Menus: support "underline" menu selection type (suggested in issue #49)

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

@@ -30,7 +30,8 @@
  *
  * @uiDefault MenuItemCheckBox.icon.checkmarkColor				Color
  * @uiDefault MenuItemCheckBox.icon.disabledCheckmarkColor		Color
- * @uiDefault Menu.selectionForeground							Color
+ * @uiDefault MenuItem.selectionForeground						Color
+ * @uiDefault MenuItem.selectionType							String
  *
  * @author Karl Tauber
  */
@@ -39,7 +40,7 @@ public class FlatCheckBoxMenuItemIcon
 {
 	protected final Color checkmarkColor = UIManager.getColor( "MenuItemCheckBox.icon.checkmarkColor" );
 	protected final Color disabledCheckmarkColor = UIManager.getColor( "MenuItemCheckBox.icon.disabledCheckmarkColor" );
-	protected final Color selectionForeground = UIManager.getColor( "Menu.selectionForeground" );
+	protected final Color selectionForeground = UIManager.getColor( "MenuItem.selectionForeground" );
 
 	public FlatCheckBoxMenuItemIcon() {
 		super( 15, 15, null );
@@ -67,9 +68,14 @@ protected void paintCheckmark( Graphics2D g2 ) {
 	}
 
 	private Color getCheckmarkColor( Component c ) {
-		if( c instanceof JMenuItem && ((JMenuItem)c).isArmed() )
+		if( c instanceof JMenuItem && ((JMenuItem)c).isArmed() && !isUnderlineSelection() )
 			return selectionForeground;
 
 		return c.isEnabled() ? checkmarkColor : disabledCheckmarkColor;
 	}
+
+	private boolean isUnderlineSelection() {
+		// not storing value of "MenuItem.selectionType" in class to allow changing at runtime
+		return "underline".equals( UIManager.getString( "MenuItem.selectionType" ) );
+	}
 }

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

@@ -32,6 +32,7 @@
  * @uiDefault Menu.icon.arrowColor				Color
  * @uiDefault Menu.icon.disabledArrowColor		Color
  * @uiDefault Menu.selectionForeground			Color
+ * @uiDefault MenuItem.selectionType			String
  *
  * @author Karl Tauber
  */
@@ -65,9 +66,14 @@ protected void paintIcon( Component c, Graphics2D g ) {
 	}
 
 	private Color getArrowColor( Component c ) {
-		if( c instanceof JMenu && ((JMenu)c).isSelected() )
+		if( c instanceof JMenu && ((JMenu)c).isSelected() && !isUnderlineSelection() )
 			return selectionForeground;
 
 		return c.isEnabled() ? arrowColor : disabledArrowColor;
 	}
+
+	private boolean isUnderlineSelection() {
+		// not storing value of "MenuItem.selectionType" in class to allow changing at runtime
+		return "underline".equals( UIManager.getString( "MenuItem.selectionType" ) );
+	}
 }

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

@@ -55,6 +55,11 @@ public class FlatMenuItemRenderer
 	protected final int textAcceleratorGap;
 	protected final int textArrowGap;
 
+	protected final String selectionType = UIManager.getString( "MenuItem.selectionType" );
+	protected final Color underlineSelectionBackground = UIManager.getColor( "MenuItem.underlineSelectionBackground" );
+	protected final Color underlineSelectionColor = UIManager.getColor( "MenuItem.underlineSelectionColor" );
+	protected final int underlineSelectionHeight = UIManager.getInt( "MenuItem.underlineSelectionHeight" );
+
 	protected FlatMenuItemRenderer( JMenuItem menuItem, Icon checkIcon, Icon arrowIcon,
 		Font acceleratorFont, String acceleratorDelimiter )
 	{
@@ -226,8 +231,30 @@ protected void paintMenuItem( Graphics g, Color selectionBackground, Color selec
 	protected void paintBackground( Graphics g, Color selectionBackground ) {
 		boolean armedOrSelected = isArmedOrSelected( menuItem );
 		if( menuItem.isOpaque() || armedOrSelected ) {
-			g.setColor( armedOrSelected ? selectionBackground : menuItem.getBackground() );
-			g.fillRect( 0, 0, menuItem.getWidth(), menuItem.getHeight() );
+			int width = menuItem.getWidth();
+			int height = menuItem.getHeight();
+
+			// paint background
+			g.setColor( armedOrSelected
+				? (isUnderlineSelection() ? underlineSelectionBackground : selectionBackground)
+				: menuItem.getBackground() );
+			g.fillRect( 0, 0, width, height );
+
+			// paint underline
+			if( armedOrSelected && isUnderlineSelection() ) {
+				int underlineHeight = scale( underlineSelectionHeight );
+				g.setColor( underlineSelectionColor );
+				if( isTopLevelMenu( menuItem ) ) {
+					// paint underline at bottom
+					g.fillRect( 0, height - underlineHeight, width, underlineHeight );
+				} else if( menuItem.getComponentOrientation().isLeftToRight() ) {
+					// paint underline at left side
+					g.fillRect( 0, 0, underlineHeight, height );
+				} else {
+					// paint underline at right side
+					g.fillRect( width - underlineHeight, 0, underlineHeight, height );
+				}
+			}
 		}
 	}
 
@@ -252,16 +279,17 @@ protected void paintText( Graphics g, Rectangle textRect, String text, Color sel
 		}
 
 		int mnemonicIndex = FlatLaf.isShowMnemonics() ? menuItem.getDisplayedMnemonicIndex() : -1;
+		Color foreground = menuItem.getForeground();
 
 		paintText( g, menuItem, textRect, text, mnemonicIndex, menuItem.getFont(),
-			menuItem.getForeground(), selectionForeground, disabledForeground );
+			foreground, isUnderlineSelection() ? foreground : selectionForeground, disabledForeground );
 	}
 
 	protected void paintAccelerator( Graphics g, Rectangle accelRect, String accelText,
 		Color foreground, Color selectionForeground, Color disabledForeground )
 	{
 		paintText( g, menuItem, accelRect, accelText, -1, acceleratorFont,
-			foreground, selectionForeground, disabledForeground );
+			foreground, isUnderlineSelection() ? foreground : selectionForeground, disabledForeground );
 	}
 
 	protected void paintArrowIcon( Graphics g, Rectangle arrowRect, Icon arrowIcon ) {
@@ -311,6 +339,10 @@ protected static boolean isTopLevelMenu( JMenuItem menuItem ) {
 		return menuItem instanceof JMenu && ((JMenu)menuItem).isTopLevelMenu();
 	}
 
+	private boolean isUnderlineSelection() {
+		return "underline".equals( selectionType );
+	}
+
 	private Icon getIconForPainting() {
 		Icon icon = menuItem.getIcon();
 

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

@@ -29,6 +29,7 @@
 @disabledText=#777777
 @textComponentBackground=#45494A
 @menuBackground=darken(@background,5%)
+@menuHoverBackground=lighten(@menuBackground,10%)
 @menuCheckBackground=lighten(@menuBackground,15%)
 @cellFocusColor=#000000
 @icon=#adadad
@@ -171,7 +172,7 @@ Menu.icon.disabledArrowColor=#606060
 #---- MenuBar ----
 
 MenuBar.borderColor=#515151
-MenuBar.hoverBackground=lighten($MenuBar.background,10%)
+MenuBar.hoverBackground=@menuHoverBackground
 
 
 #---- MenuItemCheckBox ----

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

@@ -319,6 +319,11 @@ MenuItem.textArrowGap=8
 MenuItem.acceleratorDelimiter=-
 [mac]MenuItem.acceleratorDelimiter=
 
+# for MenuItem.selectionType=underline
+MenuItem.underlineSelectionBackground=@menuHoverBackground
+MenuItem.underlineSelectionColor=$TabbedPane.underlineColor
+MenuItem.underlineSelectionHeight=3
+
 
 #---- OptionPane ----
 

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

@@ -29,6 +29,7 @@
 @disabledText=#8C8C8C
 @textComponentBackground=#ffffff
 @menuBackground=#fff
+@menuHoverBackground=darken(@menuBackground,10%)
 @menuCheckBackground=darken(@menuBackground,15%)
 @cellFocusColor=#000000
 @icon=#afafaf
@@ -178,7 +179,7 @@ Menu.icon.disabledArrowColor=#ABABAB
 #---- MenuBar ----
 
 MenuBar.borderColor=#cdcdcd
-MenuBar.hoverBackground=darken($MenuBar.background,10%)
+MenuBar.hoverBackground=@menuHoverBackground
 
 
 #---- MenuItemCheckBox ----

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

@@ -59,6 +59,11 @@ private void menuItemActionPerformed( ActionEvent e ) {
 		} );
 	}
 
+	private void underlineMenuSelection() {
+		UIManager.put( "MenuItem.selectionType", underlineMenuSelectionMenuItem.isSelected() ? "underline" : null );
+		FlatLaf.updateUI();
+	}
+
 	private void fontFamilyChanged( ActionEvent e ) {
 		String fontFamily = e.getActionCommand();
 
@@ -132,6 +137,8 @@ private void initComponents() {
 		JMenuItem restoreFontMenuItem = new JMenuItem();
 		JMenuItem incrFontMenuItem = new JMenuItem();
 		JMenuItem decrFontMenuItem = new JMenuItem();
+		JMenu optionsMenu = new JMenu();
+		underlineMenuSelectionMenuItem = new JCheckBoxMenuItem();
 		JMenu helpMenu = new JMenu();
 		JMenuItem aboutMenuItem = new JMenuItem();
 		JToolBar toolBar1 = new JToolBar();
@@ -355,6 +362,17 @@ private void initComponents() {
 			}
 			menuBar1.add(fontMenu);
 
+			//======== optionsMenu ========
+			{
+				optionsMenu.setText("Options");
+
+				//---- underlineMenuSelectionMenuItem ----
+				underlineMenuSelectionMenuItem.setText("Use underline menu selection");
+				underlineMenuSelectionMenuItem.addActionListener(e -> underlineMenuSelection());
+				optionsMenu.add(underlineMenuSelectionMenuItem);
+			}
+			menuBar1.add(optionsMenu);
+
 			//======== helpMenu ========
 			{
 				helpMenu.setText("Help");
@@ -481,6 +499,7 @@ private void initComponents() {
 
 	// JFormDesigner - Variables declaration - DO NOT MODIFY  //GEN-BEGIN:variables
 	private JMenu fontMenu;
+	private JCheckBoxMenuItem underlineMenuSelectionMenuItem;
 	private JTabbedPane tabbedPane;
 	private ControlBar controlBar;
 	// JFormDesigner - End of variables declaration  //GEN-END:variables

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

@@ -310,6 +310,18 @@ new FormModel {
 						addEvent( new FormEvent( "java.awt.event.ActionListener", "actionPerformed", "decrFont", false ) )
 					} )
 				} )
+				add( new FormContainer( "javax.swing.JMenu", new FormLayoutManager( class javax.swing.JMenu ) ) {
+					name: "optionsMenu"
+					"text": "Options"
+					add( new FormComponent( "javax.swing.JCheckBoxMenuItem" ) {
+						name: "underlineMenuSelectionMenuItem"
+						"text": "Use underline menu selection"
+						auxiliary() {
+							"JavaCodeGenerator.variableLocal": false
+						}
+						addEvent( new FormEvent( "java.awt.event.ActionListener", "actionPerformed", "underlineMenuSelection", false ) )
+					} )
+				} )
 				add( new FormContainer( "javax.swing.JMenu", new FormLayoutManager( class javax.swing.JMenu ) ) {
 					name: "helpMenu"
 					"text": "Help"

flatlaf-testing/src/main/java/com/formdev/flatlaf/testing/FlatMenusTest.java

@@ -23,6 +23,7 @@
 import java.awt.event.*;
 import java.util.function.Supplier;
 import javax.swing.*;
+import com.formdev.flatlaf.FlatLaf;
 import com.formdev.flatlaf.util.UIScale;
 import net.miginfocom.swing.*;
 
@@ -61,6 +62,11 @@ private void arm( Container container, boolean armed ) {
 		}
 	}
 
+	private void underlineChanged() {
+		UIManager.put( "MenuItem.selectionType", underlineCheckBox.isSelected() ? "underline" : null );
+		FlatLaf.updateUI();
+	}
+
 	private void showPopupMenuButtonActionPerformed(ActionEvent e) {
 		Component invoker = (Component) e.getSource();
 		PopupMenu popupMenu = new PopupMenu();
@@ -193,6 +199,7 @@ private void initComponents() {
 		JLabel popupMenuLabel = new JLabel();
 		JButton showPopupMenuButton = new JButton();
 		armedCheckBox = new JCheckBox();
+		underlineCheckBox = new JCheckBox();
 
 		//======== this ========
 		setLayout(new MigLayout(
@@ -207,6 +214,7 @@ private void initComponents() {
 			"[]" +
 			"[top]" +
 			"[]" +
+			"[]" +
 			"[]"));
 
 		//---- menuBarLabel ----
@@ -691,6 +699,11 @@ private void initComponents() {
 		armedCheckBox.addActionListener(e -> armedChanged());
 		add(armedCheckBox, "cell 0 3");
 
+		//---- underlineCheckBox ----
+		underlineCheckBox.setText("underline menu selection");
+		underlineCheckBox.addActionListener(e -> underlineChanged());
+		add(underlineCheckBox, "cell 0 4 2 1");
+
 		//---- buttonGroup1 ----
 		ButtonGroup buttonGroup1 = new ButtonGroup();
 		buttonGroup1.add(radioButtonMenuItem5);
@@ -708,6 +721,7 @@ private void initComponents() {
 	private JCheckBox largerCheckBox;
 	private JCheckBox accelCheckBox;
 	private JCheckBox armedCheckBox;
+	private JCheckBox underlineCheckBox;
 	// JFormDesigner - End of variables declaration  //GEN-END:variables
 
 	//---- class PopupMenu ----------------------------------------------------

flatlaf-testing/src/main/java/com/formdev/flatlaf/testing/FlatMenusTest.jfd

@@ -9,7 +9,7 @@ new FormModel {
 		add( new FormContainer( "com.formdev.flatlaf.testing.FlatTestPanel", new FormLayoutManager( class net.miginfocom.swing.MigLayout ) {
 			"$layoutConstraints": "ltr,insets dialog,hidemode 3"
 			"$columnConstraints": "[125][][][][]"
-			"$rowConstraints": "[][top][][]"
+			"$rowConstraints": "[][top][][][]"
 		} ) {
 			name: "this"
 			add( new FormComponent( "javax.swing.JLabel" ) {
@@ -528,6 +528,16 @@ new FormModel {
 			}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
 				"value": "cell 0 3"
 			} )
+			add( new FormComponent( "javax.swing.JCheckBox" ) {
+				name: "underlineCheckBox"
+				"text": "underline menu selection"
+				auxiliary() {
+					"JavaCodeGenerator.variableLocal": false
+				}
+				addEvent( new FormEvent( "java.awt.event.ActionListener", "actionPerformed", "underlineChanged", false ) )
+			}, new FormLayoutConstraints( class net.miginfocom.layout.CC ) {
+				"value": "cell 0 4 2 1"
+			} )
 		}, new FormLayoutConstraints( null ) {
 			"location": new java.awt.Point( 0, 0 )
 			"size": new java.awt.Dimension( 790, 380 )

flatlaf-testing/src/main/resources/com/formdev/flatlaf/testing/uidefaults/FlatDarkLaf_1.8.0_202-mac.txt

@@ -527,6 +527,9 @@ MenuItem.selectionBackground   #4b6eaf    javax.swing.plaf.ColorUIResource [UI]
 MenuItem.selectionForeground   #bbbbbb    javax.swing.plaf.ColorUIResource [UI]
 MenuItem.textAcceleratorGap    24
 MenuItem.textArrowGap          8
+MenuItem.underlineSelectionBackground #484c4f    javax.swing.plaf.ColorUIResource [UI]
+MenuItem.underlineSelectionColor #4a88c7    javax.swing.plaf.ColorUIResource [UI]
+MenuItem.underlineSelectionHeight 3
 
 
 #---- MenuItemCheckBox ----

flatlaf-testing/src/main/resources/com/formdev/flatlaf/testing/uidefaults/FlatDarkLaf_1.8.0_202.txt

@@ -526,6 +526,9 @@ MenuItem.selectionBackground   #4b6eaf    javax.swing.plaf.ColorUIResource [UI]
 MenuItem.selectionForeground   #bbbbbb    javax.swing.plaf.ColorUIResource [UI]
 MenuItem.textAcceleratorGap    24
 MenuItem.textArrowGap          8
+MenuItem.underlineSelectionBackground #484c4f    javax.swing.plaf.ColorUIResource [UI]
+MenuItem.underlineSelectionColor #4a88c7    javax.swing.plaf.ColorUIResource [UI]
+MenuItem.underlineSelectionHeight 3
 
 
 #---- MenuItemCheckBox ----

flatlaf-testing/src/main/resources/com/formdev/flatlaf/testing/uidefaults/FlatLightLaf_1.8.0_202-mac.txt

@@ -529,6 +529,9 @@ MenuItem.selectionBackground   #2675bf    javax.swing.plaf.ColorUIResource [UI]
 MenuItem.selectionForeground   #ffffff    javax.swing.plaf.ColorUIResource [UI]
 MenuItem.textAcceleratorGap    24
 MenuItem.textArrowGap          8
+MenuItem.underlineSelectionBackground #e6e6e6    javax.swing.plaf.ColorUIResource [UI]
+MenuItem.underlineSelectionColor #4083c9    javax.swing.plaf.ColorUIResource [UI]
+MenuItem.underlineSelectionHeight 3
 
 
 #---- MenuItemCheckBox ----

flatlaf-testing/src/main/resources/com/formdev/flatlaf/testing/uidefaults/FlatLightLaf_1.8.0_202.txt

@@ -528,6 +528,9 @@ MenuItem.selectionBackground   #2675bf    javax.swing.plaf.ColorUIResource [UI]
 MenuItem.selectionForeground   #ffffff    javax.swing.plaf.ColorUIResource [UI]
 MenuItem.textAcceleratorGap    24
 MenuItem.textArrowGap          8
+MenuItem.underlineSelectionBackground #e6e6e6    javax.swing.plaf.ColorUIResource [UI]
+MenuItem.underlineSelectionColor #4083c9    javax.swing.plaf.ColorUIResource [UI]
+MenuItem.underlineSelectionHeight 3
 
 
 #---- MenuItemCheckBox ----