IntelliJ Themes:

- added themes list to demo (and testing) apps
- added some popular open-source IntelliJ themes to demo
  (downloaded latest .theme.json from source repos;
  see themes.properties for source repo URLs)

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

@@ -71,7 +71,6 @@ class ControlBar
 		}
 
 		lookAndFeelComboBox.setModel( lafModel );
-		lookAndFeelComboBox.selectedLookAndFeel( UIManager.getLookAndFeel() );
 
 		UIManager.addPropertyChangeListener( e -> {
 			if( "lookAndFeel".equals( e.getPropertyName() ) ) {

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

@@ -19,6 +19,7 @@ package com.formdev.flatlaf.demo;
 import java.awt.*;
 import java.awt.event.*;
 import javax.swing.*;
+import com.formdev.flatlaf.demo.intellijthemes.*;
 import net.miginfocom.swing.*;
 
 /**
@@ -87,6 +88,7 @@ class DemoFrame
 		TabsPanel tabsPanel = new TabsPanel();
 		OptionPanePanel optionPanePanel = new OptionPanePanel();
 		controlBar = new ControlBar();
+		IJThemesPanel themesPanel = new IJThemesPanel();
 
 		//======== this ========
 		setTitle("FlatLaf Demo");
@@ -262,6 +264,7 @@ class DemoFrame
 		}
 		contentPane.add(contentPanel, BorderLayout.CENTER);
 		contentPane.add(controlBar, BorderLayout.SOUTH);
+		contentPane.add(themesPanel, BorderLayout.EAST);
 
 		//---- buttonGroup1 ----
 		ButtonGroup buttonGroup1 = new ButtonGroup();

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

@@ -107,6 +107,11 @@ new FormModel {
 			}, new FormLayoutConstraints( class java.lang.String ) {
 				"value": "South"
 			} )
+			add( new FormComponent( "com.formdev.flatlaf.demo.intellijthemes.IJThemesPanel" ) {
+				name: "themesPanel"
+			}, new FormLayoutConstraints( class java.lang.String ) {
+				"value": "East"
+			} )
 			menuBar: new FormContainer( "javax.swing.JMenuBar", new FormLayoutManager( class javax.swing.JMenuBar ) ) {
 				name: "menuBar1"
 				add( new FormContainer( "javax.swing.JMenu", new FormLayoutManager( class javax.swing.JMenu ) ) {
@@ -220,7 +225,7 @@ new FormModel {
 			}
 		}, new FormLayoutConstraints( null ) {
 			"location": new java.awt.Point( 0, 0 )
-			"size": new java.awt.Dimension( 800, 710 )
+			"size": new java.awt.Dimension( 935, 710 )
 		} )
 		add( new FormNonVisual( "javax.swing.ButtonGroup" ) {
 			name: "buttonGroup1"

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

@@ -17,10 +17,11 @@
 package com.formdev.flatlaf.demo;
 
 import java.awt.Component;
+import java.beans.PropertyChangeEvent;
+import java.beans.PropertyChangeListener;
 import javax.swing.ComboBoxModel;
 import javax.swing.JComboBox;
 import javax.swing.JList;
-import javax.swing.LookAndFeel;
 import javax.swing.MutableComboBoxModel;
 import javax.swing.UIManager;
 import javax.swing.UIManager.LookAndFeelInfo;
@@ -32,6 +33,8 @@ import javax.swing.plaf.basic.BasicComboBoxRenderer;
 public class LookAndFeelsComboBox
 	extends JComboBox<UIManager.LookAndFeelInfo>
 {
+	private final PropertyChangeListener lafListener = this::lafChanged;
+
 	@SuppressWarnings( "unchecked" )
 	public LookAndFeelsComboBox() {
 		setRenderer( new BasicComboBoxRenderer() {
@@ -40,7 +43,9 @@ public class LookAndFeelsComboBox
 			public Component getListCellRendererComponent( JList list, Object value,
 				int index, boolean isSelected, boolean cellHasFocus )
 			{
-				value = ((LookAndFeelInfo)value).getName();
+				value = (value != null)
+					? ((LookAndFeelInfo)value).getName()
+					: UIManager.getLookAndFeel().getName();
 				return super.getListCellRendererComponent( list, value, index, isSelected, cellHasFocus );
 			}
 		} );
@@ -56,19 +61,11 @@ public class LookAndFeelsComboBox
 	}
 
 	public void setSelectedLookAndFeel( String className ) {
-		int index = getIndexOfLookAndFeel( className );
-		if( index >= 0 )
-			setSelectedIndex( index );
+		setSelectedIndex( getIndexOfLookAndFeel( className ) );
 	}
 
-	public void selectedLookAndFeel( LookAndFeel lookAndFeel ) {
-		String className = lookAndFeel.getClass().getName();
-		int index = getIndexOfLookAndFeel( className );
-		if( index < 0 ) {
-			addLookAndFeel( lookAndFeel.getName(), className );
-			index = getItemCount() - 1;
-		}
-		setSelectedIndex( index );
+	public void selectedCurrentLookAndFeel() {
+		setSelectedLookAndFeel( UIManager.getLookAndFeel().getClass().getName() );
 	}
 
 	public void removeLookAndFeel( String className ) {
@@ -90,4 +87,24 @@ public class LookAndFeelsComboBox
 	private MutableComboBoxModel<LookAndFeelInfo> getMutableModel() {
 		return (MutableComboBoxModel<LookAndFeelInfo>) getModel();
 	}
+
+	@Override
+	public void addNotify() {
+		super.addNotify();
+
+		selectedCurrentLookAndFeel();
+		UIManager.addPropertyChangeListener( lafListener );
+	}
+
+	@Override
+	public void removeNotify() {
+		super.removeNotify();
+
+		UIManager.removePropertyChangeListener( lafListener );
+	}
+
+	void lafChanged( PropertyChangeEvent e ) {
+		if( "lookAndFeel".equals( e.getPropertyName() ) )
+			selectedCurrentLookAndFeel();
+	}
 }

flatlaf-demo/src/main/java/com/formdev/flatlaf/demo/intellijthemes/IJThemeInfo.java

@@ -0,0 +1,32 @@
+/*
+ * 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.demo.intellijthemes;
+
+/**
+ * @author Karl Tauber
+ */
+class IJThemeInfo
+{
+	String name;
+	String resourceName;
+	String sourceCodeUrl;
+
+	@Override
+	public String toString() {
+		return name;
+	}
+}

flatlaf-demo/src/main/java/com/formdev/flatlaf/demo/intellijthemes/IJThemesManager.java

@@ -0,0 +1,56 @@
+/*
+ * 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.demo.intellijthemes;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Map;
+import java.util.Properties;
+import com.formdev.flatlaf.util.StringUtils;
+
+/**
+ * @author Karl Tauber
+ */
+class IJThemesManager
+{
+	final List<IJThemeInfo> bundledThemes = new ArrayList<>();
+
+	void loadBundledThemes() {
+		// load themes.properties
+		Properties properties = new Properties();
+		try( InputStream in = getClass().getResourceAsStream( "themes.properties" ) ) {
+			if( in != null )
+				properties.load( in );
+		} catch( IOException ex ) {
+			ex.printStackTrace();
+		}
+
+		// add info about bundled themes
+		for( Map.Entry<Object, Object> e : properties.entrySet() ) {
+			String resourceName = (String) e.getKey();
+			List<String> strs = StringUtils.split( (String) e.getValue(), ',' );
+
+			IJThemeInfo themeInfo = new IJThemeInfo();
+			themeInfo.name = strs.get( 0 );
+			themeInfo.resourceName = resourceName;
+			themeInfo.sourceCodeUrl = strs.get( 1 );
+			bundledThemes.add( themeInfo );
+		}
+	}
+}

flatlaf-demo/src/main/java/com/formdev/flatlaf/demo/intellijthemes/IJThemesPanel.java

@@ -0,0 +1,145 @@
+/*
+ * 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.demo.intellijthemes;
+
+import java.awt.EventQueue;
+import java.beans.PropertyChangeEvent;
+import java.beans.PropertyChangeListener;
+import java.util.ArrayList;
+import java.util.List;
+import javax.swing.*;
+import javax.swing.event.*;
+import com.formdev.flatlaf.FlatLaf;
+import com.formdev.flatlaf.IntelliJTheme;
+import net.miginfocom.swing.*;
+
+/**
+ * @author Karl Tauber
+ */
+public class IJThemesPanel
+	extends JPanel
+{
+	private final IJThemesManager themesManager = new IJThemesManager();
+	private final PropertyChangeListener lafListener = this::lafChanged;
+
+	public IJThemesPanel() {
+		initComponents();
+
+		// load theme infos
+		themesManager.loadBundledThemes();
+
+		// sort themes by name
+		List<IJThemeInfo> themes = new ArrayList<>();
+		themes.addAll( themesManager.bundledThemes );
+		themes.sort( (t1, t2) -> t1.name.compareToIgnoreCase( t2.name ) );
+
+		// fill themes list
+		themesList.setModel( new AbstractListModel<IJThemeInfo>() {
+			@Override
+			public int getSize() {
+				return themes.size();
+			}
+			@Override
+			public IJThemeInfo getElementAt( int index ) {
+				return themes.get( index );
+			}
+		} );
+	}
+
+	private void themesListValueChanged( ListSelectionEvent e ) {
+		if( e.getValueIsAdjusting() )
+			return;
+
+		EventQueue.invokeLater( () -> {
+			setTheme( themesList.getSelectedValue() );
+		} );
+	}
+
+	private void setTheme( IJThemeInfo themeInfo ) {
+		if( themeInfo == null )
+			return;
+
+		// change look and feel
+		IntelliJTheme.install( getClass().getResourceAsStream( themeInfo.resourceName ) );
+
+		// update all components
+		FlatLaf.updateUI();
+	}
+
+	@Override
+	public void addNotify() {
+		super.addNotify();
+
+		selectedCurrentLookAndFeel();
+		UIManager.addPropertyChangeListener( lafListener );
+	}
+
+	@Override
+	public void removeNotify() {
+		super.removeNotify();
+
+		UIManager.removePropertyChangeListener( lafListener );
+	}
+
+	void lafChanged( PropertyChangeEvent e ) {
+		if( "lookAndFeel".equals( e.getPropertyName() ) )
+			selectedCurrentLookAndFeel();
+	}
+
+	private void selectedCurrentLookAndFeel() {
+		LookAndFeel lookAndFeel = UIManager.getLookAndFeel();
+
+		if( !(lookAndFeel instanceof IntelliJTheme.ThemeLaf) )
+			themesList.clearSelection();
+	}
+
+	private void initComponents() {
+		// JFormDesigner - Component initialization - DO NOT MODIFY  //GEN-BEGIN:initComponents
+		JLabel themesLabel = new JLabel();
+		themesScrollPane = new JScrollPane();
+		themesList = new JList<>();
+
+		//======== this ========
+		setLayout(new MigLayout(
+			"insets dialog,hidemode 3",
+			// columns
+			"[grow,fill]",
+			// rows
+			"[]" +
+			"[grow,fill]"));
+
+		//---- themesLabel ----
+		themesLabel.setText("Themes:");
+		add(themesLabel, "cell 0 0");
+
+		//======== themesScrollPane ========
+		{
+
+			//---- themesList ----
+			themesList.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
+			themesList.addListSelectionListener(e -> themesListValueChanged(e));
+			themesScrollPane.setViewportView(themesList);
+		}
+		add(themesScrollPane, "cell 0 1");
+		// JFormDesigner - End of component initialization  //GEN-END:initComponents
+	}
+
+	// JFormDesigner - Variables declaration - DO NOT MODIFY  //GEN-BEGIN:variables
+	private JScrollPane themesScrollPane;
+	private JList<IJThemeInfo> themesList;
+	// JFormDesigner - End of variables declaration  //GEN-END:variables
+}

flatlaf-demo/src/main/java/com/formdev/flatlaf/demo/intellijthemes/IJThemesPanel.jfd

@@ -0,0 +1,39 @@
+JFDML JFormDesigner: "7.0.0.0.194" Java: "11.0.2" encoding: "UTF-8"
+
+new FormModel {
+	contentType: "form/swing"
+	root: new FormRoot {
+		add( new FormContainer( "javax.swing.JPanel", new FormLayoutManager( class net.miginfocom.swing.MigLayout ) {
+			"$layoutConstraints": "insets dialog,hidemode 3"
+			"$columnConstraints": "[grow,fill]"
+			"$rowConstraints": "[][grow,fill]"
+		} ) {
+			name: "this"
+			add( new FormComponent( "javax.swing.JLabel" ) {
+				name: "themesLabel"
+				"text": "Themes:"
+				auxiliary() {
+					"JavaCodeGenerator.variableLocal": true
+				}
+			}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
+				"value": "cell 0 0"
+			} )
+			add( new FormContainer( "javax.swing.JScrollPane", new FormLayoutManager( class javax.swing.JScrollPane ) ) {
+				name: "themesScrollPane"
+				add( new FormComponent( "javax.swing.JList" ) {
+					name: "themesList"
+					"selectionMode": 0
+					auxiliary() {
+						"JavaCodeGenerator.typeParameters": "IJThemeInfo"
+					}
+					addEvent( new FormEvent( "javax.swing.event.ListSelectionListener", "valueChanged", "themesListValueChanged", true ) )
+				} )
+			}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
+				"value": "cell 0 1"
+			} )
+		}, new FormLayoutConstraints( null ) {
+			"location": new java.awt.Point( 0, 0 )
+			"size": new java.awt.Dimension( 400, 300 )
+		} )
+	}
+}