cocoa: adding support of getting information IF dark theme is used

git-svn-id: trunk@61035 -

lcl/interfaces/cocoa/cocoa_extra.pas

@@ -56,10 +56,18 @@ type
     procedure setEnabled_(aenabled: ObjCBool); message 'setEnabled:';
   end;
 
+  NSAppearance = objcclass external(NSObject)
+    function name: NSString; message 'name';
+    class function currentAppearance: NSAppearance; message 'currentAppearance';
+  end;
+
   NSApplicationFix = objccategory external (NSApplication)
     procedure activateIgnoringOtherApps_(flag: ObjCBool); message 'activateIgnoringOtherApps:';
     function nextEventMatchingMask_untilDate_inMode_dequeue_(mask: NSUInteger; expiration: NSDate; mode: NSString; deqFlag: ObjCBool): NSEvent; message 'nextEventMatchingMask:untilDate:inMode:dequeue:';
     procedure postEvent_atStart_(event: NSEvent; flag: ObjCBool); message 'postEvent:atStart:';
+
+    function appearance: NSAppearance; message 'appearance'; // 10.14 (10.13)
+    function effectiveAppearance: NSAppearance; message 'effectiveAppearance'; // 10.14 (10.13)
   end;
 
   NSButtonFix = objccategory external(NSButton)
@@ -151,6 +159,8 @@ type
     procedure setHasShadow_(hasShadow_: ObjCBool); message 'setHasShadow:';
     procedure setIgnoresMouseEvents_(flag: ObjCBool); message 'setIgnoresMouseEvents:';
     {$endif}
+    // 10.14
+    function appearance: NSAppearance; message 'appearance'; // 10.14 (10.13)
   end;
 
   NSTableColumnFix = objccategory external (NSTableColumn)
@@ -198,6 +208,8 @@ const
   NSAppKitVersionNumber10_10 = 1343;
   NSAppKitVersionNumber10_11 = 1404;
   NSAppKitVersionNumber10_12 = 1504;
+  NSAppKitVersionNumber10_13 = 1561;
+  NSAppKitVersionNumber10_14 = 1641.10;
 
 
 const

lcl/interfaces/cocoa/cocoathemes.pas

@@ -22,7 +22,7 @@ uses
   LCLType, LCLProc, LCLIntf, Graphics, Themes, TmSchema,
   customdrawndrawers,
   // widgetset
-  CocoaUtils, CocoaGDIObjects;
+  CocoaUtils, CocoaGDIObjects, Cocoa_Extra;
   
 type
   { TCocoaThemeServices }
@@ -60,8 +60,93 @@ type
     function GetOption(AOption: TThemeOption): Integer; override;
   end;
 
+// "dark" is not a good reference, as Apple might add more and more themes
+function IsDarkPossible: Boolean; inline;
+
+// returns if the application appearance is set to dark
+function IsAppDark: Boolean;
+
+// returns if the window appearance is set to dark
+function IsWinDark(win: NSWindow): Boolean;
+
+// returns true, if currently drawn (Painted) UI control is in Dark theme.
+// The method would likely return FALSE outside of Paint event.
+function IsPaintDark: Boolean;
+
+// returns true, if Appear is assigned and bears name of Dark theme
+function IsAppearDark(Appear: NSAppearance): Boolean; inline;
+
+// weak-referenced NSAppearnceClass. Returns nil on any OS prior to 10.13
+function NSAppearanceClass: pobjc_class;
+
 implementation
 
+var
+  _NSAppearanceClass : pobjc_class = nil;
+  _NSAppearanceClassRead: Boolean = false;
+
+function NSAppearanceClass: pobjc_class;
+begin
+  if not _NSAppearanceClassRead then
+  begin
+    _NSAppearanceClass := objc_getClass('NSAppearance');
+    _NSAppearanceClassRead := true;
+  end;
+  Result := _NSAppearanceClass;
+end;
+
+function IsAppearDark(Appear: NSAppearance): Boolean; inline;
+begin
+  Result := Assigned(Appear)
+            and Appear.name.isEqualToString(NSSTR('NSAppearanceNameVibrantDark'))
+end;
+
+function IsDarkPossible: Boolean; inline;
+begin
+  Result := NSAppKitVersionNumber > NSAppKitVersionNumber10_12;
+end;
+
+function IsAppDark: Boolean;
+var
+  Appear: NSAppearance;
+begin
+  if not isDarkPossible then
+  begin
+    Result := false;
+    Exit;
+  end;
+  if (not NSApplication(NSApp).respondsToSelector(ObjCSelector('appearance'))) then begin
+    Result := false;
+    Exit;
+  end;
+
+  Result := IsAppearDark(NSApplication(NSApp).appearance);
+end;
+
+function IsWinDark(win: NSWindow): Boolean;
+begin
+  if not Assigned(win) or not isDarkPossible then
+  begin
+    Result := false;
+    Exit;
+  end;
+  if (not NSApplication(win).respondsToSelector(ObjCSelector('appearance'))) then begin
+    Result := false;
+    Exit;
+  end;
+
+  Result := IsAppearDark(win.appearance);
+end;
+
+function IsPaintDark: Boolean;
+var
+  cls : pobjc_class;
+begin
+  cls := NSAppearanceClass;
+  if not Assigned(cls) then Exit;
+  Result := IsAppearDark(objc_msgSend(cls, ObjCSelector('currentAppearance')));
+end;
+
 { TCocoaThemeServices }
 
 {------------------------------------------------------------------------------