Merge pull request #9256 from mono/backport-pr-9228-to-release-8.4

[release-8.4] [Mac] Add initial high contrast theme support

Author: sevoku

main/src/addins/MacPlatform/MacPlatform.cs

@@ -72,6 +72,11 @@ public class MacPlatformService : PlatformService
 
 		static bool initedGlobal;
 		bool setupFail, initedApp;
+		// hold a reference on all observer objects generated by the notification center
+		// NOTE: these objects should not be actively disposed on macOS 10.11 and later, unless removed manually
+		//       not keeping a reference might cause a runtime crash when observers are added:
+		//       KVO_IS_RETAINING_ALL_OBSERVERS_OF_THIS_OBJECT_IF_IT_CRASHES_AN_OBSERVER_WAS_OVERRELEASED_OR_SMASHED
+		List<IDisposable> notificationObservers = new List<IDisposable> ();
 
 		readonly Lazy<Dictionary<string, string>> mimemap = new Lazy<Dictionary<string, string>> (LoadMimeMap);
 
@@ -317,12 +322,12 @@ public override Xwt.Toolkit LoadNativeToolkit ()
 			SwizzleNSApplication ();
 
 			var nc = NSNotificationCenter.DefaultCenter;
-			nc.AddObserver ((NSString)"AtkCocoaAccessibilityEnabled", (NSNotification) => {
+			notificationObservers.Add (nc.AddObserver ((NSString)"AtkCocoaAccessibilityEnabled", (NSNotification) => {
 				LoggingService.LogInfo ($"VoiceOver on {IdeTheme.AccessibilityEnabled}");
 				if (!IdeTheme.AccessibilityEnabled) {
 					ShowVoiceOverNotice ();
 				}
-			}, NSApplication.SharedApplication);
+			}, NSApplication.SharedApplication));
 
 			// Now that Cocoa has been initialized we can check whether the keyboard focus mode is turned on
 			// See System Preferences - Keyboard - Shortcuts - Full Keyboard Access
@@ -568,12 +573,23 @@ void InitApp (CommandManager commandManager)
 			};
 
 			PatchGtkTheme ();
-			NSNotificationCenter.DefaultCenter.AddObserver (NSCell.ControlTintChangedNotification, notif => Core.Runtime.RunInMainThread (
-				delegate {
-					Styles.LoadStyle();
-					PatchGtkTheme();
-				}));
 
+			if (MacSystemInformation.OsVersion >= MacSystemInformation.Mojave) {
+				IdeTheme.HighContrastThemeEnabled = GetIsHighContrastActive ();
+				notificationObservers.Add (NSApplication.SharedApplication.AddObserver ("effectiveAppearance", NSKeyValueObservingOptions.New, notif =>
+					Core.Runtime.RunInMainThread (() => {
+						IdeTheme.HighContrastThemeEnabled = GetIsHighContrastActive ();
+						PatchGtkTheme ();
+					})
+				));
+			} else {
+				IdeTheme.HighContrastThemeEnabled = false;
+				notificationObservers.Add (NSNotificationCenter.DefaultCenter.AddObserver (NSCell.ControlTintChangedNotification, notif => Core.Runtime.RunInMainThread (
+					delegate {
+						Styles.LoadStyle ();
+						PatchGtkTheme ();
+					})));
+			}
 
 			if (MacSystemInformation.OsVersion < MacSystemInformation.Mojave) { // the shared color panel has full automatic theme support on Mojave
 				Styles.Changed += (s, a) => {
@@ -594,6 +610,18 @@ void InitApp (CommandManager commandManager)
 			//IdeApp.Preferences.UserInterfaceTheme.Changed += (s,a) => PatchGtkTheme ();
 		}
 
+		static bool GetIsHighContrastActive ()
+		{
+			var highContrastAppearances = new string [] {
+							NSAppearance.NameAccessibilityHighContrastAqua,
+							NSAppearance.NameAccessibilityHighContrastDarkAqua,
+							NSAppearance.NameAccessibilityHighContrastVibrantDark,
+							NSAppearance.NameAccessibilityHighContrastVibrantLight,
+						};
+			// FindBestMatch will return the best matching a11y appearance or null if no high contrast appearance is in use
+			return NSApplication.SharedApplication.EffectiveAppearance.FindBestMatch (highContrastAppearances) != null;
+		}
+
 		static void UpdateColorPanelSubviewsAppearance (NSView view, NSAppearance appearance)
 		{
 			if (view.Class.Name == "NSPageableTableView")

main/src/addins/MonoDevelop.Debugger/MonoDevelop.Debugger.csproj

@@ -307,6 +307,8 @@
     <EmbeddedResource Include="icons\gutter-stack-15%402x.png" />
     <EmbeddedResource Include="icons\gutter-stack-15~dark.png" />
     <EmbeddedResource Include="icons\gutter-stack-15~dark%402x.png" />
+    <EmbeddedResource Include="icons\gutter-stack-15~contrast.png" />
+    <EmbeddedResource Include="icons\gutter-stack-15~contrast%402x.png" />
     <EmbeddedResource Include="icons\gutter-tracepoint-15.png" />
     <EmbeddedResource Include="icons\gutter-tracepoint-15%402x.png" />
     <EmbeddedResource Include="icons\gutter-tracepoint-15~dark.png" />
@@ -333,6 +335,8 @@
     <EmbeddedResource Include="icons\stack-pointer-16~disabled%402x.png" />
     <EmbeddedResource Include="icons\stack-pointer-16~dark~disabled.png" />
     <EmbeddedResource Include="icons\stack-pointer-16~dark~disabled%402x.png" />
+    <EmbeddedResource Include="icons\stack-pointer-16~contrast.png" />
+    <EmbeddedResource Include="icons\stack-pointer-16~contrast%402x.png" />
   </ItemGroup>
   <ItemGroup Condition=" '$(Configuration)' != 'DebugMac' AND '$(Configuration)' != 'ReleaseMac' ">
     <EmbeddedResource Include="icons\pause-16.png" />

main/src/addins/MonoDevelop.Debugger/icons/gutter-stack-15~contrast.png

@@ -290,6 +290,8 @@
     <EmbeddedResource Include="icons\issues-ok-16%402x.png" />
     <EmbeddedResource Include="icons\issues-ok-16~dark.png" />
     <EmbeddedResource Include="icons\issues-ok-16~dark%402x.png" />
+    <EmbeddedResource Include="icons\issues-ok-16~contrast.png" />
+    <EmbeddedResource Include="icons\issues-ok-16~contrast%402x.png" />
     <EmbeddedResource Include="icons\issues-suggestion-16.png" />
     <EmbeddedResource Include="icons\issues-suggestion-16%402x.png" />
     <EmbeddedResource Include="icons\issues-suggestion-16~dark.png" />

main/src/addins/MonoDevelop.Debugger/icons/[email protected]

@@ -129,8 +129,12 @@
     <None Remove="icons\vs-find-replace-search-16%402x.png" />
     <None Remove="icons\go-up-16.png" />
     <None Remove="icons\go-up-16%402x.png" />
+    <None Remove="icons\go-up-16~contrast.png" />
+    <None Remove="icons\go-up-16~contrast%402x.png" />
     <None Remove="icons\go-down-16.png" />
     <None Remove="icons\go-down-16%402x.png" />
+    <None Remove="icons\go-down-16~contrast.png" />
+    <None Remove="icons\go-down-16~contrast%402x.png" />
   </ItemGroup>
   <ItemGroup>
     <EmbeddedResource Include="icons\vs-find-replace-close-16.png" />
@@ -151,8 +155,12 @@
     <EmbeddedResource Include="icons\vs-find-replace-search-16%402x.png" />
     <EmbeddedResource Include="icons\go-up-16.png" />
     <EmbeddedResource Include="icons\go-up-16%402x.png" />
+    <EmbeddedResource Include="icons\go-up-16~contrast.png" />
+    <EmbeddedResource Include="icons\go-up-16~contrast%402x.png" />
     <EmbeddedResource Include="icons\go-down-16.png" />
     <EmbeddedResource Include="icons\go-down-16%402x.png" />
+    <EmbeddedResource Include="icons\go-down-16~contrast.png" />
+    <EmbeddedResource Include="icons\go-down-16~contrast%402x.png" />
   </ItemGroup>
   <Target Name="BuildTextMate" BeforeTargets="Compile">
     <MSBuild Projects="$(VSEditorCoreDirectory)src\TextMate\TMRegEx\TMRegEx.proj" Targets="Build" Properties="Configuration=$(Configuration)" />