8 @@ namespace Avalonia.Controls
         {
             _textLayout = null;
 
+            InvalidateVisual();
+
             InvalidateMeasure();
         }
 
@@ -573,7 +629,46 @@ namespace Avalonia.Controls
 
             _textLayout = null;
 
-            InvalidateArrange();
+            var inlines = Inlines;
+
+            if (HasComplexContent)
+            {
+                if (_textRuns != null)
+                {
+                    foreach (var textRun in _textRuns)
+                    {
+                        if (textRun is EmbeddedControlRun controlRun &&
+                            controlRun.Control is Control control)
+                        {
+                            VisualChildren.Remove(control);
+
+                            LogicalChildren.Remove(control);
+                        }
+                    }
+                }
+
+                var textRuns = new List<TextRun>();
+
+                foreach (var inline in inlines!)
+                {
+                    inline.BuildTextRun(textRuns);
+                }
+
+                foreach (var textRun in textRuns)
+                {
+                    if (textRun is EmbeddedControlRun controlRun &&
+                        controlRun.Control is Control control)
+                    {
+                        VisualChildren.Add(control);
+
+                        LogicalChildren.Add(control);
+
+                        control.Measure(Size.Infinity);
+                    }
+                }
+
+                _textRuns = textRuns;
+            }
 
             var measuredSize = TextLayout.Bounds.Size.Inflate(padding);
 
@@ -584,16 +679,11 @@ namespace Avalonia.Controls
         {
             var textWidth = Math.Ceiling(TextLayout.Bounds.Width);
 
-            if(finalSize.Width < textWidth)
+            if (finalSize.Width < textWidth)
             {
                 finalSize = finalSize.WithWidth(textWidth);
             }
 
-            if (MathUtilities.AreClose(_constraint.Width, finalSize.Width))
-            {
-                return finalSize;
-            }
-
             var scale = LayoutHelper.GetLayoutScale(this);
 
             var padding = LayoutHelper.RoundLayoutThickness(Padding, scale, scale);
@@ -602,6 +692,32 @@ namespace Avalonia.Controls
 
             _textLayout = null;
 
+            if (HasComplexContent)
+            {
+                var currentY = padding.Top;
+
+                foreach (var textLine in TextLayout.TextLines)
+                {
+                    var currentX = padding.Left + textLine.Start;
+
+                    foreach (var run in textLine.TextRuns)
+                    {
+                        if (run is DrawableTextRun drawable)
+                        {
+                            if (drawable is EmbeddedControlRun controlRun
+                                && controlRun.Control is Control control)
+                            {
+                                control.Arrange(new Rect(new Point(currentX, currentY), control.DesiredSize));
+                            }
+
+                            currentX += drawable.Size.Width;
+                        }
+                    }
+
+                    currentY += textLine.Height;
+                }
+            }
+
             return finalSize;
         }
 
@@ -610,42 +726,70 @@ namespace Avalonia.Controls
             return new TextBlockAutomationPeer(this);
         }
 
-        private static bool IsValidMaxLines(int maxLines) => maxLines >= 0;
-
-        private static bool IsValidLineHeight(double lineHeight) => double.IsNaN(lineHeight) || lineHeight > 0;
-
         protected override void OnPropertyChanged(AvaloniaPropertyChangedEventArgs change)
         {
             base.OnPropertyChanged(change);
 
             switch (change.Property.Name)
             {
-                case nameof (FontSize):
+                case nameof(FontSize):
-                case nameof (FontWeight):
+                case nameof(FontWeight):
-                case nameof (FontStyle):
+                case nameof(FontStyle):
-                case nameof (FontFamily):
+                case nameof(FontFamily):
-                case nameof (FontStretch):
+                case nameof(FontStretch):
+
+                case nameof(TextWrapping):
+                case nameof(TextTrimming):
+                case nameof(TextAlignment):
+
+                case nameof(FlowDirection):
+
+                case nameof(Padding):
+                case nameof(LineHeight):
+                case nameof(MaxLines):
+
+                case nameof(Text):
+                case nameof(TextDecorations):
+                case nameof(Foreground):
+                    {
+                        InvalidateTextLayout();
+                        break;
+                    }
+                case nameof(Inlines):
+                    {
+                        OnInlinesChanged(change.OldValue as InlineCollection, change.NewValue as InlineCollection);
+                        InvalidateTextLayout();
+                        break;
+                    }
+            }
+        }
 
-                case nameof (TextWrapping):
+        private static bool IsValidMaxLines(int maxLines) => maxLines >= 0;
-                case nameof (TextTrimming):
-                case nameof (TextAlignment):
 
-                case nameof (FlowDirection):
+        private static bool IsValidLineHeight(double lineHeight) => double.IsNaN(lineHeight) || lineHeight > 0;
 
-                case nameof (Padding):
+        private void OnInlinesChanged(InlineCollection? oldValue, InlineCollection? newValue)
-                case nameof (LineHeight):
+        {
-                case nameof (MaxLines):
+            if (oldValue is not null)
+            {
+                oldValue.LogicalChildren = null;
+                oldValue.InlineHost = null;
+                oldValue.Invalidated -= (s, e) => InvalidateTextLayout();
+            }
 
-                case nameof (Text):
+            if (newValue is not null)
-                case nameof (TextDecorations):
+            {
-                case nameof (Foreground):
+                newValue.LogicalChildren = LogicalChildren;
-                {
+                newValue.InlineHost = this;
-                    InvalidateTextLayout();
+                newValue.Invalidated += (s, e) => InvalidateTextLayout();
-                    break;
-                }
             }
         }
 
+        void IInlineHost.Invalidate()
+        {
+            InvalidateTextLayout();
+        }
+
         protected readonly struct SimpleTextSource : ITextSource
         {
             private readonly ReadOnlySlice<char> _text;
@@ -674,5 +818,46 @@ namespace Avalonia.Controls
                 return new TextCharacters(runText, _defaultProperties);
             }
         }
+
+        private readonly struct InlinesTextSource : ITextSource
+        {
+            private readonly IReadOnlyList<TextRun> _textRuns;
+
+            public InlinesTextSource(IReadOnlyList<TextRun> textRuns)
+            {
+                _textRuns = textRuns;
+            }
+
+            public IReadOnlyList<TextRun> TextRuns => _textRuns;
+
+            public TextRun? GetTextRun(int textSourceIndex)
+            {
+                var currentPosition = 0;
+
+                foreach (var textRun in _textRuns)
+                {
+                    if (textRun.TextSourceLength == 0)
+                    {
+                        continue;
+                    }
+
+                    if (textSourceIndex >= currentPosition + textRun.TextSourceLength)
+                    {
+                        currentPosition += textRun.TextSourceLength;
+
+                        continue;
+                    }
+
+                    if (textRun is TextCharacters)
+                    {
+                        return new TextCharacters(textRun.Text.Skip(Math.Max(0, textSourceIndex - currentPosition)), textRun.Properties!);
+                    }
+
+                    return textRun;
+                }
+
+                return null;
+            }
+        }
     }
 }

src/Avalonia.Themes.Fluent/Controls/FluentControls.xaml

@@ -68,7 +68,7 @@
                 <ResourceInclude Source="avares://Avalonia.Themes.Fluent/Controls/Slider.xaml" />
                 <!--  ManagedFileChooser comes last because it uses (and overrides) styles for a multitude of other controls...the dialogs were originally UserControls, after all  -->
                 <ResourceInclude Source="avares://Avalonia.Themes.Fluent/Controls/ManagedFileChooser.xaml" />
-                <ResourceInclude Source="avares://Avalonia.Themes.Fluent/Controls/RichTextBlock.xaml"/>
+                <ResourceInclude Source="avares://Avalonia.Themes.Fluent/Controls/SelectableTextBlock.xaml"/>
             </ResourceDictionary.MergedDictionaries>
         </ResourceDictionary>
     </Styles.Resources>

src/Avalonia.Themes.Fluent/Controls/RichTextBlock.xaml

@@ -1,14 +0,0 @@
-<ResourceDictionary xmlns="https://github.com/avaloniaui"
-        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
-    <Design.PreviewWith>
-        <RichTextBlock IsTextSelectionEnabled="True" Text="Preview"/>
-    </Design.PreviewWith>
-
-  <ControlTheme x:Key="{x:Type RichTextBlock}" TargetType="RichTextBlock">
-    <Style Selector="^[IsTextSelectionEnabled=True]">
-      <Setter Property="Cursor" Value="IBeam" />
-    </Style>
-  </ControlTheme>
-
-
-</ResourceDictionary>

src/Avalonia.Themes.Fluent/Controls/SelectableTextBlock.xaml

@@ -0,0 +1,18 @@
+<ResourceDictionary xmlns="https://github.com/avaloniaui"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+  <Design.PreviewWith>
+    <SelectableTextBlock Text="Preview" />
+  </Design.PreviewWith>
+
+  <MenuFlyout x:Key="SelectableTextBlockContextFlyout" Placement="Bottom">
+    <MenuItem x:Name="SelectableTextBlockContextFlyoutCopyItem" Header="Copy" Command="{Binding $parent[SelectableTextBlock].Copy}"
+              IsEnabled="{Binding $parent[SelectableTextBlock].CanCopy}" InputGesture="{x:Static TextBox.CopyGesture}" />
+  </MenuFlyout>
+
+  <ControlTheme x:Key="{x:Type SelectableTextBlock}" TargetType="SelectableTextBlock">
+    <Style Selector="^[IsEnabled=True]">
+      <Setter Property="Cursor" Value="IBeam" />
+      <Setter Property="ContextFlyout" Value="{StaticResource SelectableTextBlockContextFlyout}" />
+    </Style>
+  </ControlTheme>
+</ResourceDictionary>

src/Avalonia.Themes.Simple/Controls/RichTextBlock.xaml

@@ -1,14 +0,0 @@
-<ResourceDictionary xmlns="https://github.com/avaloniaui"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
-  <Design.PreviewWith>
-    <RichTextBlock IsTextSelectionEnabled="True"
-                   Text="Preview" />
-  </Design.PreviewWith>
-
-  <ControlTheme x:Key="{x:Type RichTextBlock}"
-                TargetType="RichTextBlock">
-    <Style Selector="^[IsTextSelectionEnabled=True]">
-      <Setter Property="Cursor" Value="IBeam" />
-    </Style>
-  </ControlTheme>
-</ResourceDictionary>

src/Avalonia.Themes.Simple/Controls/SelectableTextBlock.xaml

@@ -0,0 +1,18 @@
+<ResourceDictionary xmlns="https://github.com/avaloniaui"
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+  <Design.PreviewWith>
+    <SelectableTextBlock Text="Preview" />
+  </Design.PreviewWith>
+
+  <MenuFlyout x:Key="SelectableTextBlockContextFlyout" Placement="Bottom">
+    <MenuItem x:Name="SelectableTextBlockContextFlyoutCopyItem" Header="Copy" Command="{Binding $parent[SelectableTextBlock].Copy}"
+              IsEnabled="{Binding $parent[SelectableTextBlock].CanCopy}" InputGesture="{x:Static TextBox.CopyGesture}" />
+  </MenuFlyout>
+
+  <ControlTheme x:Key="{x:Type SelectableTextBlock}" TargetType="SelectableTextBlock">
+    <Style Selector="^[IsEnabled=True]">
+      <Setter Property="Cursor" Value="IBeam" />
+      <Setter Property="ContextFlyout" Value="{StaticResource SelectableTextBlockContextFlyout}" />
+    </Style>
+  </ControlTheme>
+</ResourceDictionary>

src/Avalonia.Themes.Simple/Controls/SimpleControls.xaml

@@ -64,7 +64,7 @@
         <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/SplitView.xaml" />
         <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/ManagedFileChooser.xaml" />
         <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/SplitButton.xaml" />
-        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/RichTextBlock.xaml" />
+        <ResourceInclude Source="avares://Avalonia.Themes.Simple/Controls/SelectableTextBlock.xaml" />
       </ResourceDictionary.MergedDictionaries>
     </ResourceDictionary>
   </Styles.Resources>

src/Skia/Avalonia.Skia/TextShaperImpl.cs

@@ -64,7 +64,7 @@ namespace Avalonia.Skia
 
                     var glyphOffset = GetGlyphOffset(glyphPositions, i, textScale);
 
-                    if(glyphIndex == 0 && text.Buffer.Span[glyphCluster] == '\t')
+                    if(text.Buffer.Span[glyphCluster] == '\t')
                     {
                         glyphIndex = typeface.GetGlyph(' ');
 

src/Windows/Avalonia.Direct2D1/Media/TextShaperImpl.cs

@@ -64,7 +64,7 @@ namespace Avalonia.Direct2D1.Media
 
                     var glyphOffset = GetGlyphOffset(glyphPositions, i, textScale);
 
-                    if (glyphIndex == 0 && text.Buffer.Span[glyphCluster] == '\t')
+                    if (text.Buffer.Span[glyphCluster] == '\t')
                     {
                         glyphIndex = typeface.GetGlyph(' ');
 

tests/Avalonia.Controls.UnitTests/RichTextBlockTests.cs

@@ -1,132 +0,0 @@
-using Avalonia.Controls.Documents;
-using Avalonia.Controls.Presenters;
-using Avalonia.Controls.Templates;
-using Avalonia.Media;
-using Avalonia.UnitTests;
-using Xunit;
-
-namespace Avalonia.Controls.UnitTests
-{
-    public class RichTextBlockTests
-    {
-        [Fact]
-        public void Changing_InlinesCollection_Should_Invalidate_Measure()
-        {
-            using (UnitTestApplication.Start(TestServices.MockPlatformRenderInterface))
-            {
-                var target = new RichTextBlock();
-
-                target.Measure(Size.Infinity);
-
-                Assert.True(target.IsMeasureValid);
-
-                target.Inlines.Add(new Run("Hello"));
-
-                Assert.False(target.IsMeasureValid);
-
-                target.Measure(Size.Infinity);
-
-                Assert.True(target.IsMeasureValid);
-            }
-        }
-
-        [Fact]
-        public void Changing_Inlines_Properties_Should_Invalidate_Measure()
-        {
-            using (UnitTestApplication.Start(TestServices.MockPlatformRenderInterface))
-            {
-                var target = new RichTextBlock();
-
-                var inline = new Run("Hello");
-
-                target.Inlines.Add(inline);
-
-                target.Measure(Size.Infinity);
-
-                Assert.True(target.IsMeasureValid);
-
-                inline.Foreground = Brushes.Green;
-
-                Assert.False(target.IsMeasureValid);
-            }
-        }
-
-        [Fact]
-        public void Changing_Inlines_Should_Invalidate_Measure()
-        {
-            using (UnitTestApplication.Start(TestServices.MockPlatformRenderInterface))
-            {
-                var target = new RichTextBlock();
-
-                var inlines = new InlineCollection { new Run("Hello") };
-
-                target.Measure(Size.Infinity);
-
-                Assert.True(target.IsMeasureValid);
-
-                target.Inlines = inlines;
-
-                Assert.False(target.IsMeasureValid);
-            }
-        }
-
-        [Fact]
-        public void Changing_Inlines_Should_Reset_Inlines_Parent()
-        {
-            using (UnitTestApplication.Start(TestServices.MockPlatformRenderInterface))
-            {
-                var target = new RichTextBlock();
-
-                var run = new Run("Hello");
-
-                target.Inlines.Add(run);
-
-                target.Measure(Size.Infinity);
-
-                Assert.True(target.IsMeasureValid);
-
-                target.Inlines = null;
-
-                Assert.Null(run.Parent);
-
-                target.Inlines = new InlineCollection { run };
-
-                Assert.Equal(target, run.Parent);
-            }
-        }
-
-        [Fact]
-        public void InlineUIContainer_Child_Schould_Be_Arranged()
-        {
-            using (UnitTestApplication.Start(TestServices.StyledWindow))
-            {
-                var target = new RichTextBlock();
-
-                var button = new Button { Content = "12345678" };
-
-                button.Template = new FuncControlTemplate<Button>((parent, scope) =>           
-                        new TextBlock
-                        {
-                            Name = "PART_ContentPresenter",
-                            [!TextBlock.TextProperty] = parent[!ContentControl.ContentProperty],
-                        }.RegisterInNameScope(scope)                                       
-                );
-
-                target.Inlines!.Add("123456");
-                target.Inlines.Add(new InlineUIContainer(button));
-                target.Inlines.Add("123456");
-
-                target.Measure(Size.Infinity);
-
-                Assert.True(button.IsMeasureValid);
-                Assert.Equal(80, button.DesiredSize.Width);
-
-                target.Arrange(new Rect(new Size(200, 50)));
-
-                Assert.True(button.IsArrangeValid);
-
-                Assert.Equal(60, button.Bounds.Left);
-            }
-        }
-    }
-}

tests/Avalonia.Controls.UnitTests/TextBlockTests.cs

@@ -1,5 +1,6 @@
 using System;
 using Avalonia.Controls.Documents;
+using Avalonia.Controls.Templates;
 using Avalonia.Data;
 using Avalonia.Media;
 using Avalonia.Rendering;
@@ -60,5 +61,125 @@ namespace Avalonia.Controls.UnitTests
 
             renderer.Verify(x => x.AddDirty(target), Times.Once);
         }
+
+        [Fact]
+        public void Changing_InlinesCollection_Should_Invalidate_Measure()
+        {
+            using (UnitTestApplication.Start(TestServices.MockPlatformRenderInterface))
+            {
+                var target = new TextBlock();
+
+                target.Measure(Size.Infinity);
+
+                Assert.True(target.IsMeasureValid);
+
+                target.Inlines.Add(new Run("Hello"));
+
+                Assert.False(target.IsMeasureValid);
+
+                target.Measure(Size.Infinity);
+
+                Assert.True(target.IsMeasureValid);
+            }
+        }
+
+        [Fact]
+        public void Changing_Inlines_Properties_Should_Invalidate_Measure()
+        {
+            using (UnitTestApplication.Start(TestServices.MockPlatformRenderInterface))
+            {
+                var target = new TextBlock();
+
+                var inline = new Run("Hello");
+
+                target.Inlines.Add(inline);
+
+                target.Measure(Size.Infinity);
+
+                Assert.True(target.IsMeasureValid);
+
+                inline.Foreground = Brushes.Green;
+
+                Assert.False(target.IsMeasureValid);
+            }
+        }
+
+        [Fact]
+        public void Changing_Inlines_Should_Invalidate_Measure()
+        {
+            using (UnitTestApplication.Start(TestServices.MockPlatformRenderInterface))
+            {
+                var target = new TextBlock();
+
+                var inlines = new InlineCollection { new Run("Hello") };
+
+                target.Measure(Size.Infinity);
+
+                Assert.True(target.IsMeasureValid);
+
+                target.Inlines = inlines;
+
+                Assert.False(target.IsMeasureValid);
+            }
+        }
+
+        [Fact]
+        public void Changing_Inlines_Should_Reset_Inlines_Parent()
+        {
+            using (UnitTestApplication.Start(TestServices.MockPlatformRenderInterface))
+            {
+                var target = new TextBlock();
+
+                var run = new Run("Hello");
+
+                target.Inlines.Add(run);
+
+                target.Measure(Size.Infinity);
+
+                Assert.True(target.IsMeasureValid);
+
+                target.Inlines = null;
+
+                Assert.Null(run.Parent);
+
+                target.Inlines = new InlineCollection { run };
+
+                Assert.Equal(target, run.Parent);
+            }
+        }
+
+        [Fact]
+        public void InlineUIContainer_Child_Schould_Be_Arranged()
+        {
+            using (UnitTestApplication.Start(TestServices.StyledWindow))
+            {
+                var target = new TextBlock();
+
+                var button = new Button { Content = "12345678" };
+
+                button.Template = new FuncControlTemplate<Button>((parent, scope) =>
+                        new TextBlock
+                        {
+                            Name = "PART_ContentPresenter",
+                            [!TextBlock.TextProperty] = parent[!ContentControl.ContentProperty],
+                        }.RegisterInNameScope(scope)
+                );
+
+                target.Inlines!.Add("123456");
+                target.Inlines.Add(new InlineUIContainer(button));
+                target.Inlines.Add("123456");
+
+                target.Measure(Size.Infinity);
+
+                Assert.True(button.IsMeasureValid);
+                Assert.Equal(80, button.DesiredSize.Width);
+
+                target.Arrange(new Rect(new Size(200, 50)));
+
+                Assert.True(button.IsArrangeValid);
+
+                Assert.Equal(60, button.Bounds.Left);
+            }
+        }
     }
 }