Implement drawn Label control

src/GraphicsControls.Sample/MainPage.cs

@@ -1,7 +1,6 @@
 using Microsoft.Maui;
 using Microsoft.Maui.ApplicationModel;
 using Microsoft.Maui.Controls;
-using Microsoft.Maui.Graphics;
 using System;
 
 namespace GraphicsControls.Sample
@@ -202,7 +201,7 @@ IView CreateFooter()
             var footer = new Label
             {
                 FontSize = 10,
-                Text = "Microsoft Corporation 2021",
+                Text = "Microsoft Corporation 2023",
                 HorizontalOptions = LayoutOptions.Center,
                 TextColor = SampleColors.LightTextColor
             };

src/GraphicsControls/Handlers/Label/ILabelDrawable.cs

@@ -0,0 +1,8 @@
+namespace Microsoft.Maui.Graphics.Controls
+{
+    public interface ILabelDrawable : IViewDrawable<ILabel>
+    {
+        void DrawBackground(ICanvas canvas, RectF dirtyRect, ILabel view);
+        void DrawText(ICanvas canvas, RectF dirtyRect, ILabel view);
+    }
+}

src/GraphicsControls/Handlers/Label/LabelDrawable.cs

@@ -0,0 +1,74 @@
+namespace Microsoft.Maui.Graphics.Controls
+{
+    public class LabelDrawable : ViewDrawable<ILabel>, ILabelDrawable
+    {
+        public void DrawBackground(ICanvas canvas, RectF dirtyRect, ILabel label)
+        {
+            if (label.Background is null)
+                return;
+
+            canvas.SaveState();
+
+            canvas.SetFillPaint(label.Background, dirtyRect);
+
+            var x = dirtyRect.X;
+            var y = dirtyRect.Y;
+
+            var height = dirtyRect.Height;
+            var width = dirtyRect.Width;
+
+            canvas.FillRectangle(x, y, width, height);
+
+            canvas.RestoreState();
+        }
+
+        public void DrawText(ICanvas canvas, RectF dirtyRect, ILabel label)
+        {
+            canvas.SaveState();
+
+            UpdateTextColor(canvas, dirtyRect, label);
+            UpdateFont(canvas, dirtyRect, label);
+            UpdateText(canvas, dirtyRect, label);
+
+            canvas.RestoreState();
+        }
+
+        void UpdateTextColor(ICanvas canvas, RectF dirtyRect, ILabel label)
+        {
+            var textColor = label.TextColor;
+            canvas.FontColor = textColor;
+        }
+
+        void UpdateFont(ICanvas canvas, RectF dirtyRect, ILabel label)
+        {
+            if (label.Font.Weight is FontWeight.Bold)
+                canvas.Font = Font.DefaultBold;
+
+            var fontSize = (float)label.Font.Size;
+            canvas.FontSize = fontSize;
+        }
+
+        void UpdateText(ICanvas canvas, RectF dirtyRect, ILabel label)
+        {
+            var margin = label.Margin;
+            var x = (float)(dirtyRect.X + margin.Left);
+            var y = (float)(dirtyRect.Y + margin.Top);
+
+            var height = dirtyRect.Height;
+            var width = dirtyRect.Width;
+
+            string text = label.Text;
+
+            // Update CharacterSpacing
+            double characterSpacing = label.CharacterSpacing;
+            text = text.WithCharacterSpacing(characterSpacing);
+
+            canvas.DrawString(
+                text,
+                x, y, width, height,
+                label.HorizontalTextAlignment.ToHorizontalAlignment(),
+                label.VerticalTextAlignment.ToVerticalAlignment(),
+                TextFlow.ClipBounds);
+        }
+    }
+}

src/GraphicsControls/Handlers/Label/LabelHandler.cs

@@ -0,0 +1,49 @@
+using System.Linq;
+
+namespace Microsoft.Maui.Graphics.Controls
+{
+    public class LabelHandler : GraphicsControlHandler<ILabelDrawable, ILabel>
+    {
+        public LabelHandler() : base(DrawMapper, PropertyMapper)
+        {
+
+        }
+
+        public static PropertyMapper<ILabel> PropertyMapper = new PropertyMapper<ILabel>(ViewHandler.Mapper)
+        {
+            [nameof(ILabel.Text)] = ViewHandler.MapInvalidate,
+            [nameof(ILabel.TextColor)] = ViewHandler.MapInvalidate,
+            [nameof(ILabel.Font)] = ViewHandler.MapInvalidate,
+            [nameof(ILabel.CharacterSpacing)] = ViewHandler.MapInvalidate,
+            [nameof(ILabel.HorizontalTextAlignment)] = ViewHandler.MapInvalidate,
+            [nameof(ILabel.VerticalTextAlignment)] = ViewHandler.MapInvalidate,
+        };
+
+        public static DrawMapper<ILabelDrawable, ILabel> DrawMapper = new DrawMapper<ILabelDrawable, ILabel>(ViewHandler.DrawMapper)
+        {
+            ["Background"] = MapDrawBackground,
+            ["Text"] = MapDrawText
+        };
+
+        public static string[] DefaultLabelLayerDrawingOrder =
+            ViewHandler.DefaultLayerDrawingOrder.ToList().InsertAfter(new string[]
+            {
+                "Background",
+                "Text",
+            }, "Text").ToArray();
+
+        public override string[] LayerDrawingOrder() =>
+            DefaultLabelLayerDrawingOrder;
+
+        protected override ILabelDrawable CreateDrawable()
+        {
+            return new LabelDrawable();
+        }
+
+        public static void MapDrawBackground(ICanvas canvas, RectF dirtyRect, ILabelDrawable drawable, ILabel view)
+            => drawable.DrawBackground(canvas, dirtyRect, view);
+
+        public static void MapDrawText(ICanvas canvas, RectF dirtyRect, ILabelDrawable drawable, ILabel view) 
+            => drawable.DrawText(canvas, dirtyRect, view);
+    }
+}

src/GraphicsControls/Platform/TextExtensions.cs

@@ -0,0 +1,56 @@
+using System.Text;
+
+namespace Microsoft.Maui.Graphics.Controls
+{
+    public static class TextExtensions
+    {
+        public static string WithCharacterSpacing(this string input, double characterSpacing)
+        {
+            int spaces = (int)characterSpacing;
+
+            if (input.Length <= 1)
+                return input;
+
+            StringBuilder sb = new StringBuilder();
+
+            for (int i = 0; i < input.Length; i++)
+            {
+                sb.Append(input[i]);
+                if (i != input.Length - 1)
+                    sb.Append(' ', spaces);
+            }
+
+            return sb.ToString();
+        }
+
+        public static HorizontalAlignment ToHorizontalAlignment(this TextAlignment textAlignment)
+        {
+            switch (textAlignment)
+            {
+                case TextAlignment.Start:
+                    return HorizontalAlignment.Left;
+                case TextAlignment.Center:
+                    return HorizontalAlignment.Center;
+                case TextAlignment.End:
+                    return HorizontalAlignment.Right;
+                default:
+                    return HorizontalAlignment.Left;
+            }
+        }
+
+        public static VerticalAlignment ToVerticalAlignment(this TextAlignment textAlignment)
+        {
+            switch (textAlignment)
+            {
+                case TextAlignment.Start:
+                    return VerticalAlignment.Top;
+                case TextAlignment.Center:
+                    return VerticalAlignment.Center;
+                case TextAlignment.End:
+                    return VerticalAlignment.Bottom;
+                default:
+                    return VerticalAlignment.Top;
+            }
+        }
+    }
+}