More refactoring of FormattedText.

Perspex.Controls/TextBlock.cs

@@ -7,12 +7,17 @@
 namespace Perspex.Controls
 {
     using System;
+    using System.Reactive;
+    using System.Reactive.Linq;
     using Perspex.Media;
     using Perspex.Platform;
     using Splat;
 
     public class TextBlock : Control
     {
+        public static readonly PerspexProperty<string> FontFamilyProperty =
+            PerspexProperty.Register<Control, string>("FontFamily", "Segoe UI", inherits: true);
+
         public static readonly PerspexProperty<double> FontSizeProperty =
             PerspexProperty.Register<Control, double>(
                 "FontSize",
@@ -25,27 +30,24 @@ namespace Perspex.Controls
         public static readonly PerspexProperty<string> TextProperty =
             PerspexProperty.Register<TextBlock, string>("Text");
 
-        private FormattedText formattedText = new FormattedText();
+        private FormattedText formattedText;
 
         public TextBlock()
         {
-            this.GetObservable(TextProperty).Subscribe(x =>
+            Observable.Merge(
-            {
+                this.GetObservable(TextProperty).Select(_ => Unit.Default),
-                this.formattedText.Text = x;
+                this.GetObservable(FontSizeProperty).Select(_ => Unit.Default),
-                this.InvalidateMeasure();
+                this.GetObservable(FontStyleProperty).Select(_ => Unit.Default))
-            });
+                .Subscribe(_ =>
-
+                {
-            this.GetObservable(FontSizeProperty).Subscribe(x =>
+                    if (this.formattedText != null)
-            {
+                    {
-                this.formattedText.FontSize = x;
+                        this.formattedText.Dispose();
-                this.InvalidateMeasure();
+                        this.formattedText = null;
-            });
+                    }
-
+
-            this.GetObservable(FontStyleProperty).Subscribe(x =>
+                    this.InvalidateMeasure();
-            {
+                });
-                this.formattedText.FontStyle = x;
-                this.InvalidateMeasure();
-            });
         }
 
         public string Text
@@ -54,6 +56,12 @@ namespace Perspex.Controls
             set { this.SetValue(TextProperty, value); }
         }
 
+        public string FontFamily
+        {
+            get { return this.GetValue(FontFamilyProperty); }
+            set { this.SetValue(FontFamilyProperty, value); }
+        }
+
         public double FontSize
         {
             get { return this.GetValue(FontSizeProperty); }
@@ -66,6 +74,24 @@ namespace Perspex.Controls
             set { this.SetValue(FontStyleProperty, value); }
         }
 
+        protected FormattedText FormattedText
+        {
+            get
+            {
+                if (this.formattedText == null)
+                {
+                    this.formattedText = new FormattedText(
+                        this.Text, 
+                        this.FontFamily, 
+                        this.FontSize, 
+                        this.FontStyle);
+                }
+
+                return this.formattedText;
+            }
+        }
+
+
         public override void Render(IDrawingContext context)
         {
             Brush background = this.Background;
@@ -75,18 +101,15 @@ namespace Perspex.Controls
                 context.FillRectange(background, new Rect(this.ActualSize));
             }
 
-            context.DrawText(
+            context.DrawText(this.Foreground,  new Point(), this.FormattedText);
-                this.Foreground, 
-                new Rect(this.ActualSize), 
-                this.formattedText);
         }
 
         protected override Size MeasureOverride(Size availableSize)
         {
             if (!string.IsNullOrEmpty(this.Text))
             {
-                this.formattedText.Constraint = availableSize;
+                this.FormattedText.Constraint = availableSize;
-                return this.formattedText.Measure();
+                return this.FormattedText.Measure();
             }
 
             return new Size();

Perspex.Controls/TextBox.cs

@@ -10,9 +10,7 @@ namespace Perspex.Controls
     using System.Linq;
     using Perspex.Controls.Primitives;
     using Perspex.Input;
-    using Perspex.Platform;
     using Perspex.Styling;
-    using Splat;
 
     public class TextBox : TemplatedControl
     {
@@ -160,8 +158,7 @@ namespace Perspex.Controls
         private void OnPointerPressed(object sender, PointerEventArgs e)
         {
             var point = e.GetPosition(this.textBoxView);
-            var hit = this.textBoxView.FormattedText.HitTestPoint(point);
+            this.CaretIndex = this.textBoxView.GetCaretIndex(point);
-            this.CaretIndex = hit.TextPosition + (hit.IsTrailing ? 1 : 0);
         }
     }
 }

Perspex.Controls/TextBoxView.cs

@@ -8,55 +8,29 @@ namespace Perspex.Controls
 {
     using System;
     using Perspex.Media;
-    using Perspex.Platform;
     using Perspex.Threading;
-    using Splat;
 
-    internal class TextBoxView : Control
+    internal class TextBoxView : TextBlock
     {
         private TextBox parent;
 
-        private FormattedText formattedText;
-
         private DispatcherTimer caretTimer;
 
         private bool caretBlink;
 
         public TextBoxView(TextBox parent)
         {
-            this.FormattedText = new FormattedText();
-
-            // TODO: Implement TextBlock.FontFamilyName.
-            this.FormattedText.FontFamilyName = "Segoe UI";
-
-            parent.GetObservable(TextBox.TextProperty).Subscribe(x =>
-            {
-                this.FormattedText.Text = x;
-                this.InvalidateMeasure();
-            });
-
-            this.GetObservable(TextBlock.FontSizeProperty).Subscribe(x =>
-            {
-                this.FormattedText.FontSize = x;
-                this.InvalidateMeasure();
-            });
-
-            this.GetObservable(TextBlock.FontStyleProperty).Subscribe(x =>
-            {
-                this.FormattedText.FontStyle = x;
-                this.InvalidateMeasure();
-            });
-
             this.caretTimer = new DispatcherTimer();
             this.caretTimer.Interval = TimeSpan.FromMilliseconds(500);
             this.caretTimer.Tick += this.CaretTimerTick;
             this.parent = parent;
+            this[!TextProperty] = parent[!TextProperty];
         }
 
-        public FormattedText FormattedText
+        public int GetCaretIndex(Point point)
         {
-            get;
+            var hit = this.FormattedText.HitTestPoint(point);
-            private set;
+            return hit.TextPosition + (hit.IsTrailing ? 1 : 0);
         }
 
         public new void GotFocus()
@@ -73,9 +47,7 @@ namespace Perspex.Controls
 
         public override void Render(IDrawingContext context)
         {
-            Rect rect = new Rect(this.ActualSize);
+            base.Render(context);
-
-            context.DrawText(Brushes.Black, rect, this.FormattedText);
 
             if (this.parent.IsFocused)
             {
@@ -97,17 +69,6 @@ namespace Perspex.Controls
             this.InvalidateVisual();
         }
 
-        protected override Size MeasureOverride(Size constraint)
-        {
-            if (!string.IsNullOrEmpty(this.parent.Text))
-            {
-                this.FormattedText.Constraint = constraint;
-                return this.FormattedText.Measure();
-            }
-
-            return new Size();
-        }
-
         private void CaretTimerTick(object sender, EventArgs e)
         {
             this.caretBlink = !this.caretBlink;

Perspex.SceneGraph/Media/FontStyle.cs

@@ -0,0 +1,15 @@
+// -----------------------------------------------------------------------
+// <copyright file="FontStyle.cs" company="Steven Kirk">
+// Copyright 2014 MIT Licence. See licence.md for more information.
+// </copyright>
+// -----------------------------------------------------------------------
+
+namespace Perspex.Media
+{
+    public enum FontStyle
+    {
+        Normal,
+        Oblique,
+        Italic,
+    }
+}

Perspex.SceneGraph/Media/FormattedText.cs

@@ -6,21 +6,25 @@
 
 namespace Perspex.Media
 {
+    using System;
     using Perspex.Platform;
     using Splat;
 
-    public enum FontStyle
+    public class FormattedText : IDisposable
     {
-        Normal,
+        public FormattedText(
-        Oblique,
+            string text,
-        Italic,
+            string fontFamilyName,
-    }
+            double fontSize,
-
+            FontStyle fontStyle)
-    public class FormattedText
-    {
-        public FormattedText()
         {
-            this.PlatformImpl = Locator.Current.GetService<IFormattedTextImpl>();
+            this.Text = text;
+            this.FontFamilyName = fontFamilyName;
+            this.FontSize = fontSize;
+            this.FontStyle = fontStyle;
+
+            var platform = Locator.Current.GetService<IPlatformRenderInterface>();
+            this.PlatformImpl = platform.CreateFormattedText(text, fontFamilyName, fontSize, fontStyle);
         }
 
         public Size Constraint
@@ -31,26 +35,26 @@ namespace Perspex.Media
 
         public string FontFamilyName
         {
-            get { return this.PlatformImpl.FontFamilyName; }
+            get;
-            set { this.PlatformImpl.FontFamilyName = value; }
+            private set;
         }
 
         public double FontSize
         {
-            get { return this.PlatformImpl.FontSize; }
+            get;
-            set { this.PlatformImpl.FontSize = value; }
+            private set;
         }
 
         public FontStyle FontStyle
         {
-            get { return this.PlatformImpl.FontStyle; }
+            get;
-            set { this.PlatformImpl.FontStyle = value; }
+            private set;
         }
 
         public string Text
         {
-            get { return this.PlatformImpl.Text; }
+            get;
-            set { this.PlatformImpl.Text = value; }
+            private set;
         }
 
         public IFormattedTextImpl PlatformImpl
@@ -59,6 +63,11 @@ namespace Perspex.Media
             private set;
         }
 
+        public void Dispose()
+        {
+            this.PlatformImpl.Dispose();
+        }
+
         public TextHitTestResult HitTestPoint(Point point)
         {
             return this.PlatformImpl.HitTestPoint(point);

Perspex.SceneGraph/Media/IDrawingContext.cs

@@ -45,9 +45,9 @@ namespace Perspex.Media
         /// Draws text.
         /// </summary>
         /// <param name="foreground">The foreground brush.</param>
-        /// <param name="rect">The bounding rectangle.</param>
+        /// <param name="origin">The upper-left corner of the text.</param>
         /// <param name="text">The text.</param>
-        void DrawText(Brush foreground, Rect rect, FormattedText text);
+        void DrawText(Brush foreground, Point origin, FormattedText text);
 
         /// <summary>
         /// Draws a filled rectangle.

Perspex.SceneGraph/Perspex.SceneGraph.csproj

@@ -45,6 +45,7 @@
     <Compile Include="Media\Brushes.cs" />
     <Compile Include="Media\Color.cs" />
     <Compile Include="Media\Colors.cs" />
+    <Compile Include="Media\FontStyle.cs" />
     <Compile Include="Media\FormattedText.cs" />
     <Compile Include="Media\Geometry.cs" />
     <Compile Include="Media\IDrawingContext.cs" />

Perspex.SceneGraph/Platform/IFormattedTextImpl.cs

@@ -6,20 +6,13 @@
 
 namespace Perspex.Platform
 {
+    using System;
     using Perspex.Media;
 
-    public interface IFormattedTextImpl
+    public interface IFormattedTextImpl : IDisposable
     {
         Size Constraint { get; set; }
 
-        string FontFamilyName { get; set; }
-
-        double FontSize { get; set; }
-
-        FontStyle FontStyle { get; set; }
-
-        string Text { get; set; }
-
         TextHitTestResult HitTestPoint(Point point);
 
         Rect HitTestTextPosition(int index);

Perspex.SceneGraph/Platform/IPlatformRenderInterface.cs

@@ -6,13 +6,18 @@
 
 namespace Perspex.Platform
 {
-    using System;
+    using Perspex.Media;
-    using Perspex.Threading;
 
     public interface IPlatformRenderInterface
     {
         IBitmapImpl CreateBitmap(int width, int height);
 
+        IFormattedTextImpl CreateFormattedText(
+            string text, 
+            string fontFamily, 
+            double fontSize, 
+            FontStyle fontStyle);
+
         IStreamGeometryImpl CreateStreamGeometry();
 
         IRenderer CreateRenderer(IPlatformHandle handle, double width, double height);

Windows/Perspex.Direct2D1/Direct2D1Platform.cs

@@ -8,6 +8,7 @@ namespace Perspex.Direct2D1
 {
     using System;
     using Perspex.Direct2D1.Media;
+    using Perspex.Media;
     using Perspex.Platform;
     using Perspex.Threading;
     using Splat;
@@ -29,7 +30,6 @@ namespace Perspex.Direct2D1
             locator.Register(() => d2d1Factory, typeof(SharpDX.Direct2D1.Factory));
             locator.Register(() => dwfactory, typeof(SharpDX.DirectWrite.Factory));
             locator.Register(() => imagingFactory, typeof(SharpDX.WIC.ImagingFactory));
-            locator.Register(() => new FormattedTextImpl(), typeof(IFormattedTextImpl));
         }
 
         public IBitmapImpl CreateBitmap(int width, int height)
@@ -37,6 +37,15 @@ namespace Perspex.Direct2D1
             return new BitmapImpl(imagingFactory, width, height);
         }
 
+        public IFormattedTextImpl CreateFormattedText(
+            string text, 
+            string fontFamily, 
+            double fontSize, 
+            FontStyle fontStyle)
+        {
+            return new FormattedTextImpl(text, fontFamily, fontSize, fontStyle);
+        }
+
         public IRenderer CreateRenderer(IPlatformHandle handle, double width, double height)
         {
             if (handle.HandleDescriptor == "HWND")

Windows/Perspex.Direct2D1/Media/DrawingContext.cs

@@ -134,9 +134,9 @@ namespace Perspex.Direct2D1.Media
         /// Draws text.
         /// </summary>
         /// <param name="foreground">The foreground brush.</param>
-        /// <param name="rect">The output rectangle.</param>
+        /// <param name="origin">The upper-left corner of the text.</param>
         /// <param name="text">The text.</param>
-        public void DrawText(Perspex.Media.Brush foreground, Rect rect, FormattedText text)
+        public void DrawText(Perspex.Media.Brush foreground, Perspex.Point origin, FormattedText text)
         {
             if (!string.IsNullOrEmpty(text.Text))
             {
@@ -144,10 +144,9 @@ namespace Perspex.Direct2D1.Media
 
                 using (SharpDX.Direct2D1.SolidColorBrush brush = this.Convert(foreground))
                 {
-                    this.renderTarget.DrawText(
+                    this.renderTarget.DrawTextLayout(
-                        text.Text,
+                        origin.ToSharpDX(),
-                        impl.Layout,
+                        impl.TextLayout,
-                        this.Convert(rect),
                         brush);
                 }
             }

Windows/Perspex.Direct2D1/Media/FormattedTextImpl.cs

@@ -14,121 +14,45 @@ namespace Perspex.Direct2D1.Media
 
     public class FormattedTextImpl : IFormattedTextImpl
     {
-        private string text;
+        public FormattedTextImpl(
-
+            string text,
-        private string fontFamilyName = "Ariel";
+            string fontFamily,
-
+            double fontSize,
-        private double fontSize = 10;
+            FontStyle fontStyle)
-
-        private FontStyle fontStyle;
-
-        private DWrite.Factory factory;
-
-        private DWrite.TextLayout layout;
-
-        public FormattedTextImpl()
         {
-            this.factory = Locator.Current.GetService<DWrite.Factory>();
+            var factory = Locator.Current.GetService<DWrite.Factory>();
+
+            this.TextLayout = new DWrite.TextLayout(
+                factory,
+                text ?? string.Empty,
+                new DWrite.TextFormat(factory, fontFamily, (float)fontSize),
+                float.MaxValue,
+                float.MaxValue);
         }
 
         public Size Constraint
         {
             get
             {
-                return new Size(this.Layout.MaxWidth, this.Layout.MaxHeight);
+                return new Size(this.TextLayout.MaxWidth, this.TextLayout.MaxHeight);
-            }
-
-            set
-            {
-                this.Layout.MaxWidth = (float)value.Width;
-                this.Layout.MaxHeight = (float)value.Height;
-            }
-        }
-
-        public string FontFamilyName
-        {
-            get
-            {
-                return this.fontFamilyName;
-            }
-
-            set
-            {
-                if (this.fontFamilyName != value)
-                {
-                    this.fontFamilyName = value;
-                    this.DisposeLayout();
-                }
-            }
-        }
-
-        public double FontSize
-        {
-            get
-            {
-                return this.fontSize;
             }
 
             set
             {
-                if (this.fontSize != value)
+                this.TextLayout.MaxWidth = (float)value.Width;
-                {
+                this.TextLayout.MaxHeight = (float)value.Height;
-                    this.fontSize = value;
-                    this.DisposeLayout();
-                }
             }
         }
 
-        public FontStyle FontStyle
+        public DWrite.TextLayout TextLayout
         {
-            get
+            get;
-            {
+            private set;
-                return this.fontStyle;
-            }
-
-            set
-            {
-                if (this.fontStyle != value)
-                {
-                    this.fontStyle = value;
-                    this.DisposeLayout();
-                }
-            }
-        }
-
-        public string Text
-        {
-            get
-            {
-                return this.text;
-            }
-
-            set
-            {
-                if (this.text != value)
-                {
-                    this.text = value;
-                    this.DisposeLayout();
-                }
-            }
         }
 
-        public DWrite.TextLayout Layout
+        public void Dispose()
         {
-            get
+            this.TextLayout.Dispose();
-            {
-                if (this.layout == null)
-                {
-                    this.layout = new DWrite.TextLayout(
-                        this.factory,
-                        this.text ?? string.Empty,
-                        new DWrite.TextFormat(this.factory, this.fontFamilyName, (float)this.fontSize),
-                        float.MaxValue,
-                        float.MaxValue);
-                }
-
-                return this.layout;
-            }
         }
 
         public TextHitTestResult HitTestPoint(Point point)
@@ -136,7 +60,7 @@ namespace Perspex.Direct2D1.Media
             SharpDX.Bool isTrailingHit;
             SharpDX.Bool isInside;
 
-            DWrite.HitTestMetrics result = layout.HitTestPoint(
+            DWrite.HitTestMetrics result = this.TextLayout.HitTestPoint(
                 (float)point.X,
                 (float)point.Y,
                 out isTrailingHit,
@@ -154,7 +78,7 @@ namespace Perspex.Direct2D1.Media
             float x;
             float y;
 
-            DWrite.HitTestMetrics result = layout.HitTestTextPosition(
+            DWrite.HitTestMetrics result = this.TextLayout.HitTestTextPosition(
                 index, 
                 false, 
                 out x, 
@@ -166,17 +90,8 @@ namespace Perspex.Direct2D1.Media
         public Size Measure()
         {
             return new Size(
-                layout.Metrics.WidthIncludingTrailingWhitespace,
+                this.TextLayout.Metrics.WidthIncludingTrailingWhitespace,
-                layout.Metrics.Height);
+                this.TextLayout.Metrics.Height);
-        }
-
-        private void DisposeLayout()
-        {
-            if (this.layout != null)
-            {
-                this.layout.Dispose();
-                this.layout = null;
-            }
         }
     }
 }