IntelliJ Themes: use single Laf class for light and dark IntelliJ themes and added IntelliJTheme$ThemeLaf.properties to allow (re-)setting UI defaults before .theme.json is applied

flatlaf-core/src/main/java/com/formdev/flatlaf/FlatLaf.java

@@ -186,7 +186,13 @@ public abstract class FlatLaf
 		Object aquaMenuBarUI = useScreenMenuBar ? defaults.get( "MenuBarUI" ) : null;
 
 		initFonts( defaults );
-		UIDefaultsLoader.loadDefaultsFromProperties( getClass(), defaults );
+
+		// load defaults from properties
+		List<Class<?>> lafClassesForDefaultsLoading = getLafClassesForDefaultsLoading();
+		if( lafClassesForDefaultsLoading != null )
+			UIDefaultsLoader.loadDefaultsFromProperties( lafClassesForDefaultsLoading, defaults );
+		else
+			UIDefaultsLoader.loadDefaultsFromProperties( getClass(), defaults );
 
 		// use Aqua MenuBarUI if Mac screen menubar is enabled
 		if( useScreenMenuBar )
@@ -195,6 +201,10 @@ public abstract class FlatLaf
 		return defaults;
 	}
 
+	List<Class<?>> getLafClassesForDefaultsLoading() {
+		return null;
+	}
+
 	private void initFonts( UIDefaults defaults ) {
 		FontUIResource uiFont = null;
 

flatlaf-core/src/main/java/com/formdev/flatlaf/IntelliJTheme.java

@@ -66,10 +66,7 @@ public class IntelliJTheme
 	}
 
 	public static FlatLaf createLaf( IntelliJTheme theme ) {
-		FlatLaf laf = theme.dark
-			? new DarkLaf( theme )
-			: new LightLaf( theme );
-		return laf;
+		return new ThemeLaf( theme );
 	}
 
 	@SuppressWarnings( "unchecked" )
@@ -233,14 +230,14 @@ public class IntelliJTheme
 		checkboxKeyMapping.put( "Checkbox.Focus.Thin.Selected", "CheckBox.icon.selectedFocusedBorderColor" );
 	}
 
-	//---- class LightLaf -----------------------------------------------------
+	//---- class ThemeLaf -----------------------------------------------------
 
-	public static class LightLaf
-		extends FlatIntelliJLaf
+	public static class ThemeLaf
+		extends FlatLaf
 	{
 		private final IntelliJTheme theme;
 
-		public LightLaf( IntelliJTheme theme ) {
+		public ThemeLaf( IntelliJTheme theme ) {
 			this.theme = theme;
 		}
 
@@ -255,32 +252,8 @@ public class IntelliJTheme
 		}
 
 		@Override
-		public UIDefaults getDefaults() {
-			UIDefaults defaults = super.getDefaults();
-			theme.applyProperties( defaults );
-			return defaults;
-		}
-	}
-
-	//---- class DarkLaf ------------------------------------------------------
-
-	public static class DarkLaf
-		extends FlatDarculaLaf
-	{
-		private final IntelliJTheme theme;
-
-		public DarkLaf( IntelliJTheme theme ) {
-			this.theme = theme;
-		}
-
-		@Override
-		public String getName() {
-			return theme.name;
-		}
-
-		@Override
-		public String getDescription() {
-			return theme.name;
+		public boolean isDark() {
+			return theme.dark;
 		}
 
 		@Override
@@ -289,5 +262,15 @@ public class IntelliJTheme
 			theme.applyProperties( defaults );
 			return defaults;
 		}
+
+		@Override
+		ArrayList<Class<?>> getLafClassesForDefaultsLoading() {
+			ArrayList<Class<?>> lafClasses = new ArrayList<>();
+			lafClasses.add( FlatLaf.class );
+			lafClasses.add( theme.dark ? FlatDarkLaf.class : FlatLightLaf.class );
+			lafClasses.add( theme.dark ? FlatDarculaLaf.class : FlatIntelliJLaf.class );
+			lafClasses.add( ThemeLaf.class );
+			return lafClasses;
+		}
 	}
 }

flatlaf-core/src/main/java/com/formdev/flatlaf/UIDefaultsLoader.java

@@ -70,6 +70,10 @@ class UIDefaultsLoader
 			lafClasses.add( 0, lafClass );
 		}
 
+		loadDefaultsFromProperties( lafClasses, defaults );
+	}
+
+	static void loadDefaultsFromProperties( List<Class<?>> lafClasses, UIDefaults defaults ) {
 		try {
 			// load properties files
 			Properties properties = new Properties();

flatlaf-core/src/main/resources/com/formdev/flatlaf/IntelliJTheme$ThemeLaf.properties

@@ -0,0 +1,15 @@
+#
+# Copyright 2019 FormDev Software GmbH
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#