Window decorations: support right aligned extra components in JFrame title pane with embedded menu bar

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

@@ -16,18 +16,21 @@
 
 package com.formdev.flatlaf.ui;
 
+import java.awt.Graphics;
 import java.awt.event.ActionEvent;
 import javax.swing.AbstractAction;
 import javax.swing.ActionMap;
 import javax.swing.JComponent;
 import javax.swing.JMenu;
 import javax.swing.JMenuBar;
+import javax.swing.LookAndFeel;
 import javax.swing.MenuElement;
 import javax.swing.MenuSelectionManager;
 import javax.swing.SwingUtilities;
 import javax.swing.plaf.ActionMapUIResource;
 import javax.swing.plaf.ComponentUI;
 import javax.swing.plaf.basic.BasicMenuBarUI;
+import com.formdev.flatlaf.FlatClientProperties;
 import com.formdev.flatlaf.FlatLaf;
 import com.formdev.flatlaf.util.SystemInfo;
 
@@ -55,6 +58,13 @@ public class FlatMenuBarUI
 	 *          Do not add any functionality here.
 	 */
 
+	@Override
+	protected void installDefaults() {
+		super.installDefaults();
+
+		LookAndFeel.installProperty( menuBar, "opaque", false );
+	}
+
 	@Override
 	protected void installKeyboardActions() {
 		super.installKeyboardActions();
@@ -67,6 +77,19 @@ public class FlatMenuBarUI
 		map.put( "takeFocus", new TakeFocus() );
 	}
 
+	@Override
+	public void update( Graphics g, JComponent c ) {
+		// do not fill background if menubar is embedded into title pane
+		if( c.isOpaque() ||
+			!FlatClientProperties.clientPropertyBoolean( menuBar, "flatlaf.internal.menuBarEmbedded", false ) )
+		{
+			g.setColor( c.getBackground() );
+			g.fillRect( 0, 0, c.getWidth(), c.getHeight() );
+		}
+
+		paint( g, c );
+	}
+
 	//---- class TakeFocus ----------------------------------------------------
 
 	/**

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

@@ -305,7 +305,8 @@ public class FlatRootPaneUI
 
 			JMenuBar menuBar = rootPane.getJMenuBar();
 			if( menuBar != null && menuBar.isVisible() ) {
-				if( !isFullScreen && titlePane != null && titlePane.isMenuBarEmbedded() ) {
+				boolean embedded = !isFullScreen && titlePane != null && titlePane.isMenuBarEmbedded();
+				if( embedded ) {
 					titlePane.validate();
 					menuBar.setBounds( titlePane.getMenuBarBounds() );
 				} else {
@@ -313,6 +314,9 @@ public class FlatRootPaneUI
 					menuBar.setBounds( 0, nextY, width, prefSize.height );
 					nextY += prefSize.height;
 				}
+
+				// mark menubar as embedded, which is used when painting menubar background
+				menuBar.putClientProperty( "flatlaf.internal.menuBarEmbedded", embedded ? true : null );
 			}
 
 			Container contentPane = rootPane.getContentPane();

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

@@ -47,6 +47,7 @@ import java.util.List;
 import java.util.Objects;
 import javax.accessibility.AccessibleContext;
 import javax.swing.BorderFactory;
+import javax.swing.Box;
 import javax.swing.BoxLayout;
 import javax.swing.Icon;
 import javax.swing.ImageIcon;
@@ -80,7 +81,6 @@ import com.formdev.flatlaf.util.UIScale;
  * @uiDefault TitlePane.iconSize							Dimension
  * @uiDefault TitlePane.iconMargins							Insets
  * @uiDefault TitlePane.titleMargins						Insets
- * @uiDefault TitlePane.menuBarMargins						Insets
  * @uiDefault TitlePane.menuBarEmbedded						boolean
  * @uiDefault TitlePane.buttonMaximizedHeight				int
  * @uiDefault TitlePane.closeIcon							Icon
@@ -100,7 +100,6 @@ public class FlatTitlePane
 	protected final Color embeddedForeground = UIManager.getColor( "TitlePane.embeddedForeground" );
 	protected final Color borderColor = UIManager.getColor( "TitlePane.borderColor" );
 
-	protected final Insets menuBarMargins = UIManager.getInsets( "TitlePane.menuBarMargins" );
 	protected final Dimension iconSize = UIManager.getDimension( "TitlePane.iconSize" );
 	protected final int buttonMaximizedHeight = UIManager.getInt( "TitlePane.buttonMaximizedHeight" );
 
@@ -159,9 +158,7 @@ public class FlatTitlePane
 			@Override
 			public Dimension getPreferredSize() {
 				JMenuBar menuBar = rootPane.getJMenuBar();
-				return (menuBar != null && menuBar.isVisible() && isMenuBarEmbedded())
-					? FlatUIUtils.addInsets( menuBar.getPreferredSize(), UIScale.scale( menuBarMargins ) )
-					: new Dimension();
+				return hasVisibleEmbeddedMenuBar( menuBar ) ? menuBar.getPreferredSize() : new Dimension();
 			}
 		};
 		leftPanel.add( menuBarPlaceholder );
@@ -184,6 +181,18 @@ public class FlatTitlePane
 					if( !getComponentOrientation().isLeftToRight() )
 						leftPanel.setLocation( leftPanel.getX() + (oldWidth - newWidth), leftPanel.getY() );
 				}
+
+				// If menu bar is embedded and contains a horizontal glue component,
+				// then move the title label to the same location as the glue component.
+				// This allows placing any component on the trailing side of the title pane.
+				JMenuBar menuBar = rootPane.getJMenuBar();
+				if( hasVisibleEmbeddedMenuBar( menuBar ) ) {
+					Component horizontalGlue = findHorizontalGlue( menuBar );
+					if( horizontalGlue != null ) {
+						Point glueLocation = SwingUtilities.convertPoint( horizontalGlue, 0, 0, titleLabel );
+						titleLabel.setLocation( titleLabel.getX() + glueLocation.x, titleLabel.getY() );
+					}
+				}
 			}
 		} );
 
@@ -240,7 +249,7 @@ public class FlatTitlePane
 	}
 
 	protected void activeChanged( boolean active ) {
-		boolean hasEmbeddedMenuBar = rootPane.getJMenuBar() != null && rootPane.getJMenuBar().isVisible() && isMenuBarEmbedded();
+		boolean hasEmbeddedMenuBar = hasVisibleEmbeddedMenuBar( rootPane.getJMenuBar() );
 		Color background = FlatUIUtils.nonUIResource( active ? activeBackground : inactiveBackground );
 		Color foreground = FlatUIUtils.nonUIResource( active ? activeForeground : inactiveForeground );
 		Color titleForeground = (hasEmbeddedMenuBar && active) ? FlatUIUtils.nonUIResource( embeddedForeground ) : foreground;
@@ -394,6 +403,16 @@ public class FlatTitlePane
 		window.removeComponentListener( handler );
 	}
 
+	/**
+	 * Returns whether this title pane currently has an visible and embedded menubar.
+	 */
+	protected boolean hasVisibleEmbeddedMenuBar( JMenuBar menuBar ) {
+		return menuBar != null && menuBar.isVisible() && isMenuBarEmbedded();
+	}
+
+	/**
+	 * Returns whether the menubar should be embedded into the title pane.
+	 */
 	protected boolean isMenuBarEmbedded() {
 		// not storing value of "TitlePane.menuBarEmbedded" in class to allow changing at runtime
 		return UIManager.getBoolean( "TitlePane.menuBarEmbedded" ) &&
@@ -412,13 +431,30 @@ public class FlatTitlePane
 		Insets borderInsets = getBorder().getBorderInsets( this );
 		bounds.height += borderInsets.bottom;
 
-		return FlatUIUtils.subtractInsets( bounds, UIScale.scale( getMenuBarMargins() ) );
+		// If menu bar is embedded and contains a horizontal glue component,
+		// then make the menu bar wider so that it completely overlaps the title label.
+		// Since the menu bar is not opaque, the title label is still visible.
+		// The title label is moved to the location of the glue component by the layout manager.
+		// This allows placing any component on the trailing side of the title pane.
+		Component horizontalGlue = findHorizontalGlue( rootPane.getJMenuBar() );
+		if( horizontalGlue != null ) {
+			int titleWidth = Math.max( titleLabel.getWidth(), 0 ); // title width may be negative
+			bounds.width += titleWidth;
+			if( !getComponentOrientation().isLeftToRight() )
+				bounds.x -= titleWidth;
+		}
+
+		return bounds;
 	}
 
-	protected Insets getMenuBarMargins() {
-		return getComponentOrientation().isLeftToRight()
-			? menuBarMargins
-			: new Insets( menuBarMargins.top, menuBarMargins.right, menuBarMargins.bottom, menuBarMargins.left );
+	protected Component findHorizontalGlue( JMenuBar menuBar ) {
+		int count = menuBar.getComponentCount();
+		for( int i = count - 1; i >= 0; i-- ) {
+			Component c = menuBar.getComponent( i );
+			if( c instanceof Box.Filler && c.getMaximumSize().width >= Short.MAX_VALUE )
+				return c;
+		}
+		return null;
 	}
 
 	protected void menuBarChanged() {
@@ -654,8 +690,37 @@ debug*/
 			else
 				appIconBounds = iconBounds;
 		}
-		addNativeHitTestSpot( buttonPanel, false, hitTestSpots );
-		addNativeHitTestSpot( menuBarPlaceholder, true, hitTestSpots );
+
+		Rectangle r = getNativeHitTestSpot( buttonPanel );
+		if( r != null )
+			hitTestSpots.add( r );
+
+		r = getNativeHitTestSpot( menuBarPlaceholder );
+		if( r != null ) {
+			Component horizontalGlue = findHorizontalGlue( rootPane.getJMenuBar() );
+			if( horizontalGlue != null ) {
+				// If menu bar is embedded and contains a horizontal glue component,
+				// then split the hit test spot into two spots so that
+				// the glue component area can used to move the window.
+
+				Point glueLocation = SwingUtilities.convertPoint( horizontalGlue, 0, 0, window );
+				Rectangle r2;
+				if( getComponentOrientation().isLeftToRight() ) {
+					int trailingWidth = (r.x + r.width - HIT_TEST_SPOT_GROW) - glueLocation.x;
+					r.width -= trailingWidth;
+					r2 = new Rectangle( glueLocation.x + horizontalGlue.getWidth(), r.y, trailingWidth, r.height );
+				} else {
+					int leadingWidth = (glueLocation.x + horizontalGlue.getWidth()) - (r.x + HIT_TEST_SPOT_GROW);
+					r.x += leadingWidth;
+					r.width -= leadingWidth;
+					r2 = new Rectangle( glueLocation.x -leadingWidth, r.y, leadingWidth, r.height );
+				}
+				r2.grow( HIT_TEST_SPOT_GROW, HIT_TEST_SPOT_GROW );
+				hitTestSpots.add( r2 );
+			}
+
+			hitTestSpots.add( r );
+		}
 
 		FlatNativeWindowBorder.setTitleBarHeightAndHitTestSpots( window, titleBarHeight, hitTestSpots, appIconBounds );
 
@@ -667,27 +732,27 @@ debug*/
 debug*/
 	}
 
-	protected void addNativeHitTestSpot( JComponent c, boolean subtractMenuBarMargins, List<Rectangle> hitTestSpots ) {
+	protected Rectangle getNativeHitTestSpot( JComponent c ) {
 		Dimension size = c.getSize();
 		if( size.width <= 0 || size.height <= 0 )
-			return;
+			return null;
 
 		Point location = SwingUtilities.convertPoint( c, 0, 0, window );
 		Rectangle r = new Rectangle( location, size );
-		if( subtractMenuBarMargins )
-			r = FlatUIUtils.subtractInsets( r, UIScale.scale( getMenuBarMargins() ) );
 		// slightly increase rectangle so that component receives mouseExit events
-		r.grow( 2, 2 );
-		hitTestSpots.add( r );
+		r.grow( HIT_TEST_SPOT_GROW, HIT_TEST_SPOT_GROW );
+		return r;
 	}
 
+	private static final int HIT_TEST_SPOT_GROW = 2;
+
 /*debug
 	private int debugTitleBarHeight;
 	private List<Rectangle> debugHitTestSpots;
 	private Rectangle debugAppIconBounds;
 debug*/
 
-	//---- class TitlePaneBorder ----------------------------------------------
+	//---- class FlatTitlePaneBorder ------------------------------------------
 
 	protected class FlatTitlePaneBorder
 		extends AbstractBorder
@@ -729,7 +794,7 @@ debug*/
 
 		protected Border getMenuBarBorder() {
 			JMenuBar menuBar = rootPane.getJMenuBar();
-			return (menuBar != null && menuBar.isVisible() && isMenuBarEmbedded()) ? menuBar.getBorder() : null;
+			return hasVisibleEmbeddedMenuBar( menuBar ) ? menuBar.getBorder() : null;
 		}
 	}
 

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

@@ -688,9 +688,8 @@ TitledBorder.border = 1,1,1,1,$Separator.foreground
 TitlePane.useWindowDecorations = true
 TitlePane.menuBarEmbedded = true
 TitlePane.iconSize = 16,16
-TitlePane.iconMargins = 3,8,3,0
-TitlePane.menuBarMargins = 0,8,0,22
-TitlePane.titleMargins = 3,8,3,8
+TitlePane.iconMargins = 3,8,3,8
+TitlePane.titleMargins = 3,0,3,0
 TitlePane.buttonSize = 44,30
 TitlePane.buttonMaximizedHeight = 22
 TitlePane.closeIcon = com.formdev.flatlaf.icons.FlatWindowCloseIcon