added developer information to Maven POM for Maven Central publishing

The Swing fonts are not updated when the user changes system font size (System Settings > Fonts > Force Font DPI). A application restart is necessary. This is the same behavior as in native KDE applications.

tested on Kubuntu 19.04

.travis.yml

@@ -5,6 +5,7 @@ jdk:
   - openjdk8
   - openjdk9
   - openjdk11
+  - openjdk13
 
 before_cache:
   - rm -f  $HOME/.gradle/caches/modules-2/modules-2.lock
@@ -24,5 +25,5 @@ deploy:
   skip_cleanup: true # to upload artifacts created during the build
   on:
     branch: master
-    jdk: openjdk8
+    jdk: openjdk11
     tags: true

CHANGELOG.md

@@ -1,6 +1,45 @@
 FlatLaf Change Log
 ==================
 
+## 0.13
+
+- Added developer information to Maven POM for Maven Central publishing.
+
+
+## 0.12
+
+- Support Linux. (issue #2)
+- Added `Flat*Laf.install()` methods.
+- macOS: Use native screen menu bar if system property
+  `apple.laf.useScreenMenuBar` is `true`.
+- Windows: Update fonts (and scaling) when user changes Windows text size
+  (Settings > Ease of Access > Display > Make text bigger).
+
+
+## 0.11
+
+- Changed Maven groupId to `com.formdev` and artifactId to `flatlaf`.
+
+
+## 0.10
+
+- Use new chevron arrows in "Flat Light" and "Flat Dark" themes, but keep
+  triangle arrows in "Flat IntelliJ" and "Flat Darcula" themes. (issue #7)
+- Use bold font for default buttons in "Flat IntelliJ" and "Flat Darcula"
+  themes.
+- Hide label, button and tab mnemonics by default and show them only when
+  <kbd>Alt</kbd> is pressed. (issue #4)
+- If a JButton has an icon and no text, then it does not get a minimum width
+  (usually 72 pixel) and the left and right insets are same as top/bottom insets
+  so that it becomes square (if the icon is square).
+- Changed styling of default button in "Flat Light" theme (wide blue border
+  instead of blue background).
+- Added Java 9 module descriptor `module-info.class` to `flatlaf.jar` (in
+  `META-INF/versions/9`). But FlatLaf remains Java 8 compatible. (issue #1)
+- Support specifying custom scale factor in system properties `flatlaf.uiScale`
+  or `sun.java2d.uiScale`. E.g. `-Dflatlaf.uiScale=1.5`. (Java 8 only)
+
+
 ## 0.9
 
 - Initial release

README.md

@@ -4,8 +4,9 @@ FlatLaf - Flat Look and Feel
 **FlatLaf** is a modern open-source cross-platform Look and Feel for Java
 desktop applications.
 
-It is mostly "flat" (no shadows or gradients), clean, simple and elegant. It
+It looks mostly "flat" (no shadows or gradients), clean, simple and elegant.
-comes with **Light** and **Dark** themes and is made for **HiDPI** displays.
+FlatLaf comes with **Light**, **Dark**, **IntelliJ** and **Darcula** themes,
+scales on **HiDPI** displays and runs on Java 8 or newer.
 
 The look is heavily inspired by **Darcula** and **IntelliJ** themes from
 IntelliJ IDEA 2019.2+ and uses mostly the same colors and icons.
@@ -18,19 +19,22 @@ IntelliJ IDEA 2019.2+ and uses mostly the same colors and icons.
 Demo
 ----
 
-Download
+[![Download Demo](https://download.formdev.com/flatlaf/images/download-demo.svg)](https://download.formdev.com/flatlaf/flatlaf-demo-latest.jar)
-[flatlaf-demo-0.1.jar](https://download.formdev.com/flatlaf/flatlaf-demo-0.1.jar)
+
-and run it with `java -jar flatlaf-demo-0.1.jar` (or double-click it). Requires
+Run demo with `java -jar flatlaf-demo-<version>.jar` (or double-click it).
-Java 8 or newer.
+Requires Java 8 or newer.
 
 
 Download
 --------
 
-Coming soon
+[![Download](https://api.bintray.com/packages/jformdesigner/flatlaf/flatlaf/images/download.svg)](https://bintray.com/jformdesigner/flatlaf/flatlaf/_latestVersion)
+
+Download from JCenter and Maven Central is coming soon.
 
 
-License
+Documentation
--------
+-------------
 
-FlatLaf is open source licensed under the [Apache 2.0 License](LICENSE)
+For more information and documentation visit
+[FlatLaf Home](https://www.formdev.com/flatlaf/)

build.gradle.kts

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-version = "0.9"
+version = "0.13"
 
 // check required Java version
 if( JavaVersion.current() < JavaVersion.VERSION_1_8 )

flatlaf-core/build.gradle.kts

@@ -26,6 +26,18 @@ repositories {
 	jcenter()
 }
 
+if( JavaVersion.current() >= JavaVersion.VERSION_1_9 ) {
+	sourceSets {
+		create( "module-info" ) {
+			java {
+				// include "src/main/java" here to get compile errors if classes are
+				// used from other modules that are not specified in module dependencies
+				setSrcDirs( listOf( "src/main/module-info", "src/main/java" ) )
+			}
+		}
+	}
+}
+
 dependencies {
 	testImplementation( "com.miglayout:miglayout-swing:5.2" )
 	testImplementation( "com.jgoodies:jgoodies-forms:1.9.0" )
@@ -37,8 +49,26 @@ java {
 }
 
 tasks {
+	if( JavaVersion.current() >= JavaVersion.VERSION_1_9 ) {
+		named<JavaCompile>( "compileModuleInfoJava" ) {
+			sourceCompatibility = "9"
+			targetCompatibility = "9"
+		}
+	}
+	
 	jar {
 		archiveBaseName.set( "flatlaf" )
+
+		if( JavaVersion.current() >= JavaVersion.VERSION_1_9 ) {
+			manifest.attributes(
+				"Multi-Release" to "true"
+			)
+
+			into( "META-INF/versions/9" ) {
+				from( sourceSets["module-info"].output )
+				include( "module-info.class" )
+			}
+		}
 	}
 
 	javadoc {
@@ -67,8 +97,8 @@ tasks {
 publishing {
 	publications {
 		create<MavenPublication>( "maven" ) {
-			artifactId = "flatlaf-core"
+			artifactId = "flatlaf"
-			groupId = "com.formdev.flatlaf"
+			groupId = "com.formdev"
 
 			from( components["java"] )
 
@@ -87,6 +117,14 @@ publishing {
 					}
 				}
 
+				developers {
+					developer {
+						name.set( "Karl Tauber" )
+						organization.set( "FormDev Software GmbH" )
+						organizationUrl.set( "https://www.formdev.com/" )
+					}
+				}
+
 				scm {
 					url.set( "https://github.com/JFormDesigner/FlatLaf" )
 				}
@@ -103,7 +141,7 @@ bintray {
 
 	with( pkg ) {
 		repo = "flatlaf"
-		name = "flatlaf-core"
+		name = "flatlaf"
 		setLicenses( "Apache-2.0" )
 		vcsUrl = "https://github.com/JFormDesigner/FlatLaf"
 

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

@@ -24,6 +24,10 @@ package com.formdev.flatlaf;
 public class FlatDarculaLaf
 	extends FlatDarkLaf
 {
+	public static boolean install( ) {
+		return install( new FlatDarculaLaf() );
+	}
+
 	@Override
 	public String getName() {
 		return "Flat Darcula";

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

@@ -24,6 +24,10 @@ package com.formdev.flatlaf;
 public class FlatDarkLaf
 	extends FlatLaf
 {
+	public static boolean install( ) {
+		return install( new FlatDarkLaf() );
+	}
+
 	@Override
 	public String getName() {
 		return "Flat Dark";

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

@@ -24,6 +24,10 @@ package com.formdev.flatlaf;
 public class FlatIntelliJLaf
 	extends FlatLightLaf
 {
+	public static boolean install( ) {
+		return install( new FlatIntelliJLaf() );
+	}
+
 	@Override
 	public String getName() {
 		return "Flat IntelliJ";

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

@@ -16,11 +16,21 @@
 
 package com.formdev.flatlaf;
 
+import java.awt.AWTEvent;
 import java.awt.Color;
+import java.awt.Component;
+import java.awt.Container;
 import java.awt.Dimension;
+import java.awt.EventQueue;
 import java.awt.Font;
 import java.awt.Insets;
+import java.awt.KeyboardFocusManager;
 import java.awt.Toolkit;
+import java.awt.Window;
+import java.awt.event.AWTEventListener;
+import java.awt.event.KeyEvent;
+import java.beans.PropertyChangeEvent;
+import java.beans.PropertyChangeListener;
 import java.io.IOException;
 import java.io.InputStream;
 import java.util.ArrayList;
@@ -29,7 +39,14 @@ import java.util.List;
 import java.util.Map;
 import java.util.Properties;
 import java.util.function.Function;
+import javax.swing.AbstractButton;
+import javax.swing.JLabel;
+import javax.swing.JTabbedPane;
+import javax.swing.LookAndFeel;
+import javax.swing.SwingUtilities;
 import javax.swing.UIDefaults;
+import javax.swing.UIManager;
+import javax.swing.UnsupportedLookAndFeelException;
 import javax.swing.UIDefaults.LazyValue;
 import javax.swing.plaf.ColorUIResource;
 import javax.swing.plaf.DimensionUIResource;
@@ -41,6 +58,7 @@ import com.formdev.flatlaf.ui.FlatEmptyBorder;
 import com.formdev.flatlaf.ui.FlatLineBorder;
 import com.formdev.flatlaf.util.ScaledNumber;
 import com.formdev.flatlaf.util.SystemInfo;
+import com.formdev.flatlaf.util.UIScale;
 
 /**
  * The base class for all Flat LaFs.
@@ -57,6 +75,22 @@ public abstract class FlatLaf
 
 	private BasicLookAndFeel base;
 
+	private String desktopPropertyName;
+	private PropertyChangeListener desktopPropertyListener;
+
+	private AWTEventListener mnemonicListener;
+	private static boolean altKeyPressed;
+
+	public static boolean install( LookAndFeel newLookAndFeel ) {
+		try {
+		    UIManager.setLookAndFeel( newLookAndFeel );
+		    return true;
+		} catch( Exception ex ) {
+		    System.err.println( "Failed to initialize look and feel " + newLookAndFeel.getClass().getName() );
+		    return false;
+		}
+	}
+
 	@Override
 	public String getID() {
 		return getName();
@@ -77,10 +111,48 @@ public abstract class FlatLaf
 		getBase().initialize();
 
 		super.initialize();
+
+		// add mnemonic listener
+		mnemonicListener = e -> {
+			if( e instanceof KeyEvent && ((KeyEvent)e).getKeyCode() == KeyEvent.VK_ALT )
+				altKeyChanged( e.getID() == KeyEvent.KEY_PRESSED );
+		};
+		Toolkit.getDefaultToolkit().addAWTEventListener( mnemonicListener, AWTEvent.KEY_EVENT_MASK );
+
+		// listen to desktop property changes to update UI if system font or scaling changes
+		if( SystemInfo.IS_WINDOWS ) {
+			// Windows 10 allows increasing font size independent of scaling:
+			//   Settings > Ease of Access > Display > Make text bigger (100% - 225%)
+			desktopPropertyName = "win.messagebox.font";
+		} else if( SystemInfo.IS_LINUX ) {
+			// Linux/Gnome allows extra scaling and larger text:
+			//   Settings > Devices > Displays > Scale (100% or 200%)
+			//   Settings > Universal access > Large Text (off or on, 125%)
+			desktopPropertyName = "gnome.Xft/DPI";
+		}
+		if( desktopPropertyName != null ) {
+			desktopPropertyListener = e -> {
+				reSetLookAndFeel();
+			};
+			Toolkit.getDefaultToolkit().addPropertyChangeListener( desktopPropertyName, desktopPropertyListener );
+		}
 	}
 
 	@Override
 	public void uninitialize() {
+		// remove desktop property listener
+		if( desktopPropertyListener != null ) {
+			Toolkit.getDefaultToolkit().removePropertyChangeListener( desktopPropertyName, desktopPropertyListener );
+			desktopPropertyName = null;
+			desktopPropertyListener = null;
+		}
+
+		// remove mnemonic listener
+		if( mnemonicListener != null ) {
+			Toolkit.getDefaultToolkit().removeAWTEventListener( mnemonicListener );
+			mnemonicListener = null;
+		}
+
 		if( base != null )
 			base.uninitialize();
 
@@ -128,9 +200,17 @@ public abstract class FlatLaf
 		defaults.put( "Spinner.disabledBackground", control );
 		defaults.put( "Spinner.disabledForeground", control );
 
+		// remember MenuBarUI from Mac Aqua LaF if Mac screen menubar is enabled
+		boolean useScreenMenuBar = SystemInfo.IS_MAC && "true".equals( System.getProperty( "apple.laf.useScreenMenuBar" ) );
+		Object aquaMenuBarUI = useScreenMenuBar ? defaults.get( "MenuBarUI" ) : null;
+
 		initFonts( defaults );
 		loadDefaultsFromProperties( defaults );
 
+		// use Aqua MenuBarUI if Mac screen menubar is enabled
+		if( useScreenMenuBar )
+			defaults.put( "MenuBarUI", aquaMenuBarUI );
+
 		return defaults;
 	}
 
@@ -153,12 +233,15 @@ public abstract class FlatLaf
 			uiFont = (font instanceof FontUIResource) ? (FontUIResource) font : new FontUIResource( font );
 
 		} else if( SystemInfo.IS_LINUX ) {
-			System.err.println( "WARNING: FlatLaf is not yet tested on Linux!" );
+			Font font = LinuxFontPolicy.getFont();
+			uiFont = (font instanceof FontUIResource) ? (FontUIResource) font : new FontUIResource( font );
 		}
 
 		if( uiFont == null )
 			return;
 
+		uiFont = UIScale.applyCustomScaleFactor( uiFont );
+
 		// override fonts
 		for( Object key : defaults.keySet() ) {
 			if( key instanceof String && ((String)key).endsWith( ".font" ) )
@@ -285,15 +368,15 @@ public abstract class FlatLaf
 			key.endsWith( "Margins" ) || key.endsWith( "Insets" ) )
 			return parseInsets( value );
 
-		// size
-		if( key.endsWith( "Size" ) && !key.equals( "SplitPane.dividerSize" ))
-			return parseSize( value );
-
 		// scaled number
 		ScaledNumber scaledNumber = parseScaledNumber( key, value );
 		if( scaledNumber != null )
 			return scaledNumber;
 
+		// size
+		if( key.endsWith( "Size" ) && !key.equals( "SplitPane.dividerSize" ))
+			return parseSize( value );
+
 		// width, height
 		if( key.endsWith( "Width" ) || key.endsWith( "Height" ) )
 			return parseInteger( value, true );
@@ -400,7 +483,9 @@ public abstract class FlatLaf
 	}
 
 	private ScaledNumber parseScaledNumber( String key, String value ) {
-		if( !key.equals( "OptionPane.buttonMinimumWidth" ) )
+		if( !key.equals( "OptionPane.buttonMinimumWidth" ) &&
+			!key.equals( "SplitPane.oneTouchButtonSize" ) &&
+			!key.equals( "SplitPane.oneTouchButtonOffset" ) )
 		  return null; // not supported
 
 		try {
@@ -424,4 +509,90 @@ public abstract class FlatLaf
 
 		return strs;
 	}
+
+	private static void reSetLookAndFeel() {
+		EventQueue.invokeLater( () -> {
+			try {
+				// re-set current LaF
+				LookAndFeel lookAndFeel = UIManager.getLookAndFeel();
+				UIManager.setLookAndFeel( lookAndFeel );
+
+				// must fire property change events ourself because old and new LaF are the same
+				PropertyChangeEvent e = new PropertyChangeEvent( UIManager.class, "lookAndFeel", lookAndFeel, lookAndFeel );
+				for( PropertyChangeListener l : UIManager.getPropertyChangeListeners() )
+					l.propertyChange( e );
+
+				// update UI
+				updateUI();
+			} catch( UnsupportedLookAndFeelException ex ) {
+				ex.printStackTrace();
+			}
+		} );
+	}
+
+	/**
+	 * Update UI of all application windows.
+	 * Invoke after changing LaF.
+	 */
+	public static void updateUI() {
+		for( Window w : Window.getWindows() )
+			SwingUtilities.updateComponentTreeUI( w );
+	}
+
+	public static boolean isShowMnemonics() {
+		return altKeyPressed || !UIManager.getBoolean( "Component.hideMnemonics" );
+	}
+
+	private static void altKeyChanged( boolean pressed ) {
+		if( pressed == altKeyPressed )
+			return;
+
+		altKeyPressed = pressed;
+
+		// check whether it is necessary to repaint
+		if( !UIManager.getBoolean( "Component.hideMnemonics" ) )
+			return;
+
+		// get focus owner
+		Component focusOwner = KeyboardFocusManager.getCurrentKeyboardFocusManager().getFocusOwner();
+		if( focusOwner == null )
+			return;
+
+		// get focused window
+		Window window = SwingUtilities.windowForComponent( focusOwner );
+		if( window == null )
+			return;
+
+		// repaint components with mnemonics in focused window
+		repaintMnemonics( window );
+	}
+
+	private static void repaintMnemonics( Container container ) {
+		for( Component c : container.getComponents() ) {
+			if( hasMnemonic( c ) )
+				c.repaint();
+
+			if( c instanceof Container )
+				repaintMnemonics( (Container) c );
+		}
+	}
+
+	private static boolean hasMnemonic( Component c ) {
+		if( c instanceof JLabel && ((JLabel)c).getDisplayedMnemonicIndex() >= 0 )
+			return true;
+
+		if( c instanceof AbstractButton && ((AbstractButton)c).getDisplayedMnemonicIndex() >= 0 )
+			return true;
+
+		if( c instanceof JTabbedPane ) {
+			JTabbedPane tabPane = (JTabbedPane) c;
+			int tabCount = tabPane.getTabCount();
+			for( int i = 0; i < tabCount; i++ ) {
+				if( tabPane.getDisplayedMnemonicIndexAt( i ) >= 0 )
+					return true;
+			}
+		}
+
+		return false;
+	}
 }

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

@@ -24,6 +24,10 @@ package com.formdev.flatlaf;
 public class FlatLightLaf
 	extends FlatLaf
 {
+	public static boolean install( ) {
+		return install( new FlatLightLaf() );
+	}
+
 	@Override
 	public String getName() {
 		return "Flat Light";

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

@@ -0,0 +1,248 @@
+/*
+ * 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.
+ */
+
+package com.formdev.flatlaf;
+
+import java.awt.Font;
+import java.awt.GraphicsEnvironment;
+import java.awt.Toolkit;
+import java.io.BufferedReader;
+import java.io.File;
+import java.io.FileReader;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import java.util.StringTokenizer;
+import javax.swing.text.StyleContext;
+import com.formdev.flatlaf.util.SystemInfo;
+
+/**
+ * @author Karl Tauber
+ */
+class LinuxFontPolicy
+{
+	static Font getFont() {
+		return SystemInfo.IS_KDE ? getKDEFont() : getGnomeFont();
+	}
+
+	/**
+	 * Gets the default font for Gnome.
+	 */
+	private static Font getGnomeFont() {
+		// see class com.sun.java.swing.plaf.gtk.PangoFonts background information
+
+		Object fontName = Toolkit.getDefaultToolkit().getDesktopProperty( "gnome.Gtk/FontName" );
+		if( !(fontName instanceof String) )
+			fontName = "sans 10";
+
+		String family = "";
+		int style = Font.PLAIN;
+		int size = 10;
+
+		StringTokenizer st = new StringTokenizer( (String) fontName );
+		while( st.hasMoreTokens() ) {
+			String word = st.nextToken();
+
+			if( word.equalsIgnoreCase( "italic" ) )
+				style |= Font.ITALIC;
+			else if( word.equalsIgnoreCase( "bold" ) )
+				style |= Font.BOLD;
+			else if( Character.isDigit( word.charAt( 0 ) ) ) {
+				try {
+					size = Integer.parseInt( word );
+				} catch( NumberFormatException ex ) {
+					// ignore
+				}
+			} else
+				family = family.isEmpty() ? word : (family + ' ' + word);
+		}
+
+		// scale font size
+		double dsize = size * getGnomeFontScale();
+		size = (int) (dsize + 0.5);
+		if( size < 1 )
+			size = 1;
+
+		// handle logical font names
+		String logicalFamily = mapFcName( family.toLowerCase() );
+		if( logicalFamily != null )
+			family = logicalFamily;
+
+		return createFont( family, style, size, dsize );
+	}
+
+	private static Font createFont( String family, int style, int size, double dsize ) {
+		// using StyleContext.getFont() here because it uses
+		// sun.font.FontUtilities.getCompositeFontUIResource()
+		Font font = new StyleContext().getFont( family, style, size );
+
+		// set font size in floating points
+		font = font.deriveFont( style, (float) dsize );
+
+		return font;
+	}
+
+	private static double getGnomeFontScale() {
+		// see class com.sun.java.swing.plaf.gtk.PangoFonts background information
+
+		Object value = Toolkit.getDefaultToolkit().getDesktopProperty( "gnome.Xft/DPI" );
+		if( value instanceof Integer ) {
+			int dpi = ((Integer)value).intValue() / 1024;
+			if( dpi == -1 )
+				dpi = 96;
+			if( dpi < 50 )
+				dpi = 50;
+			return dpi / 72.0;
+		} else {
+			return GraphicsEnvironment.getLocalGraphicsEnvironment()
+				.getDefaultScreenDevice().getDefaultConfiguration()
+				.getNormalizingTransform().getScaleY();
+		}
+	}
+
+	/**
+	 * map GTK/fontconfig names to equivalent JDK logical font name
+	 */
+	private static String mapFcName( String name ) {
+		switch( name ) {
+			case "sans":		return "sansserif";
+			case "sans-serif":	return "sansserif";
+			case "serif":		return "serif";
+			case "monospace":	return "monospaced";
+		}
+		return null;
+	}
+
+	/**
+	 * Gets the default font for KDE for KDE configuration files.
+	 *
+	 * The Swing fonts are not updated when the user changes system font size
+	 * (System Settings > Fonts > Force Font DPI). A application restart is necessary.
+	 * This is the same behavior as in native KDE applications.
+	 *
+	 * The "display scale factor" (kdeglobals: [KScreen] > ScaleFactor) is not used
+	 * KDE also does not use it to calculate font size. Only forceFontDPI is used by KDE.
+	 * If user changes "display scale factor" (System Settings > Display and Monitors >
+	 * Displays > Scale Display), the forceFontDPI is also changed to reflect the scale factor.
+	 */
+	private static Font getKDEFont() {
+		List<String> kdeglobals = readConfig( "kdeglobals" );
+		List<String> kcmfonts = readConfig( "kcmfonts" );
+
+		String generalFont = getConfigEntry( kdeglobals, "General", "font" );
+		String forceFontDPI = getConfigEntry( kcmfonts, "General", "forceFontDPI" );
+
+		String family = "sansserif";
+		int style = Font.PLAIN;
+		int size = 10;
+
+		if( generalFont != null ) {
+			List<String> strs = FlatLaf.split( generalFont, ',' );
+			try {
+				family = strs.get( 0 );
+				size = Integer.parseInt( strs.get( 1 ) );
+				if( "75".equals( strs.get( 4 ) ) )
+					style |= Font.BOLD;
+				if( "1".equals( strs.get( 5 ) ) )
+					style |= Font.ITALIC;
+			} catch( RuntimeException ex ) {
+				ex.printStackTrace();
+			}
+		}
+
+		// font dpi
+		int dpi = 96;
+		if( forceFontDPI != null ) {
+			try {
+				dpi = Integer.parseInt( forceFontDPI );
+				if( dpi <= 0 )
+					dpi = 96;
+				if( dpi < 50 )
+					dpi = 50;
+			} catch( NumberFormatException ex ) {
+				ex.printStackTrace();
+			}
+		}
+
+		// scale font size
+		double fontScale = dpi / 72.0;
+		double dsize = size * fontScale;
+		size = (int) (dsize + 0.5);
+		if( size < 1 )
+			size = 1;
+
+		return createFont( family, style, size, dsize );
+	}
+
+	private static List<String> readConfig( String filename ) {
+		File userHome = new File( System.getProperty( "user.home" ) );
+
+		// search for config file
+		String[] configDirs = {
+			".config", // KDE 5
+			".kde4/share/config", // KDE 4
+			".kde/share/config"// KDE 3
+		};
+		File file = null;
+		for( String configDir : configDirs ) {
+			file = new File( userHome, configDir + "/" + filename );
+			if( file.isFile() )
+				break;
+		}
+		if( !file.isFile() )
+			return Collections.emptyList();
+
+		// read config file
+		ArrayList<String> lines = new ArrayList<>( 200 );
+		try( BufferedReader reader = new BufferedReader( new FileReader( file ) ) ) {
+			String line = null;
+			while( (line = reader.readLine()) != null )
+				lines.add( line );
+		} catch( IOException ex ) {
+			ex.printStackTrace();
+		}
+		return lines;
+	}
+
+	private static String getConfigEntry( List<String> config, String group, String key ) {
+		int groupLength = group.length();
+		int keyLength = key.length();
+		boolean inGroup = false;
+		for( String line : config ) {
+			if( !inGroup ) {
+				if( line.length() >= groupLength + 2 &&
+					line.charAt( 0 ) == '[' &&
+					line.charAt( groupLength + 1 ) == ']' &&
+					line.indexOf( group ) == 1 )
+				{
+					inGroup = true;
+				}
+			} else {
+				if( line.startsWith( "[" ) )
+					return null;
+
+				if( line.length() >= keyLength + 2 &&
+					line.charAt( keyLength ) == '=' &&
+					line.startsWith( key ) )
+				{
+					return line.substring( keyLength + 1 );
+				}
+			}
+		}
+		return null;
+	}
+}

flatlaf-core/src/main/java/com/formdev/flatlaf/icons/FlatMenuArrowIcon.java

@@ -16,9 +16,11 @@
 
 package com.formdev.flatlaf.icons;
 
+import java.awt.BasicStroke;
 import java.awt.Color;
 import java.awt.Component;
 import java.awt.Graphics2D;
+import java.awt.geom.Path2D;
 import javax.swing.JMenu;
 import javax.swing.UIManager;
 import com.formdev.flatlaf.ui.FlatUIUtils;
@@ -26,6 +28,7 @@ import com.formdev.flatlaf.ui.FlatUIUtils;
 /**
  * "arrow" icon for {@link javax.swing.JMenu}.
  *
+ * @uiDefault Component.arrowType				String	triangle (default) or chevron
  * @uiDefault Menu.icon.arrowColor				Color
  * @uiDefault Menu.icon.disabledArrowColor		Color
  * @uiDefault Menu.selectionForeground			Color
@@ -35,12 +38,13 @@ import com.formdev.flatlaf.ui.FlatUIUtils;
 public class FlatMenuArrowIcon
 	extends FlatAbstractIcon
 {
+	protected final boolean chevron = "chevron".equals( UIManager.getString( "Component.arrowType" ) );
 	protected final Color arrowColor = UIManager.getColor( "Menu.icon.arrowColor" );
 	protected final Color disabledArrowColor = UIManager.getColor( "Menu.icon.disabledArrowColor" );
 	protected final Color selectionForeground = UIManager.getColor( "Menu.selectionForeground" );
 
 	public FlatMenuArrowIcon() {
-		super( 5, 10, null );
+		super( 6, 10, null );
 	}
 
 	@Override
@@ -49,8 +53,16 @@ public class FlatMenuArrowIcon
 			g.rotate( Math.toRadians( 180 ), width / 2., height / 2. );
 
 		g.setColor( getArrowColor( c ) );
+		if( chevron ) {
+			// chevron arrow
+			Path2D path = FlatUIUtils.createPath( false, 1,1, 5,5, 1,9 );
+			g.setStroke( new BasicStroke( 1f ) );
+			g.draw( path );
+		} else {
+			// triangle arrow
 			g.fill( FlatUIUtils.createPath( 0,0.5, 0,9.5, 5,5 ) );
 		}
+	}
 
 	private Color getArrowColor( Component c ) {
 		if( c instanceof JMenu && ((JMenu)c).isSelected() )

flatlaf-core/src/main/java/com/formdev/flatlaf/icons/FlatTreeCollapsedIcon.java

@@ -16,6 +16,7 @@
 
 package com.formdev.flatlaf.icons;
 
+import java.awt.Color;
 import java.awt.Component;
 import java.awt.Graphics2D;
 import javax.swing.UIManager;
@@ -24,6 +25,7 @@ import com.formdev.flatlaf.ui.FlatUIUtils;
 /**
  * "collapsed" icon for {@link javax.swing.JTree}.
  *
+ * @uiDefault Component.arrowType				String	triangle (default) or chevron
  * @uiDefault Tree.icon.collapsedColor			Color
  *
  * @author Karl Tauber
@@ -31,15 +33,32 @@ import com.formdev.flatlaf.ui.FlatUIUtils;
 public class FlatTreeCollapsedIcon
 	extends FlatAbstractIcon
 {
+	private final boolean chevron;
+
 	public FlatTreeCollapsedIcon() {
-		super( 11, 11, UIManager.getColor( "Tree.icon.collapsedColor" ) );
+		this( UIManager.getColor( "Tree.icon.collapsedColor" ) );
+	}
+
+	FlatTreeCollapsedIcon( Color color ) {
+		super( 11, 11, color );
+		chevron = "chevron".equals( UIManager.getString( "Component.arrowType" ) );
 	}
 
 	@Override
 	protected void paintIcon( Component c, Graphics2D g ) {
-		if( !c.getComponentOrientation().isLeftToRight() )
+		rotate( c, g );
-			g.rotate( Math.toRadians( 180 ), width / 2., height / 2. );
 
+		if( chevron ) {
+			// chevron arrow
+			g.fill( FlatUIUtils.createPath( 3,1, 3,2.5, 6,5.5, 3,8.5, 3,10, 4.5,10, 9,5.5, 4.5,1 ) );
+		} else {
+			// triangle arrow
 			g.fill( FlatUIUtils.createPath( 2,1, 2,10, 10,5.5 ) );
 		}
 	}
+
+	void rotate( Component c, Graphics2D g ) {
+		if( !c.getComponentOrientation().isLeftToRight() )
+			g.rotate( Math.toRadians( 180 ), width / 2., height / 2. );
+	}
+}

flatlaf-core/src/main/java/com/formdev/flatlaf/icons/FlatTreeExpandedIcon.java

@@ -19,7 +19,6 @@ package com.formdev.flatlaf.icons;
 import java.awt.Component;
 import java.awt.Graphics2D;
 import javax.swing.UIManager;
-import com.formdev.flatlaf.ui.FlatUIUtils;
 
 /**
  * "expanded" icon for {@link javax.swing.JTree}.
@@ -29,14 +28,14 @@ import com.formdev.flatlaf.ui.FlatUIUtils;
  * @author Karl Tauber
  */
 public class FlatTreeExpandedIcon
-	extends FlatAbstractIcon
+	extends FlatTreeCollapsedIcon
 {
 	public FlatTreeExpandedIcon() {
-		super( 11, 11, UIManager.getColor( "Tree.icon.expandedColor" ) );
+		super( UIManager.getColor( "Tree.icon.expandedColor" ) );
 	}
 
 	@Override
-	protected void paintIcon( Component c, Graphics2D g ) {
+	void rotate( Component c, Graphics2D g ) {
-		g.fill( FlatUIUtils.createPath( 1,2, 10,2, 5.5,10 ) );
+		g.rotate( Math.toRadians( 90 ), width / 2., height / 2. );
 	}
 }

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatArrowButton.java

@@ -17,6 +17,7 @@
 package com.formdev.flatlaf.ui;
 
 import static com.formdev.flatlaf.util.UIScale.scale;
+import java.awt.BasicStroke;
 import java.awt.Color;
 import java.awt.Dimension;
 import java.awt.Graphics;
@@ -37,6 +38,7 @@ public class FlatArrowButton
 	extends BasicArrowButton
 	implements UIResource
 {
+	private final boolean chevron;
 	private final Color foreground;
 	private final Color disabledForeground;
 	private final Color hoverForeground;
@@ -47,11 +49,12 @@ public class FlatArrowButton
 
 	private boolean hover;
 
-	public FlatArrowButton( int direction, Color foreground, Color disabledForeground,
+	public FlatArrowButton( int direction, String type, Color foreground, Color disabledForeground,
 		Color hoverForeground, Color hoverBackground )
 	{
 		super( direction, Color.WHITE, Color.WHITE, Color.WHITE, Color.WHITE );
 
+		this.chevron = "chevron".equals( type );
 		this.foreground = foreground;
 		this.disabledForeground = disabledForeground;
 		this.hoverForeground = hoverForeground;
@@ -77,6 +80,10 @@ public class FlatArrowButton
 		}
 	}
 
+	protected boolean isHover() {
+		return hover;
+	}
+
 	public int getXOffset() {
 		return xOffset;
 	}
@@ -113,7 +120,7 @@ public class FlatArrowButton
 		boolean enabled = isEnabled();
 
 		// paint hover background
-		if( enabled && hover && hoverBackground != null ) {
+		if( enabled && isHover() && hoverBackground != null ) {
 			g.setColor( hoverBackground );
 			g.fillRect( 0, 0, width, height );
 		}
@@ -121,26 +128,41 @@ public class FlatArrowButton
 		int direction = getDirection();
 		boolean vert = (direction == NORTH || direction == SOUTH);
 
-		int w = scale( 9 );
+		int w = scale( chevron ? 8 : 9 );
-		int h = scale( 5 );
+		int h = scale( chevron ? 4 : 5 );
-		int x = Math.round( (width - (vert ? w : h)) / 2f + scale( (float) xOffset ) );
+		int rw = vert ? w : h;
-		int y = Math.round( (height - (vert ? h : w)) / 2f + scale( (float) yOffset ) );
+		int rh = vert ? h : w;
+		int x = Math.round( (width - rw) / 2f + scale( (float) xOffset ) );
+		int y = Math.round( (height - rh) / 2f + scale( (float) yOffset ) );
+
+		// optimization for small chevron arrows (e.g. OneTouchButtons in SplitPane)
+		if( x + rw >= width && x > 0 )
+			x--;
+		if( y + rh >= height && y > 0 )
+			y--;
 
 		// paint arrow
 		g.setColor( enabled
-			? (hover && hoverForeground != null ? hoverForeground : foreground)
+			? (isHover() && hoverForeground != null ? hoverForeground : foreground)
 			: disabledForeground );
 		g.translate( x, y );
-		g2.fill( createArrowShape( direction, w, h ) );
+		Shape arrowShape = createArrowShape( direction, chevron, w, h );
+		if( chevron ) {
+			g2.setStroke( new BasicStroke( scale( 1f ) ) );
+			g2.draw( arrowShape );
+		} else {
+			// triangle
+			g2.fill( arrowShape );
+		}
 		g.translate( -x, -y );
 	}
 
-	public static Shape createArrowShape( int direction, int w, int h ) {
+	public static Shape createArrowShape( int direction, boolean chevron, int w, int h ) {
 		switch( direction ) {
-			case NORTH:	return FlatUIUtils.createPath( 0,h, w,h, (w / 2f),0 );
+			case NORTH:	return FlatUIUtils.createPath( !chevron, 0,h, (w / 2f),0, w,h );
-			case SOUTH:	return FlatUIUtils.createPath( 0,0, w,0, (w / 2f),h );
+			case SOUTH:	return FlatUIUtils.createPath( !chevron, 0,0, (w / 2f),h, w,0 );
-			case WEST:	return FlatUIUtils.createPath( h,0, h,w, 0,(w / 2f) );
+			case WEST:	return FlatUIUtils.createPath( !chevron, h,0, 0,(w / 2f), h,w );
-			case EAST:	return FlatUIUtils.createPath( 0,0, 0,w, h,(w / 2f) );
+			case EAST:	return FlatUIUtils.createPath( !chevron, 0,0, h,(w / 2f), 0,w );
 			default:	return new Path2D.Float();
 		}
 	}

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatBorder.java

@@ -48,6 +48,7 @@ import javax.swing.text.JTextComponent;
  * {@link FlatUIUtils#paintParentBackground} to paint the empty space correctly.
  *
  * @uiDefault Component.focusWidth			int
+ * @uiDefault Component.innerFocusWidth		int
  * @uiDefault Component.focusColor			Color
  * @uiDefault Component.borderColor			Color
  * @uiDefault Component.disabledBorderColor	Color
@@ -59,6 +60,7 @@ public class FlatBorder
 	extends BasicBorders.MarginBorder
 {
 	protected final int focusWidth = UIManager.getInt( "Component.focusWidth" );
+	protected final int innerFocusWidth = UIManager.getInt( "Component.innerFocusWidth" );
 	protected final Color focusColor = UIManager.getColor( "Component.focusColor" );
 	protected final Color borderColor = UIManager.getColor( "Component.borderColor" );
 	protected final Color disabledBorderColor = UIManager.getColor( "Component.disabledBorderColor" );
@@ -71,16 +73,17 @@ public class FlatBorder
 			FlatUIUtils.setRenderingHints( g2 );
 
 			float focusWidth = getFocusWidth();
-			float lineWidth = getLineWidth();
+			float borderWidth = getBorderWidth( c );
 			float arc = getArc();
 
 			if( isFocused( c ) ) {
 				g2.setColor( getFocusColor( c ) );
-				FlatUIUtils.paintOutlineBorder( g2, x, y, width, height, focusWidth, lineWidth, arc );
+				FlatUIUtils.paintOutlineBorder( g2, x, y, width, height, focusWidth,
+					getLineWidth() + scale( (float) innerFocusWidth ), arc );
 			}
 
 			g2.setPaint( getBorderColor( c ) );
-			FlatUIUtils.drawRoundRectangle( g2, x, y, width, height, focusWidth, lineWidth, arc );
+			FlatUIUtils.drawRoundRectangle( g2, x, y, width, height, focusWidth, borderWidth, arc );
 		} finally {
 			g2.dispose();
 		}
@@ -149,6 +152,10 @@ public class FlatBorder
 		return scale( 1f );
 	}
 
+	protected float getBorderWidth( Component c ) {
+		return getLineWidth();
+	}
+
 	protected float getArc() {
 		return 0;
 	}

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatButtonBorder.java

@@ -20,8 +20,11 @@ import static com.formdev.flatlaf.util.UIScale.scale;
 import java.awt.Color;
 import java.awt.Component;
 import java.awt.Graphics;
+import java.awt.Insets;
 import java.awt.Paint;
+import javax.swing.JButton;
 import javax.swing.UIManager;
+import javax.swing.plaf.UIResource;
 
 /**
  * Border for {@link javax.swing.JButton}.
@@ -34,6 +37,7 @@ import javax.swing.UIManager;
  * @uiDefault Button.default.hoverBorderColor	Color	optional
  * @uiDefault Button.default.focusedBorderColor	Color
  * @uiDefault Button.default.focusColor			Color
+ * @uiDefault Button.default.borderWidth		int
  * @uiDefault Button.arc						int
  *
  * @author Karl Tauber
@@ -49,6 +53,7 @@ public class FlatButtonBorder
 	protected final Color defaultHoverBorderColor = UIManager.getColor( "Button.default.hoverBorderColor" );
 	protected final Color defaultFocusedBorderColor = UIManager.getColor( "Button.default.focusedBorderColor" );
 	protected final Color defaultFocusColor = UIManager.getColor( "Button.default.focusColor" );
+	protected final int defaultBorderWidth = UIManager.getInt( "Button.default.borderWidth" );
 	protected final int arc = UIManager.getInt( "Button.arc" );
 
 	@Override
@@ -73,6 +78,22 @@ public class FlatButtonBorder
 			null );
 	}
 
+	@Override
+	public Insets getBorderInsets( Component c, Insets insets ) {
+		insets = super.getBorderInsets( c, insets );
+
+		// use smaller left and right insets for icon-only buttons (so that they are square)
+		if( FlatButtonUI.isIconOnlyButton( c ) && ((JButton)c).getMargin() instanceof UIResource )
+			insets.left = insets.right = Math.min( insets.top, insets.bottom );
+
+		return insets;
+	}
+
+	@Override
+	protected float getBorderWidth( Component c ) {
+		return FlatButtonUI.isDefaultButton( c ) ? scale( (float) defaultBorderWidth ) : super.getBorderWidth( c );
+	}
+
 	@Override
 	protected float getArc() {
 		return scale( (float) arc );

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatButtonUI.java

@@ -21,6 +21,7 @@ import static com.formdev.flatlaf.util.UIScale.scale;
 import java.awt.Color;
 import java.awt.Component;
 import java.awt.Dimension;
+import java.awt.Font;
 import java.awt.FontMetrics;
 import java.awt.Graphics;
 import java.awt.Graphics2D;
@@ -35,7 +36,9 @@ import javax.swing.LookAndFeel;
 import javax.swing.UIManager;
 import javax.swing.border.Border;
 import javax.swing.plaf.ComponentUI;
+import javax.swing.plaf.UIResource;
 import javax.swing.plaf.basic.BasicButtonUI;
+import com.formdev.flatlaf.FlatLaf;
 
 /**
  * Provides the Flat LaF UI delegate for {@link javax.swing.JButton}.
@@ -55,6 +58,7 @@ import javax.swing.plaf.basic.BasicButtonUI;
  * @uiDefault Button.default.focusedBackground	Color	optional
  * @uiDefault Button.default.hoverBackground	Color	optional
  * @uiDefault Button.default.pressedBackground	Color	optional
+ * @uiDefault Button.default.boldText			boolean
  * @uiDefault Button.toolbar.hoverBackground	Color
  * @uiDefault Button.toolbar.pressedBackground	Color
  *
@@ -78,6 +82,7 @@ public class FlatButtonUI
 	protected Color defaultFocusedBackground;
 	protected Color defaultHoverBackground;
 	protected Color defaultPressedBackground;
+	protected boolean defaultBoldText;
 
 	protected Color toolbarHoverBackground;
 	protected Color toolbarPressedBackground;
@@ -116,6 +121,7 @@ public class FlatButtonUI
 			defaultFocusedBackground = UIManager.getColor( "Button.default.focusedBackground" );
 			defaultHoverBackground = UIManager.getColor( "Button.default.hoverBackground" );
 			defaultPressedBackground = UIManager.getColor( "Button.default.pressedBackground" );
+			defaultBoldText = UIManager.getBoolean( "Button.default.boldText" );
 
 			toolbarHoverBackground = UIManager.getColor( prefix + "toolbar.hoverBackground" );
 			toolbarPressedBackground = UIManager.getColor( prefix + "toolbar.pressedBackground" );
@@ -146,6 +152,13 @@ public class FlatButtonUI
 		return c instanceof JButton && ((JButton)c).isDefaultButton();
 	}
 
+	static boolean isIconOnlyButton( Component c ) {
+		String text;
+		return c instanceof JButton &&
+			((JButton)c).getIcon() != null &&
+			((text = ((JButton)c).getText()) == null || text.isEmpty());
+	}
+
 	static boolean isHelpButton( Component c ) {
 		return c instanceof JButton && clientPropertyEquals( (JButton) c, BUTTON_TYPE, BUTTON_TYPE_HELP );
 	}
@@ -191,12 +204,23 @@ public class FlatButtonUI
 		if( isHelpButton( b ) )
 			return;
 
+		if( defaultBoldText && isDefaultButton( b ) && b.getFont() instanceof UIResource ) {
+			Font boldFont = g.getFont().deriveFont( Font.BOLD );
+			g.setFont( boldFont );
+
+			int boldWidth = b.getFontMetrics( boldFont ).stringWidth( text );
+			if( boldWidth > textRect.width ) {
+				textRect.x -= (boldWidth - textRect.width) / 2;
+				textRect.width = boldWidth;
+			}
+		}
+
 		paintText( g, b, textRect, text, b.isEnabled() ? getForeground( b ) : disabledText );
 	}
 
 	static void paintText( Graphics g, AbstractButton b, Rectangle textRect, String text, Color foreground ) {
 		FontMetrics fm = b.getFontMetrics( b.getFont() );
-		int mnemonicIndex = b.getDisplayedMnemonicIndex();
+		int mnemonicIndex = FlatLaf.isShowMnemonics() ? b.getDisplayedMnemonicIndex() : -1;
 
 		g.setColor( foreground );
 		FlatUIUtils.drawStringUnderlineCharAt( b, g, text, mnemonicIndex,
@@ -259,8 +283,11 @@ public class FlatButtonUI
 			return new Dimension( helpButtonIcon.getIconWidth(), helpButtonIcon.getIconHeight() );
 
 		Dimension prefSize = super.getPreferredSize( c );
-		if( !isToolBarButton( c ) )
+
+		// apply minimum width, if not in toolbar and not a icon-only button
+		if( !isToolBarButton( c ) && !isIconOnlyButton( c ) )
 			prefSize.width = Math.max( prefSize.width, scale( minimumWidth + (focusWidth * 2) ) );
+
 		return prefSize;
 	}
 }

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatComboBoxUI.java

@@ -29,6 +29,7 @@ import java.awt.Rectangle;
 import java.awt.Shape;
 import java.awt.event.FocusEvent;
 import java.awt.event.FocusListener;
+import java.awt.event.MouseListener;
 import java.awt.geom.Rectangle2D;
 import java.beans.PropertyChangeEvent;
 import java.beans.PropertyChangeListener;
@@ -57,6 +58,7 @@ import com.formdev.flatlaf.util.UIScale;
  *
  * @uiDefault Component.focusWidth				int
  * @uiDefault Component.arc						int
+ * @uiDefault Component.arrowType				String	triangle (default) or chevron
  * @uiDefault Component.borderColor				Color
  * @uiDefault Component.disabledBorderColor		Color
  * @uiDefault ComboBox.disabledBackground		Color
@@ -74,6 +76,7 @@ public class FlatComboBoxUI
 {
 	protected int focusWidth;
 	protected int arc;
+	protected String arrowType;
 	protected Color borderColor;
 	protected Color disabledBorderColor;
 
@@ -86,16 +89,42 @@ public class FlatComboBoxUI
 	protected Color buttonDisabledArrowColor;
 	protected Color buttonHoverArrowColor;
 
+	private MouseListener hoverListener;
+	private boolean hover;
+
 	public static ComponentUI createUI( JComponent c ) {
 		return new FlatComboBoxUI();
 	}
 
+	@Override
+	protected void installListeners() {
+		super.installListeners();
+
+		hoverListener = new FlatUIUtils.HoverListener( null, h -> {
+			if( !comboBox.isEditable() ) {
+				hover = h;
+				if( arrowButton != null )
+					arrowButton.repaint();
+			}
+		} );
+		comboBox.addMouseListener( hoverListener );
+	}
+
+	@Override
+	protected void uninstallListeners() {
+		super.uninstallListeners();
+
+		comboBox.removeMouseListener( hoverListener );
+		hoverListener = null;
+	}
+
 	@Override
 	protected void installDefaults() {
 		super.installDefaults();
 
 		focusWidth = UIManager.getInt( "Component.focusWidth" );
 		arc = UIManager.getInt( "Component.arc" );
+		arrowType = UIManager.getString( "Component.arrowType" );
 		borderColor = UIManager.getColor( "Component.borderColor" );
 		disabledBorderColor = UIManager.getColor( "Component.disabledBorderColor" );
 
@@ -224,8 +253,14 @@ public class FlatComboBoxUI
 
 	@Override
 	protected JButton createArrowButton() {
-		return new FlatArrowButton( SwingConstants.SOUTH, buttonArrowColor,
+		return new FlatArrowButton( SwingConstants.SOUTH, arrowType, buttonArrowColor,
-			buttonDisabledArrowColor, buttonHoverArrowColor, null );
+			buttonDisabledArrowColor, buttonHoverArrowColor, null )
+		{
+			@Override
+			protected boolean isHover() {
+				return super.isHover() || (!comboBox.isEditable() ? hover : false);
+			}
+		};
 	}
 
 	@Override

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatLabelUI.java

@@ -27,6 +27,7 @@ import javax.swing.SwingUtilities;
 import javax.swing.UIManager;
 import javax.swing.plaf.ComponentUI;
 import javax.swing.plaf.basic.BasicLabelUI;
+import com.formdev.flatlaf.FlatLaf;
 import com.formdev.flatlaf.util.UIScale;
 
 /**
@@ -71,9 +72,16 @@ public class FlatLabelUI
 		defaults_initialized = false;
 	}
 
+	@Override
+	protected void paintEnabledText( JLabel l, Graphics g, String s, int textX, int textY ) {
+		int mnemIndex = FlatLaf.isShowMnemonics() ? l.getDisplayedMnemonicIndex() : -1;
+		g.setColor( l.getForeground() );
+		FlatUIUtils.drawStringUnderlineCharAt( l, g, s, mnemIndex, textX, textY );
+	}
+
 	@Override
 	protected void paintDisabledText( JLabel l, Graphics g, String s, int textX, int textY ) {
-		int mnemIndex = l.getDisplayedMnemonicIndex();
+		int mnemIndex = FlatLaf.isShowMnemonics() ? l.getDisplayedMnemonicIndex() : -1;
 		g.setColor( disabledForeground );
 		FlatUIUtils.drawStringUnderlineCharAt( l, g, s, mnemIndex, textX, textY );
 	}

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatSpinnerUI.java

@@ -48,6 +48,7 @@ import javax.swing.plaf.basic.BasicSpinnerUI;
  * @uiDefault Component.focusWidth				int
  * @uiDefault Component.arc						int
  * @uiDefault Component.minimumWidth			int
+ * @uiDefault Component.arrowType				String	triangle (default) or chevron
  * @uiDefault Component.borderColor				Color
  * @uiDefault Component.disabledBorderColor		Color
  * @uiDefault Spinner.disabledBackground		Color
@@ -68,6 +69,7 @@ public class FlatSpinnerUI
 	protected int focusWidth;
 	protected int arc;
 	protected int minimumWidth;
+	protected String arrowType;
 	protected Color borderColor;
 	protected Color disabledBorderColor;
 	protected Color disabledBackground;
@@ -89,6 +91,7 @@ public class FlatSpinnerUI
 		focusWidth = UIManager.getInt( "Component.focusWidth" );
 		arc = UIManager.getInt( "Component.arc" );
 		minimumWidth = UIManager.getInt( "Component.minimumWidth" );
+		arrowType = UIManager.getString( "Component.arrowType" );
 		borderColor = UIManager.getColor( "Component.borderColor" );
 		disabledBorderColor = UIManager.getColor( "Component.disabledBorderColor" );
 		disabledBackground = UIManager.getColor( "Spinner.disabledBackground" );
@@ -209,7 +212,7 @@ public class FlatSpinnerUI
 	}
 
 	private Component createArrowButton( int direction, String name ) {
-		FlatArrowButton button = new FlatArrowButton( direction, buttonArrowColor,
+		FlatArrowButton button = new FlatArrowButton( direction, arrowType, buttonArrowColor,
 			buttonDisabledArrowColor, buttonHoverArrowColor, null );
 		button.setName( name );
 		button.setYOffset( (direction == SwingConstants.NORTH) ? 1 : -1 );

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatSplitPaneUI.java

@@ -31,6 +31,7 @@ import com.formdev.flatlaf.util.UIScale;
 /**
  * Provides the Flat LaF UI delegate for {@link javax.swing.JSplitPane}.
  *
+ * @uiDefault Component.arrowType						String	triangle (default) or chevron
  * @uiDefault SplitPane.background						Color
  * @uiDefault SplitPane.foreground						Color unused
  * @uiDefault SplitPane.dividerSize						int
@@ -46,6 +47,7 @@ import com.formdev.flatlaf.util.UIScale;
 public class FlatSplitPaneUI
 	extends BasicSplitPaneUI
 {
+	protected String arrowType;
 	private Boolean continuousLayout;
 	private Color oneTouchArrowColor;
 	private Color oneTouchHoverArrowColor;
@@ -56,6 +58,8 @@ public class FlatSplitPaneUI
 
 	@Override
 	protected void installDefaults() {
+		arrowType = UIManager.getString( "Component.arrowType" );
+
 		// get one-touch colors before invoking super.installDefaults() because they are
 		// used in there on LaF switching
 		oneTouchArrowColor = UIManager.getColor( "SplitPaneDivider.oneTouchArrowColor" );
@@ -108,7 +112,7 @@ public class FlatSplitPaneUI
 			private final boolean left;
 
 			public FlatOneTouchButton( boolean left ) {
-				super( SwingConstants.NORTH, oneTouchArrowColor, null, oneTouchHoverArrowColor, null );
+				super( SwingConstants.NORTH, arrowType, oneTouchArrowColor, null, oneTouchHoverArrowColor, null );
 				setCursor( Cursor.getPredefinedCursor( Cursor.DEFAULT_CURSOR ) );
 
 				this.left = left;

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatTabbedPaneUI.java

@@ -33,12 +33,14 @@ import javax.swing.plaf.ComponentUI;
 import javax.swing.plaf.UIResource;
 import javax.swing.plaf.basic.BasicTabbedPaneUI;
 import javax.swing.text.View;
+import com.formdev.flatlaf.FlatLaf;
 
 /**
  * Provides the Flat LaF UI delegate for {@link javax.swing.JTabbedPane}.
  *
  * @clientProperty JTabbedPane.hasFullBorder			boolean
  *
+ * @uiDefault Component.arrowType						String	triangle (default) or chevron
  * @uiDefault TabbedPane.font							Font
  * @uiDefault TabbedPane.background						Color
  * @uiDefault TabbedPane.foreground						Color
@@ -144,7 +146,8 @@ public class FlatTabbedPaneUI
 	@Override
 	protected JButton createScrollButton( int direction ) {
 		// this method is invoked before installDefaults(), so we can not use color fields here
-		return new FlatArrowButton( direction, UIManager.getColor("TabbedPane.shadow"),
+		return new FlatArrowButton( direction, UIManager.getString( "Component.arrowType" ),
+			UIManager.getColor( "TabbedPane.shadow" ),
 			UIManager.getColor( "TabbedPane.disabledForeground" ), null,
 			UIManager.getColor( "TabbedPane.hoverColor" ) );
 	}
@@ -261,7 +264,7 @@ public class FlatTabbedPaneUI
 		} else
 			color = disabledForeground;
 
-		int mnemIndex = tabPane.getDisplayedMnemonicIndexAt( tabIndex );
+		int mnemIndex = FlatLaf.isShowMnemonics() ? tabPane.getDisplayedMnemonicIndexAt( tabIndex ) : -1;
 
 		g.setColor( color );
 		FlatUIUtils.drawStringUnderlineCharAt( tabPane, g, title, mnemIndex,

flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatUIUtils.java

@@ -181,10 +181,15 @@ public class FlatUIUtils
 	}
 
 	public static Path2D createPath( double... points ) {
+		return createPath( true, points );
+	}
+
+	public static Path2D createPath( boolean close, double... points ) {
 		Path2D path = new Path2D.Float();
 		path.moveTo( points[0], points[1] );
 		for( int i = 2; i < points.length; i += 2 )
 			path.lineTo( points[i], points[i + 1] );
+		if( close )
 			path.closePath();
 		return path;
 	}

flatlaf-core/src/main/java/com/formdev/flatlaf/util/SystemInfo.java

@@ -40,6 +40,9 @@ public class SystemInfo
 	// Java VMs
 	public static final boolean IS_JETBRAINS_JVM;
 
+	// UI toolkits
+	public static final boolean IS_KDE;
+
 	static {
 		// platforms
 		String osName = System.getProperty( "os.name" ).toLowerCase( Locale.ENGLISH );
@@ -58,6 +61,9 @@ public class SystemInfo
 		// Java VMs
 		IS_JETBRAINS_JVM = System.getProperty( "java.vm.vendor", "Unknown" )
 			.toLowerCase( Locale.ENGLISH ).contains( "jetbrains" );
+
+		// UI toolkits
+		IS_KDE = (IS_LINUX && System.getenv( "KDE_FULL_SESSION" ) != null);
 	}
 
 	private static long scanVersion( String version ) {

flatlaf-core/src/main/java/com/formdev/flatlaf/util/UIScale.java

@@ -28,6 +28,7 @@ import java.lang.reflect.Method;
 import javax.swing.LookAndFeel;
 import javax.swing.UIManager;
 import javax.swing.plaf.DimensionUIResource;
+import javax.swing.plaf.FontUIResource;
 import javax.swing.plaf.InsetsUIResource;
 import javax.swing.plaf.UIResource;
 
@@ -47,8 +48,7 @@ import javax.swing.plaf.UIResource;
  *
  * 2) user scaling mode
  *
- * This mode is for Java 8 compatibility and can be removed when changing minimum
+ * This mode is mainly for Java 8 compatibility, but is also used on Linux.
- * required Java version to 9.
  * The user scale factor is computed based on the used font.
  * The JRE does not scale anything.
  * So we have to invoke {@link #scale(float)} where necessary.
@@ -65,7 +65,7 @@ public class UIScale
 
 	private static Boolean jreHiDPI;
 
-	private static boolean isJreHiDPIEnabled() {
+	public static boolean isSystemScalingEnabled() {
 		if( jreHiDPI != null )
 			return jreHiDPI;
 
@@ -93,19 +93,24 @@ public class UIScale
 	}
 
 	public static double getSystemScaleFactor( Graphics2D g ) {
-		return isJreHiDPIEnabled() ? g.getDeviceConfiguration().getDefaultTransform().getScaleX() : 1;
+		return isSystemScalingEnabled() ? g.getDeviceConfiguration().getDefaultTransform().getScaleX() : 1;
 	}
 
 	public static double getSystemScaleFactor( GraphicsConfiguration gc ) {
-		return isJreHiDPIEnabled() ? gc.getDefaultTransform().getScaleX() : 1;
+		return isSystemScalingEnabled() ? gc.getDefaultTransform().getScaleX() : 1;
 	}
 
 	//---- user scaling (Java 8) ----------------------------------------------
 
 	private static float scaleFactor = 1;
+	private static boolean initialized;
 
-	static {
+	private static void initialize() {
-		if( isEnabled() ) {
+		if( initialized )
+			return;
+		initialized = true;
+
+		if( isUserScalingEnabled() ) {
 			// listener to update scale factor if LaF changed or if Label.font changed
 			// (e.g. option "Override default fonts" in IntelliJ IDEA)
 			PropertyChangeListener listener = new PropertyChangeListener() {
@@ -129,7 +134,7 @@ public class UIScale
 	}
 
 	private static void updateScaleFactor() {
-		if( !isEnabled() )
+		if( !isUserScalingEnabled() )
 			return;
 
 		// use font size to calculate scale factor (instead of DPI)
@@ -138,6 +143,10 @@ public class UIScale
 		// (e.g. can avoid large icons with small text)
 		Font font = UIManager.getFont( "Label.font" );
 
+		setUserScaleFactor( computeScaleFactor( font ) );
+	}
+
+	private static float computeScaleFactor( Font font ) {
 		// default font size
 		float fontSizeDivider = 12f;
 
@@ -148,15 +157,15 @@ public class UIScale
 			if( "Tahoma".equals( font.getFamily() ) )
 				fontSizeDivider = 11f;
 		} else if( SystemInfo.IS_LINUX ) {
-			// default font size for Unity and Gnome is 15
+			// default font size for Unity and Gnome is 15 and for KDE it is 13
-			fontSizeDivider = 15f;
+			fontSizeDivider = SystemInfo.IS_KDE ? 13f : 15f;
 		}
 
-		setUserScaleFactor( font.getSize() / fontSizeDivider );
+		return font.getSize() / fontSizeDivider;
 	}
 
-	private static boolean isEnabled() {
+	private static boolean isUserScalingEnabled() {
-		if( isJreHiDPIEnabled() )
+		if( isSystemScalingEnabled() && !SystemInfo.IS_LINUX )
 			return false; // disable user scaling if JRE scales
 
 		// same as in IntelliJ IDEA
@@ -164,7 +173,58 @@ public class UIScale
 		return (hidpi != null) ? Boolean.parseBoolean( hidpi ) : true;
 	}
 
+	/**
+	 * Applies a custom scale factor given in system properties "flatlaf.uiScale"
+	 * or "sun.java2d.uiScale" to the given font.
+	 */
+	public static FontUIResource applyCustomScaleFactor( FontUIResource font ) {
+		if( UIScale.isSystemScalingEnabled() )
+			return font;
+
+		String uiScale = System.getProperty( "flatlaf.uiScale" );
+		if( uiScale == null )
+			uiScale = System.getProperty( "sun.java2d.uiScale" );
+
+		float scaleFactor = parseScaleFactor( uiScale );
+		if( scaleFactor <= 0 )
+			return font;
+
+		float fontScaleFactor = computeScaleFactor( font );
+		if( scaleFactor == fontScaleFactor )
+			return font;
+
+		int newFontSize = Math.round( (font.getSize() / fontScaleFactor) * scaleFactor );
+		return new FontUIResource( font.getFamily(), font.getStyle(), newFontSize );
+	}
+
+	/**
+	 * Similar to sun.java2d.SunGraphicsEnvironment.getScaleFactor(String)
+	 */
+	private static float parseScaleFactor( String s ) {
+		if( s == null )
+			return -1;
+
+		float units = 1;
+		if( s.endsWith( "x" ) )
+			s = s.substring( 0, s.length() - 1 );
+		else if( s.endsWith( "dpi" ) ) {
+			units = 96;
+			s = s.substring( 0, s.length() - 3 );
+		} else if( s.endsWith( "%" ) ) {
+			units = 100;
+			s = s.substring( 0, s.length() - 1 );
+		}
+
+		try {
+			float scale = Float.parseFloat( s );
+			return scale > 0 ? scale / units : -1;
+		} catch( NumberFormatException ex ) {
+			return -1;
+		}
+	}
+
 	public static float getUserScaleFactor() {
+		initialize();
 		return scaleFactor;
 	}
 
@@ -181,10 +241,12 @@ public class UIScale
 	}
 
 	public static float scale( float value ) {
+		initialize();
 		return (scaleFactor == 1) ? value : (value * scaleFactor);
 	}
 
 	public static int scale( int value ) {
+		initialize();
 		return (scaleFactor == 1) ? value : Math.round( value * scaleFactor );
 	}
 
@@ -192,23 +254,28 @@ public class UIScale
 	 * Similar as scale(int) but always "rounds down".
 	 */
 	public static int scale2( int value ) {
+		initialize();
 		return (scaleFactor == 1) ? value : (int) (value * scaleFactor);
 	}
 
 	public static float unscale( float value ) {
+		initialize();
 		return (scaleFactor == 1f) ? value : (value / scaleFactor);
 	}
 
 	public static int unscale( int value ) {
+		initialize();
 		return (scaleFactor == 1f) ? value : Math.round( value / scaleFactor );
 	}
 
 	public static void scaleGraphics( Graphics2D g ) {
+		initialize();
 		if( scaleFactor != 1f )
 			g.scale( scaleFactor, scaleFactor );
 	}
 
 	public static Dimension scale( Dimension dimension ) {
+		initialize();
 		return (dimension == null || scaleFactor == 1f)
 			? dimension
 			: (dimension instanceof UIResource
@@ -217,6 +284,7 @@ public class UIScale
 	}
 
 	public static Insets scale( Insets insets ) {
+		initialize();
 		return (insets == null || scaleFactor == 1f)
 			? insets
 			: (insets instanceof UIResource

flatlaf-core/src/main/module-info/module-info.java

@@ -0,0 +1,27 @@
+/*
+ * 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.
+ */
+
+/**
+ * @author Karl Tauber
+ */
+module com.formdev.flatlaf {
+	requires java.desktop;
+
+	exports com.formdev.flatlaf;
+	exports com.formdev.flatlaf.icons;
+	exports com.formdev.flatlaf.ui;
+	exports com.formdev.flatlaf.util;
+}

flatlaf-core/src/main/resources/com/formdev/flatlaf/FlatDarculaLaf.properties

@@ -18,9 +18,16 @@
 # which is licensed under the Apache 2.0 license. Copyright 2000-2019 JetBrains s.r.o.
 # See: https://github.com/JetBrains/intellij-community/
 
+#---- Button ----
+
+Button.default.boldText=true
+
+
 #---- Component ----
 
 Component.focusWidth=2
+Component.innerFocusWidth=0
+Component.arrowType=triangle
 
 
 #---- RadioButton ----

flatlaf-core/src/main/resources/com/formdev/flatlaf/FlatDarkLaf.properties

@@ -79,6 +79,7 @@ Button.default.borderColor=4c708c
 Button.default.hoverBorderColor=537699
 Button.default.focusedBorderColor=537699
 Button.default.focusColor=43688c
+Button.default.boldText=true
 
 Button.toolbar.hoverBackground=4c5052
 Button.toolbar.pressedBackground=555a5d

flatlaf-core/src/main/resources/com/formdev/flatlaf/FlatIntelliJLaf.properties

@@ -22,6 +22,17 @@
 
 Button.focusedBackground=null
 
+Button.default.background=4A86C7
+Button.default.foreground=f0f0f0
+Button.default.focusedBackground=null
+Button.default.hoverBackground=5B91CC
+Button.default.pressedBackground=6E9ED2
+Button.default.borderColor=3167ad
+Button.default.hoverBorderColor=a8cef6
+Button.default.focusedBorderColor=a8cef6
+Button.default.focusColor=97c3f3
+Button.default.boldText=true
+
 
 #---- CheckBox ----
 
@@ -37,6 +48,8 @@ CheckBox.icon.selectedPressedBackground=72A1D4
 #---- Component ----
 
 Component.focusWidth=2
+Component.innerFocusWidth=0
+Component.arrowType=triangle
 
 
 #---- RadioButton ----

flatlaf-core/src/main/resources/com/formdev/flatlaf/FlatLaf.properties

@@ -70,6 +70,8 @@ Button.iconTextGap=4
 Button.rollover=true
 Button.defaultButtonFollowsFocus=false
 
+Button.default.borderWidth=1
+
 
 #---- CheckBox ----
 
@@ -103,8 +105,11 @@ ComboBox.padding=2,6,2,6
 #---- Component ----
 
 Component.focusWidth=0
+Component.innerFocusWidth=0
 Component.arc=5
 Component.minimumWidth=64
+Component.arrowType=chevron
+Component.hideMnemonics=true
 
 
 #---- EditorPane ----
@@ -306,6 +311,8 @@ SplitPane.dividerSize=5
 SplitPane.continuousLayout=true
 SplitPane.border=null
 SplitPane.centerOneTouchButtons=true
+SplitPane.oneTouchButtonSize=6
+SplitPane.oneTouchButtonOffset=2
 
 SplitPaneDivider.border=null
 SplitPaneDivider.oneTouchArrowColor=@@ComboBox.buttonArrowColor

flatlaf-core/src/main/resources/com/formdev/flatlaf/FlatLightLaf.properties

@@ -72,14 +72,16 @@ Button.disabledBorderColor=cfcfcf
 Button.focusedBorderColor=87afda
 Button.hoverBorderColor=@@Button.focusedBorderColor
 
-Button.default.background=4A86C7
+Button.default.background=@@Button.background
-Button.default.foreground=f0f0f0
+Button.default.foreground=@foreground
-Button.default.hoverBackground=5B91CC
+Button.default.focusedBackground=@@Button.focusedBackground
-Button.default.pressedBackground=6E9ED2
+Button.default.hoverBackground=@@Button.hoverBackground
-Button.default.borderColor=3167ad
+Button.default.pressedBackground=@@Button.pressedBackground
-Button.default.hoverBorderColor=a8cef6
+Button.default.borderColor=4D89C9
-Button.default.focusedBorderColor=a8cef6
+Button.default.hoverBorderColor=@@Button.hoverBorderColor
-Button.default.focusColor=97c3f3
+Button.default.focusedBorderColor=@@Button.focusedBorderColor
+Button.default.focusColor=@@Component.focusColor
+Button.default.borderWidth=2
 
 Button.toolbar.hoverBackground=dfdfdf
 Button.toolbar.pressedBackground=d8d8d8

flatlaf-core/src/test/java/com/formdev/flatlaf/FlatComponentsTest.java

@@ -55,6 +55,7 @@ public class FlatComponentsTest
 		FlatComponentsTest.TestDefaultButton button5 = new FlatComponentsTest.TestDefaultButton();
 		JButton button3 = new JButton();
 		JButton button12 = new JButton();
+		JButton button13 = new JButton();
 		JLabel toggleButtonLabel = new JLabel();
 		JToggleButton toggleButton1 = new JToggleButton();
 		JToggleButton toggleButton2 = new JToggleButton();
@@ -246,6 +247,10 @@ public class FlatComponentsTest
 		button12.setEnabled(false);
 		add(button12, "cell 4 1");
 
+		//---- button13 ----
+		button13.setIcon(UIManager.getIcon("Tree.closedIcon"));
+		add(button13, "cell 5 1");
+
 		//---- toggleButtonLabel ----
 		toggleButtonLabel.setText("JToggleButton:");
 		add(toggleButtonLabel, "cell 0 2");

flatlaf-core/src/test/java/com/formdev/flatlaf/FlatComponentsTest.jfd

@@ -76,6 +76,12 @@ new FormModel {
 			}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
 				"value": "cell 4 1"
 			} )
+			add( new FormComponent( "javax.swing.JButton" ) {
+				name: "button13"
+				"icon": new com.jformdesigner.model.SwingIcon( 2, "Tree.closedIcon" )
+			}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
+				"value": "cell 5 1"
+			} )
 			add( new FormComponent( "javax.swing.JLabel" ) {
 				name: "toggleButtonLabel"
 				"text": "JToggleButton:"

flatlaf-core/src/test/java/com/formdev/flatlaf/FlatInspector.java

@@ -23,6 +23,7 @@ import java.awt.Dimension;
 import java.awt.EventQueue;
 import java.awt.Font;
 import java.awt.Graphics;
+import java.awt.Graphics2D;
 import java.awt.Insets;
 import java.awt.Rectangle;
 import java.awt.event.MouseEvent;
@@ -41,6 +42,7 @@ import javax.swing.border.LineBorder;
 import javax.swing.plaf.UIResource;
 import javax.swing.text.JTextComponent;
 import com.formdev.flatlaf.ui.FlatToolTipUI;
+import com.formdev.flatlaf.ui.FlatUIUtils;
 import com.formdev.flatlaf.util.UIScale;
 
 /**
@@ -103,7 +105,7 @@ public class FlatInspector
 	private void inspect( int x, int y ) {
 		Container contentPane = rootPane.getContentPane();
 		Component c = SwingUtilities.getDeepestComponentAt( contentPane, x, y );
-		if( c == contentPane || c.getParent() == contentPane )
+		if( c == contentPane || (c != null && c.getParent() == contentPane) )
 			c = null;
 
 		if( c == lastComponent )
@@ -137,6 +139,12 @@ public class FlatInspector
 				g.setColor( getBackground() );
 				g.fillRect( 0, 0, getWidth(), getHeight() );
 			}
+
+			@Override
+			protected void paintBorder( Graphics g ) {
+				FlatUIUtils.setRenderingHints( (Graphics2D) g );
+				super.paintBorder( g );
+			}
 		};
 		c.setBackground( new Color( 255, 0, 0, 32 ) );
 		c.setBorder( new LineBorder( Color.red ) );

flatlaf-core/src/test/java/com/formdev/flatlaf/FlatTestFrame.java

@@ -17,13 +17,21 @@
 package com.formdev.flatlaf;
 
 import java.awt.*;
+import java.awt.event.ComponentAdapter;
+import java.awt.event.ComponentEvent;
 import java.awt.event.KeyEvent;
+import java.awt.event.WindowAdapter;
+import java.awt.event.WindowEvent;
+import java.beans.PropertyChangeEvent;
+import java.beans.PropertyChangeListener;
 import java.util.prefs.Preferences;
 import javax.swing.*;
 import javax.swing.plaf.ColorUIResource;
 import javax.swing.plaf.metal.MetalLookAndFeel;
 import javax.swing.plaf.nimbus.NimbusLookAndFeel;
+import com.formdev.flatlaf.ui.FlatUIUtils;
 import com.formdev.flatlaf.util.SystemInfo;
+import com.formdev.flatlaf.util.UIScale;
 import net.miginfocom.swing.*;
 
 /**
@@ -34,47 +42,53 @@ public class FlatTestFrame
 {
 	private static final String PREFS_ROOT_PATH = "/flatlaf-test";
 	private static final String KEY_LAF = "laf";
+	private static final String KEY_SCALE_FACTOR = "scaleFactor";
 
+	private final String title;
 	private JComponent content;
 	private FlatInspector inspector;
 
 	public static FlatTestFrame create( String[] args, String title ) {
+		Preferences prefs = Preferences.userRoot().node( PREFS_ROOT_PATH );
+
+		// set scale factor
+		if( System.getProperty( "flatlaf.uiScale", System.getProperty( "sun.java2d.uiScale" ) ) == null ) {
+			String scaleFactor = prefs.get( KEY_SCALE_FACTOR, null );
+			if( scaleFactor != null )
+				System.setProperty( "flatlaf.uiScale", scaleFactor );
+		}
+
 		// set look and feel
 		try {
 			if( args.length > 0 )
 				UIManager.setLookAndFeel( args[0] );
 			else {
-				String lafClassName = Preferences.userRoot().node( PREFS_ROOT_PATH )
+				String lafClassName = prefs.get( KEY_LAF, FlatLightLaf.class.getName() );
-					.get( KEY_LAF, FlatLightLaf.class.getName() );
 				UIManager.setLookAndFeel( lafClassName );
 			}
 		} catch( Exception ex ) {
 			ex.printStackTrace();
 
 			// fallback
-			try {
+			FlatLightLaf.install();
-				UIManager.setLookAndFeel( new FlatLightLaf() );
-			} catch( Exception ex2 ) {
-				ex2.printStackTrace();
-			}
 		}
 
 		// create frame
-		FlatTestFrame frame = new FlatTestFrame();
+		return new FlatTestFrame( title );
-		frame.setTitle( title + " (Java " + System.getProperty( "java.version" ) + ")" );
-		return frame;
 	}
 
-	private FlatTestFrame() {
+	private FlatTestFrame( String title ) {
+		this.title = title;
+
 		initComponents();
 
 		// initialize look and feels combo box
 		DefaultComboBoxModel<LafInfo> lafModel = new DefaultComboBoxModel<>();
 		lafModel.addElement( new LafInfo( "Flat Light (F1)", FlatLightLaf.class.getName() ) );
 		lafModel.addElement( new LafInfo( "Flat Dark (F2)", FlatDarkLaf.class.getName() ) );
-		lafModel.addElement( new LafInfo( "Flat Test (F3)", FlatTestLaf.class.getName() ) );
+		lafModel.addElement( new LafInfo( "Flat IntelliJ (F3)", FlatIntelliJLaf.class.getName() ) );
-		lafModel.addElement( new LafInfo( "Flat IntelliJ (F4)", FlatIntelliJLaf.class.getName() ) );
+		lafModel.addElement( new LafInfo( "Flat Darcula (F4)", FlatDarculaLaf.class.getName() ) );
-		lafModel.addElement( new LafInfo( "Flat Darcula (F5)", FlatDarculaLaf.class.getName() ) );
+		lafModel.addElement( new LafInfo( "Flat Test (F8)", FlatTestLaf.class.getName() ) );
 
 		UIManager.LookAndFeelInfo[] lookAndFeels = UIManager.getInstalledLookAndFeels();
 		for( UIManager.LookAndFeelInfo lookAndFeel : lookAndFeels ) {
@@ -85,7 +99,8 @@ public class FlatTestFrame
 			  continue;
 
 			if( (SystemInfo.IS_WINDOWS && className.equals( "com.sun.java.swing.plaf.windows.WindowsLookAndFeel" )) ||
-				(SystemInfo.IS_MAC && className.equals( "com.apple.laf.AquaLookAndFeel") ) )
+				(SystemInfo.IS_MAC && className.equals( "com.apple.laf.AquaLookAndFeel") ) ||
+				(SystemInfo.IS_LINUX && className.equals( "com.sun.java.swing.plaf.gtk.GTKLookAndFeel") ) )
 				name += " (F9)";
 			else if( className.equals( MetalLookAndFeel.class.getName() ) )
 				name += " (F10)";
@@ -106,17 +121,25 @@ public class FlatTestFrame
 
 		lookAndFeelComboBox.setModel( lafModel );
 
-		// register F1, F2 and F3 keys to switch to Light, Dark or Test LaF
+		updateScaleFactorComboBox();
+		String scaleFactor = System.getProperty( "flatlaf.uiScale", System.getProperty( "sun.java2d.uiScale" ) );
+		if( scaleFactor != null )
+			scaleFactorComboBox.setSelectedItem( scaleFactor );
+
+		// register F1, F2, ... keys to switch to Light, Dark or other LaFs
 		registerSwitchToLookAndFeel( KeyEvent.VK_F1, FlatLightLaf.class.getName() );
 		registerSwitchToLookAndFeel( KeyEvent.VK_F2, FlatDarkLaf.class.getName() );
-		registerSwitchToLookAndFeel( KeyEvent.VK_F3, FlatTestLaf.class.getName() );
+		registerSwitchToLookAndFeel( KeyEvent.VK_F3, FlatIntelliJLaf.class.getName() );
-		registerSwitchToLookAndFeel( KeyEvent.VK_F4, FlatIntelliJLaf.class.getName() );
+		registerSwitchToLookAndFeel( KeyEvent.VK_F4, FlatDarculaLaf.class.getName() );
-		registerSwitchToLookAndFeel( KeyEvent.VK_F5, FlatDarculaLaf.class.getName() );
+
+		registerSwitchToLookAndFeel( KeyEvent.VK_F8, FlatTestLaf.class.getName() );
 
 		if( SystemInfo.IS_WINDOWS )
 			registerSwitchToLookAndFeel( KeyEvent.VK_F9, "com.sun.java.swing.plaf.windows.WindowsLookAndFeel" );
 		else if( SystemInfo.IS_MAC )
 			registerSwitchToLookAndFeel( KeyEvent.VK_F9, "com.apple.laf.AquaLookAndFeel" );
+		else if( SystemInfo.IS_LINUX )
+			registerSwitchToLookAndFeel( KeyEvent.VK_F9, "com.sun.java.swing.plaf.gtk.GTKLookAndFeel" );
 		registerSwitchToLookAndFeel( KeyEvent.VK_F10, MetalLookAndFeel.class.getName() );
 		registerSwitchToLookAndFeel( KeyEvent.VK_F11, NimbusLookAndFeel.class.getName() );
 
@@ -130,6 +153,47 @@ public class FlatTestFrame
 
 		// close frame
 		closeButton.addActionListener(e -> dispose());
+
+		// update title
+		addWindowListener( new WindowAdapter() {
+			@Override
+			public void windowOpened( WindowEvent e ) {
+				updateTitle();
+			}
+		} );
+
+		// update title when moved to another screen
+		addComponentListener( new ComponentAdapter() {
+			@Override
+			public void componentMoved( ComponentEvent e ) {
+				updateTitle();
+			}
+		} );
+
+		UIManager.addPropertyChangeListener( e -> {
+			if( "lookAndFeel".equals( e.getPropertyName() ) ) {
+				EventQueue.invokeLater( () -> {
+					// update title because user scale factor may change
+					updateTitle();
+
+					// enable/disable scale factor combobox
+					updateScaleFactorComboBox();
+				} );
+			}
+		} );
+	}
+
+	private void updateTitle() {
+		double systemScaleFactor = UIScale.getSystemScaleFactor( getGraphicsConfiguration() );
+		float userScaleFactor = UIScale.getUserScaleFactor();
+		String newTitle = title + " (Java " + System.getProperty( "java.version" )
+			+ (systemScaleFactor != 1 ? (";  system scale factor " + systemScaleFactor) : "")
+			+ (userScaleFactor != 1 ? (";  user scale factor " + userScaleFactor) : "")
+			+ (systemScaleFactor == 1 && userScaleFactor == 1 ? "; no scaling" : "")
+			+ ")";
+
+		if( !newTitle.equals( getTitle() ) )
+			setTitle( newTitle );
 	}
 
 	private void registerSwitchToLookAndFeel( int keyCode, String lafClassName ) {
@@ -169,22 +233,48 @@ public class FlatTestFrame
 		if( newLaf.className.equals( UIManager.getLookAndFeel().getClass().getName() ) )
 			return;
 
+		// hide popup to avoid occasional StackOverflowError when updating UI
+		lookAndFeelComboBox.setPopupVisible( false );
+
 		Preferences.userRoot().node( PREFS_ROOT_PATH ).put( KEY_LAF, newLaf.className );
 
+		applyLookAndFeel( newLaf.className, false );
+	}
+
+	private void applyLookAndFeel( String lafClassName, boolean pack ) {
 		EventQueue.invokeLater( () -> {
 			try {
 				// change look and feel
-				UIManager.setLookAndFeel( newLaf.className );
+				UIManager.setLookAndFeel( lafClassName );
 
 				// update all components
-				SwingUtilities.updateComponentTreeUI( this );
+				FlatLaf.updateUI();
 
 				// increase size of frame if necessary
+				if( pack )
+					pack();
+				else {
 					int width = getWidth();
 					int height = getHeight();
 					Dimension prefSize = getPreferredSize();
 					if( prefSize.width > width || prefSize.height > height )
 						setSize( Math.max( prefSize.width, width ), Math.max( prefSize.height, height ) );
+				}
+
+				// limit frame size to screen size
+				Rectangle screenBounds = getGraphicsConfiguration().getBounds();
+				screenBounds = FlatUIUtils.subtractInsets( screenBounds, getToolkit().getScreenInsets( getGraphicsConfiguration() ) );
+				Dimension frameSize = getSize();
+				if( frameSize.width > screenBounds.width || frameSize.height > screenBounds.height )
+					setSize( Math.min( frameSize.width, screenBounds.width ), Math.min( frameSize.height, screenBounds.height ) );
+
+				// move frame to left/top if necessary
+				if( getX() + getWidth() > screenBounds.x + screenBounds.width ||
+					getY() + getHeight() > screenBounds.y + screenBounds.height )
+				{
+					setLocation( Math.min( getX(), screenBounds.x + screenBounds.width - getWidth() ),
+								 Math.min( getY(), screenBounds.y + screenBounds.height - getHeight() ) );
+				}
 
 				if( inspector != null )
 					inspector.update();
@@ -289,6 +379,31 @@ public class FlatTestFrame
 		inspector.setEnabled( inspectCheckBox.isSelected() );
 	}
 
+	private void scaleFactorChanged() {
+		String scaleFactor = (String) scaleFactorComboBox.getSelectedItem();
+		if( "default".equals( scaleFactor ) )
+			scaleFactor = null;
+
+		// hide popup to avoid occasional StackOverflowError when updating UI
+		scaleFactorComboBox.setPopupVisible( false );
+
+		Preferences prefs = Preferences.userRoot().node( PREFS_ROOT_PATH );
+
+		if( scaleFactor != null ) {
+			System.setProperty( "flatlaf.uiScale", scaleFactor );
+			prefs.put( KEY_SCALE_FACTOR, scaleFactor );
+		} else {
+			System.clearProperty( "flatlaf.uiScale" );
+			prefs.remove( KEY_SCALE_FACTOR );
+		}
+
+		applyLookAndFeel( UIManager.getLookAndFeel().getClass().getName(), true );
+	}
+
+	private void updateScaleFactorComboBox() {
+		scaleFactorComboBox.setEnabled( !UIScale.isSystemScalingEnabled() && UIManager.getLookAndFeel() instanceof FlatLaf );
+	}
+
 	private void initComponents() {
 		// JFormDesigner - Component initialization - DO NOT MODIFY  //GEN-BEGIN:initComponents
 		dialogPane = new JPanel();
@@ -299,6 +414,7 @@ public class FlatTestFrame
 		rightToLeftCheckBox = new JCheckBox();
 		enabledCheckBox = new JCheckBox();
 		inspectCheckBox = new JCheckBox();
+		scaleFactorComboBox = new JComboBox<>();
 		closeButton = new JButton();
 
 		//======== this ========
@@ -332,6 +448,7 @@ public class FlatTestFrame
 					"[fill]" +
 					"[fill]" +
 					"[fill]" +
+					"[fill]" +
 					"[grow,fill]" +
 					"[button,fill]",
 					// rows
@@ -366,9 +483,27 @@ public class FlatTestFrame
 				inspectCheckBox.addActionListener(e -> inspectChanged());
 				buttonBar.add(inspectCheckBox, "cell 4 0");
 
+				//---- scaleFactorComboBox ----
+				scaleFactorComboBox.setModel(new DefaultComboBoxModel<>(new String[] {
+					"default",
+					"1",
+					"1.25",
+					"1.5",
+					"1.75",
+					"2.0",
+					"2.25",
+					"2.5",
+					"3",
+					"3.5",
+					"4"
+				}));
+				scaleFactorComboBox.setMaximumRowCount(20);
+				scaleFactorComboBox.addActionListener(e -> scaleFactorChanged());
+				buttonBar.add(scaleFactorComboBox, "cell 5 0");
+
 				//---- closeButton ----
 				closeButton.setText("Close");
-				buttonBar.add(closeButton, "cell 6 0");
+				buttonBar.add(closeButton, "cell 7 0");
 			}
 			dialogPane.add(buttonBar, BorderLayout.SOUTH);
 		}
@@ -385,6 +520,7 @@ public class FlatTestFrame
 	private JCheckBox rightToLeftCheckBox;
 	private JCheckBox enabledCheckBox;
 	private JCheckBox inspectCheckBox;
+	private JComboBox<String> scaleFactorComboBox;
 	private JButton closeButton;
 	// JFormDesigner - End of variables declaration  //GEN-END:variables
 

flatlaf-core/src/test/java/com/formdev/flatlaf/FlatTestFrame.jfd

@@ -21,7 +21,7 @@ new FormModel {
 				} )
 				add( new FormContainer( "javax.swing.JPanel", new FormLayoutManager( class net.miginfocom.swing.MigLayout ) {
 					"$layoutConstraints": "insets dialog"
-					"$columnConstraints": "[fill][fill][fill][fill][fill][grow,fill][button,fill]"
+					"$columnConstraints": "[fill][fill][fill][fill][fill][fill][grow,fill][button,fill]"
 					"$rowSpecs": "[fill]"
 				} ) {
 					name: "buttonBar"
@@ -67,11 +67,35 @@ new FormModel {
 					}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
 						"value": "cell 4 0"
 					} )
+					add( new FormComponent( "javax.swing.JComboBox" ) {
+						name: "scaleFactorComboBox"
+						"model": new javax.swing.DefaultComboBoxModel {
+							selectedItem: "default"
+							addElement( "default" )
+							addElement( "1" )
+							addElement( "1.25" )
+							addElement( "1.5" )
+							addElement( "1.75" )
+							addElement( "2.0" )
+							addElement( "2.25" )
+							addElement( "2.5" )
+							addElement( "3" )
+							addElement( "3.5" )
+							addElement( "4" )
+						}
+						"maximumRowCount": 20
+						auxiliary() {
+							"JavaCodeGenerator.typeParameters": "String"
+						}
+						addEvent( new FormEvent( "java.awt.event.ActionListener", "actionPerformed", "scaleFactorChanged", false ) )
+					}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
+						"value": "cell 5 0"
+					} )
 					add( new FormComponent( "javax.swing.JButton" ) {
 						name: "closeButton"
 						"text": "Close"
 					}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
-						"value": "cell 6 0"
+						"value": "cell 7 0"
 					} )
 				}, new FormLayoutConstraints( class java.lang.String ) {
 					"value": "South"
@@ -81,7 +105,7 @@ new FormModel {
 			} )
 		}, new FormLayoutConstraints( null ) {
 			"location": new java.awt.Point( 0, 0 )
-			"size": new java.awt.Dimension( 510, 300 )
+			"size": new java.awt.Dimension( 640, 300 )
 		} )
 	}
 }

flatlaf-demo/build.gradle.kts

@@ -28,7 +28,7 @@ dependencies {
 	implementation( project( ":flatlaf-core" ) )
 	implementation( "com.miglayout:miglayout-swing:5.2" )
 	implementation( "com.jgoodies:jgoodies-forms:1.9.0" )
-	implementation( "guru.nidi.com.kitfox:svgSalamander:1.1.2" )
+	implementation( "com.formdev:svgSalamander:1.1.2.1" )
 }
 
 java {
@@ -42,6 +42,8 @@ tasks {
 			attributes( "Main-Class" to "com.formdev.flatlaf.demo.FlatLafDemo" )
 		}
 
+		exclude( "META-INF/versions/**" )
+
 		// include all dependencies in jar
 		from( {
 			configurations.runtimeClasspath.get().filter { it.name.endsWith( "jar" ) }.map { zipTree( it ) }

flatlaf-demo/src/main/java/com/formdev/flatlaf/demo/BasicComponentsPanel.java

@@ -39,6 +39,7 @@ class BasicComponentsPanel
 		JButton button2 = new JButton();
 		JButton button3 = new JButton();
 		JButton button4 = new JButton();
+		JButton button13 = new JButton();
 		JLabel checkBoxLabel = new JLabel();
 		JCheckBox checkBox1 = new JCheckBox();
 		JCheckBox checkBox2 = new JCheckBox();
@@ -169,6 +170,10 @@ class BasicComponentsPanel
 		button4.setEnabled(false);
 		add(button4, "cell 4 1");
 
+		//---- button13 ----
+		button13.setIcon(UIManager.getIcon("Tree.closedIcon"));
+		add(button13, "cell 5 1");
+
 		//---- checkBoxLabel ----
 		checkBoxLabel.setText("JCheckBox");
 		add(checkBoxLabel, "cell 0 2");

flatlaf-demo/src/main/java/com/formdev/flatlaf/demo/BasicComponentsPanel.jfd

@@ -69,6 +69,12 @@ new FormModel {
 			}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
 				"value": "cell 4 1"
 			} )
+			add( new FormComponent( "javax.swing.JButton" ) {
+				name: "button13"
+				"icon": new com.jformdesigner.model.SwingIcon( 2, "Tree.closedIcon" )
+			}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
+				"value": "cell 5 1"
+			} )
 			add( new FormComponent( "javax.swing.JLabel" ) {
 				name: "checkBoxLabel"
 				"text": "JCheckBox"

flatlaf-demo/src/main/java/com/formdev/flatlaf/demo/ControlBar.java

@@ -17,6 +17,8 @@
 package com.formdev.flatlaf.demo;
 
 import java.awt.*;
+import java.awt.event.ComponentAdapter;
+import java.awt.event.ComponentEvent;
 import java.awt.event.KeyEvent;
 import java.awt.event.WindowAdapter;
 import java.awt.event.WindowEvent;
@@ -56,7 +58,8 @@ class ControlBar
 			  continue;
 
 			if( (SystemInfo.IS_WINDOWS && className.equals( "com.sun.java.swing.plaf.windows.WindowsLookAndFeel" )) ||
-				(SystemInfo.IS_MAC && className.equals( "com.apple.laf.AquaLookAndFeel") ) )
+				(SystemInfo.IS_MAC && className.equals( "com.apple.laf.AquaLookAndFeel") ) ||
+				(SystemInfo.IS_LINUX && className.equals( "com.sun.java.swing.plaf.gtk.GTKLookAndFeel") ) )
 				name += " (F9)";
 			else if( className.equals( MetalLookAndFeel.class.getName() ) )
 				name += " (F10)";
@@ -76,6 +79,15 @@ class ControlBar
 		lafModel.setSelectedItem( lafModel.getElementAt( sel ) );
 
 		lookAndFeelComboBox.setModel( lafModel );
+
+		UIManager.addPropertyChangeListener( e -> {
+			if( "lookAndFeel".equals( e.getPropertyName() ) ) {
+				EventQueue.invokeLater( () -> {
+					// update info label because user scale factor may change
+					updateInfoLabel();
+				} );
+			}
+		} );
 	}
 
 	void initialize( JFrame frame, JTabbedPane tabbedPane ) {
@@ -92,6 +104,8 @@ class ControlBar
 			registerSwitchToLookAndFeel( KeyEvent.VK_F9, "com.sun.java.swing.plaf.windows.WindowsLookAndFeel" );
 		else if( SystemInfo.IS_MAC )
 			registerSwitchToLookAndFeel( KeyEvent.VK_F9, "com.apple.laf.AquaLookAndFeel" );
+		else if( SystemInfo.IS_LINUX )
+			registerSwitchToLookAndFeel( KeyEvent.VK_F9, "com.sun.java.swing.plaf.gtk.GTKLookAndFeel" );
 		registerSwitchToLookAndFeel( KeyEvent.VK_F10, MetalLookAndFeel.class.getName() );
 		registerSwitchToLookAndFeel( KeyEvent.VK_F11, NimbusLookAndFeel.class.getName() );
 
@@ -106,15 +120,19 @@ class ControlBar
 		// make the "close" button the default button
 		frame.getRootPane().setDefaultButton( closeButton );
 
-		// move focus to "close" button
+		// update info label and move focus to "close" button
 		frame.addWindowListener( new WindowAdapter() {
 			@Override
 			public void windowOpened( WindowEvent e ) {
 				updateInfoLabel();
 				closeButton.requestFocusInWindow();
 			}
+		} );
+
+		// update info label when moved to another screen
+		frame.addComponentListener( new ComponentAdapter() {
 			@Override
-			public void windowActivated( WindowEvent e ) {
+			public void componentMoved( ComponentEvent e ) {
 				updateInfoLabel();
 			}
 		} );
@@ -123,11 +141,14 @@ class ControlBar
 	private void updateInfoLabel() {
 		double systemScaleFactor = UIScale.getSystemScaleFactor( getGraphicsConfiguration() );
 		float userScaleFactor = UIScale.getUserScaleFactor();
-		infoLabel.setText( "(Java " + System.getProperty( "java.version" )
+		String newInfo = "(Java " + System.getProperty( "java.version" )
 			+ (systemScaleFactor != 1 ? (";  system scale factor " + systemScaleFactor) : "")
 			+ (userScaleFactor != 1 ? (";  user scale factor " + userScaleFactor) : "")
 			+ (systemScaleFactor == 1 && userScaleFactor == 1 ? "; no scaling" : "")
-			+ ")" );
+			+ ")";
+
+		if( !newInfo.equals( infoLabel.getText() ) )
+			infoLabel.setText( newInfo );
 	}
 
 	private void registerSwitchToLookAndFeel( int keyCode, String lafClassName ) {
@@ -161,11 +182,8 @@ class ControlBar
 				// change look and feel
 				UIManager.setLookAndFeel( newLaf.className );
 
-				// update info label because user scale factor may change
-				updateInfoLabel();
-
 				// update all components
-				SwingUtilities.updateComponentTreeUI( frame );
+				FlatLaf.updateUI();
 
 				// increase size of frame if necessary
 				int width = frame.getWidth();

flatlaf-demo/src/main/java/com/formdev/flatlaf/demo/FlatLafDemo.java

@@ -46,11 +46,7 @@ public class FlatLafDemo
 			ex.printStackTrace();
 
 			// fallback
-			try {
+			FlatLightLaf.install();
-				UIManager.setLookAndFeel( new FlatLightLaf() );
-			} catch( Exception ex2 ) {
-				ex2.printStackTrace();
-			}
 		}
 
 		// create frame