Maui.Core Gtk enhancements

src/Core/src/Fonts/FontManager.Linux.cs

@@ -1,12 +1,148 @@
-namespace Microsoft.Maui
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using Microsoft.Maui.Graphics;
+using Pango;
+
+namespace Microsoft.Maui
 {
+
+	// see: https://developer.gnome.org/pygtk/stable/class-pangofontdescription.html
+	/*
+	  public enum Pango.Weight
+	  {
+	    Thin = 100, // 0x00000064
+	    Ultralight = 200, // 0x000000C8
+	    Light = 300, // 0x0000012C
+	    Semilight = 350, // 0x0000015E
+	    Book = 380, // 0x0000017C
+	    Normal = 400, // 0x00000190
+	    Medium = 500, // 0x000001F4
+	    Semibold = 600, // 0x00000258
+	    Bold = 700, // 0x000002BC
+	    Ultrabold = 800, // 0x00000320
+	    Heavy = 900, // 0x00000384
+	    Ultraheavy = 1000, // 0x000003E8
+	  }
+	  
+	  public enum Stretch
+	  {
+	    UltraCondensed,
+	    ExtraCondensed,
+	    Condensed,
+	    SemiCondensed,
+	    Normal,
+	    SemiExpanded,
+	    Expanded,
+	    ExtraExpanded,
+	    UltraExpanded,
+	  }
+  
+  
+    public enum Style { Normal, Oblique,  Italic  }
+  
+    public enum Variant
+  {
+    Normal,
+    SmallCaps,
+  }
+  
+    public enum Gravity
+  {
+    South,
+    East,
+    North,
+    West,
+    Auto,
+  }
+  
+	 */
+
 	public class FontManager : IFontManager
 	{
+
 		readonly IFontRegistrar _fontRegistrar;
 
+		static Pango.Context? _systemContext;
+
+		Pango.Context SystemContext => _systemContext ??= Gdk.PangoHelper.ContextGet();
+
 		public FontManager(IFontRegistrar fontRegistrar)
 		{
 			_fontRegistrar = fontRegistrar;
 		}
+
+		FontDescription? _defaultFontFamily;
+
+		public FontDescription DefaultFontFamily
+		{
+			get => _defaultFontFamily ??= GetFontFamily(default);
+		}
+
+		double? _defaultFontSize;
+
+		public double DefaultFontSize => _defaultFontSize ??= DefaultFontFamily?.GetSize() ?? 0;
+
+		public FontDescription GetFontFamily(Font font) => 
+			font == default ? SystemContext.FontDescription : font.ToFontDescription();
+
+		public double GetFontSize(Font font)
+		{
+			if (font.UseNamedSize)
+				return GetFontSize(font.NamedSize);
+
+			return font.FontSize;
+		}
+
+		public double GetFontSize(NamedSize namedSize)
+		{
+			// TODO: Hmm, maybe we need to revisit this, since we no longer support Windows Phone OR WinRT.
+			// These are values pulled from the mapped sizes on Windows Phone, WinRT has no equivalent sizes, only intents.
+
+			return namedSize switch
+			{
+				NamedSize.Default => DefaultFontSize,
+				NamedSize.Micro => 15.667,
+				NamedSize.Small => 18.667,
+				NamedSize.Medium => 22.667,
+				NamedSize.Large => 32,
+				NamedSize.Body => 14,
+				NamedSize.Caption => 12,
+				NamedSize.Header => 46,
+				NamedSize.Subtitle => 20,
+				NamedSize.Title => 24,
+				_ => throw new ArgumentOutOfRangeException(nameof(namedSize)),
+			};
+		}
+
+		private IEnumerable<(Pango.FontFamily family, Pango.FontDescription description)> GetAvailableFamilyFaces(Pango.FontFamily family)
+		{
+
+			if (family != default)
+			{
+				foreach (var face in family.Faces)
+					yield return (family, face.Describe());
+			}
+
+			yield break;
+		}
+
+		private FontDescription[] GetAvailableFontStyles()
+		{
+			var fontFamilies = SystemContext.FontMap?.Families.ToArray();
+
+			var styles = new List<FontDescription>();
+
+			if (fontFamilies != null)
+			{
+				styles.AddRange(fontFamilies.SelectMany(GetAvailableFamilyFaces).Select(font => font.description)
+				   .OrderBy(d=>d.Family));
+			}
+
+
+			return styles.ToArray();
+		}
+
 	}
+
 }

src/Core/src/Fonts/IFontManager.Linux.cs

@@ -1,7 +1,16 @@
-namespace Microsoft.Maui
+using Pango;
+
+namespace Microsoft.Maui
 {
 	public interface IFontManager
 	{
 
+		FontDescription DefaultFontFamily { get; }
+
+		double DefaultFontSize { get; }
+
+		FontDescription GetFontFamily(Font font);
+
+		double GetFontSize(Font font);
 	}
 }

src/Core/src/Handlers/ActivityIndicator/ActivityIndicatorHandler.Linux.cs

@@ -2,19 +2,23 @@
 
 namespace Microsoft.Maui.Handlers
 {
-	public partial class ActivityIndicatorHandler : ViewHandler<ICheckBox, Spinner>
+	public partial class ActivityIndicatorHandler : ViewHandler<IActivityIndicator, Spinner>
 	{
 		protected override Spinner CreateNativeView()
 		{
-			return new Spinner();
+			return new();
 		}
 
 		public static void MapIsRunning(ActivityIndicatorHandler handler, IActivityIndicator activityIndicator)
 		{
 			handler.NativeView?.UpdateIsRunning(activityIndicator);
 		}
 
-		[MissingMapper]
-		public static void MapColor(ActivityIndicatorHandler handler, IActivityIndicator activityIndicator) { }
+
+		public static void MapColor(ActivityIndicatorHandler handler, IActivityIndicator activityIndicator)
+		{
+			handler.NativeView?.SetForegroundColor(activityIndicator.Color);
+
+		}
 	}
 }

src/Core/src/Handlers/Button/ButtonHandler.Linux.cs

@@ -3,8 +3,10 @@
 
 namespace Microsoft.Maui.Handlers
 {
+
 	public partial class ButtonHandler : ViewHandler<IButton, Button>
 	{
+
 		protected override Button CreateNativeView()
 		{
 			return new Button();
@@ -29,31 +31,39 @@ public static void MapText(ButtonHandler handler, IButton button)
 			handler.NativeView?.UpdateText(button);
 		}
 
-		[MissingMapper]
-		public static void MapTextColor(ButtonHandler handler, IButton button) { }
+		public static void MapTextColor(ButtonHandler handler, IButton button)
+		{
+			handler.NativeView?.UpdateTextColor(button.TextColor);
+		}
 
 		[MissingMapper]
 		public static void MapCharacterSpacing(ButtonHandler handler, IButton button) { }
 
-		[MissingMapper]
-		public static void MapFont(ButtonHandler handler, IButton button) { }
+		public static void MapFont(ButtonHandler handler, IButton button)
+		{
+			handler.MapFont(button);
+		}
 
-		[MissingMapper]
-		public static void MapPadding(ButtonHandler handler, IButton button) { }
+		public static void MapPadding(ButtonHandler handler, IButton button)
+		{
+			handler.NativeView.WithMargin(button.Padding);
+		}
 
 		void OnButtonPressEvent(object? o, ButtonPressEventArgs args)
 		{
-			VirtualView?.Pressed();
+			InvokeEvent(() => VirtualView?.Pressed());
 		}
 
 		void OnButtonReleaseEvent(object? o, ButtonReleaseEventArgs args)
 		{
-			VirtualView?.Released();
+			InvokeEvent(() => VirtualView?.Released());
 		}
 
 		void OnButtonClicked(object? sender, EventArgs e)
 		{
-			VirtualView?.Clicked();
+			InvokeEvent(() => VirtualView?.Clicked());
 		}
+
 	}
+
 }

src/Core/src/Handlers/CheckBox/CheckBoxHandler.Linux.cs

@@ -1,17 +1,36 @@
-using Gtk;
+using System;
+using Gtk;
 
 namespace Microsoft.Maui.Handlers
 {
+
 	public partial class CheckBoxHandler : ViewHandler<ICheckBox, CheckButton>
 	{
-		protected override CheckButton CreateNativeView()
-		{
-			return new CheckButton();
-		}
+
+		protected override CheckButton CreateNativeView() => new();
 
 		public static void MapIsChecked(CheckBoxHandler handler, ICheckBox check)
 		{
 			handler.NativeView?.UpdateIsChecked(check);
 		}
+
+		protected override void ConnectHandler(CheckButton nativeView)
+		{
+			nativeView.Toggled += OnToggledEvent;
+		}
+
+		protected override void DisconnectHandler(CheckButton nativeView)
+		{
+			nativeView.Toggled -= OnToggledEvent;
+		}
+
+		protected void OnToggledEvent(object? sender, EventArgs e)
+		{
+			if (sender is CheckButton nativeView && VirtualView != null)
+				VirtualView.IsChecked = nativeView.Active;
+
+		}
+
 	}
-}
+
+}

src/Core/src/Handlers/Editor/EditorHandler.Linux.cs

@@ -2,11 +2,13 @@
 
 namespace Microsoft.Maui.Handlers
 {
+
 	public partial class EditorHandler : ViewHandler<IEditor, TextView>
 	{
+
 		protected override TextView CreateNativeView()
 		{
-			return new TextView();
+			return new();
 		}
 
 		public static void MapText(EditorHandler handler, IEditor editor)
@@ -15,27 +17,37 @@ public static void MapText(EditorHandler handler, IEditor editor)
 		}
 
 		[MissingMapper]
-		public static void MapPlaceholder(IViewHandler handler, IEditor editor) { }
+		public static void MapPlaceholder(EditorHandler handler, IEditor editor) { }
 
 		[MissingMapper]
-		public static void MapPlaceholderColor(IViewHandler handler, IEditor editor) { }
+		public static void MapPlaceholderColor(EditorHandler handler, IEditor editor) { }
 
 		[MissingMapper]
-		public static void MapCharacterSpacing(IViewHandler handler, IEditor editor) { }
+		public static void MapCharacterSpacing(EditorHandler handler, IEditor editor) { }
 
 		[MissingMapper]
-		public static void MapMaxLength(IViewHandler handler, IEditor editor) { }
+		public static void MapMaxLength(EditorHandler handler, IEditor editor) { }
 
 		[MissingMapper]
 		public static void MapIsTextPredictionEnabled(EditorHandler handler, IEditor editor) { }
 
-		[MissingMapper]
-		public static void MapFont(IViewHandler handler, IEditor editor) { }
+		public static void MapFont(EditorHandler handler, IEditor editor)
+		{
+			handler.MapFont(editor);
 
-		[MissingMapper]
-		public static void MapIsReadOnly(IViewHandler handler, IEditor editor) { }
+		}
+
+		public static void MapIsReadOnly(EditorHandler handler, IEditor editor)
+		{
+			if (handler.NativeView is { } nativeView)
+				nativeView.Editable = editor.IsReadOnly;
+		}
+
+		public static void MapTextColor(EditorHandler handler, IEditor editor)
+		{
+			handler.NativeView?.UpdateTextColor(editor.TextColor);
+		}
 
-		[MissingMapper]
-		public static void MapTextColor(EditorHandler handler, IEditor editor) { }
 	}
+
 }