Window decorations: "full window content" mode

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

@@ -257,13 +257,36 @@ public interface FlatClientProperties
 	String COMPONENT_FOCUS_OWNER = "JComponent.focusOwner";
 
 	/**
-	 * Specifies whether a component in an embedded menu bar should behave as caption
+	 * Specifies whether a component shown in a window title bar area should behave as caption
 	 * (left-click allows moving window, right-click shows window system menu).
-	 * The component does not receive mouse pressed/released/clicked/dragged events,
+	 * The caption component does not receive mouse pressed/released/clicked/dragged events,
 	 * but it gets mouse entered/exited/moved events.
 	 * <p>
+	 * Since 3.4, this client property also supports using a function that can check
+	 * whether a given location in the component should behave as caption.
+	 * Useful for components that do not use mouse input on whole component bounds.
+	 *
+	 * <pre>{@code
+	 * myComponent.putClientProperty( "JComponent.titleBarCaption",
+	 *     (Function<Point, Boolean>) pt -> {
+	 *         // parameter pt contains mouse location (in myComponent coordinates)
+	 *         // return true if the component is not interested in mouse input at the given location
+	 *         // return false if the component wants process mouse input at the given location
+	 *         // return null if the component children should be checked
+	 *         return ...; // check here
+	 *     } );
+	 * }</pre>
+	 * <b>Warning</b>:
+	 * <ul>
+	 *   <li>This function is invoked often when mouse is moved over window title bar area
+	 *       and should therefore return quickly.
+	 *   <li>This function is invoked on 'AWT-Windows' thread (not 'AWT-EventQueue' thread)
+	 *       while processing Windows messages.
+	 *       It <b>must not</b> change any component property or layout because this could cause a dead lock.
+	 * </ul>
+	 * <p>
 	 * <strong>Component</strong> {@link javax.swing.JComponent}<br>
-	 * <strong>Value type</strong> {@link java.lang.Boolean}
+	 * <strong>Value type</strong> {@link java.lang.Boolean} or {@link java.util.function.Function}&lt;Point, Boolean&gt;
 	 *
 	 * @since 2.5
 	 */
@@ -274,7 +297,7 @@ public interface FlatClientProperties
 
 	/**
 	 * Marks the panel as placeholder for the iconfify/maximize/close buttons
-	 * in fullWindowContent mode.
+	 * in fullWindowContent mode. See {@link #FULL_WINDOW_CONTENT}.
 	 * <p>
 	 * If fullWindowContent mode is enabled, the preferred size of the panel is equal
 	 * to the size of the iconfify/maximize/close buttons. Otherwise is is {@code 0,0}.
@@ -462,6 +485,32 @@ public interface FlatClientProperties
 	 */
 	String MENU_BAR_EMBEDDED = "JRootPane.menuBarEmbedded";
 
+	/**
+	 * Specifies whether the content pane (and the glass pane) should be extended
+	 * into the window title bar area
+	 * (requires enabled window decorations). Default is {@code false}.
+	 * <p>
+	 * On macOS, use client property {@code apple.awt.fullWindowContent}
+	 * (see <a href="https://www.formdev.com/flatlaf/macos/#full_window_content">macOS Full window content</a>).
+	 * <p>
+	 * Setting this enables/disables full window content
+	 * for the {@code JFrame} or {@code JDialog} that contains the root pane.
+	 * <p>
+	 * If {@code true}, the content pane (and the glass pane) is extended into
+	 * the title bar area. The window icon and title are hidden.
+	 * Only the iconfify/maximize/close buttons stay visible in the upper right corner
+	 * (and overlap the content pane).
+	 * <p>
+	 * The user can left-click-and-drag on the title bar area to move the window,
+	 * except when clicking on a component that processes mouse events (e.g. buttons or menus).
+	 * <p>
+	 * <strong>Component</strong> {@link javax.swing.JRootPane}<br>
+	 * <strong>Value type</strong> {@link java.lang.Boolean}
+	 *
+	 * @since 3.4
+	 */
+	String FULL_WINDOW_CONTENT = "FlatLaf.fullWindowContent";
+
 	/**
 	 * Contains the current bounds of the iconfify/maximize/close buttons
 	 * (in root pane coordinates) if fullWindowContent mode is enabled.

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

@@ -21,11 +21,12 @@
 import java.awt.Container;
 import java.awt.Graphics;
 import java.awt.Graphics2D;
+import java.awt.Point;
 import java.awt.Rectangle;
 import java.awt.Toolkit;
 import java.awt.Window;
 import java.beans.PropertyChangeListener;
-import java.util.List;
+import java.util.function.Predicate;
 import javax.swing.JDialog;
 import javax.swing.JFrame;
 import javax.swing.JRootPane;
@@ -218,13 +219,13 @@ public static void setHasCustomDecoration( Window window, boolean hasCustomDecor
 	}
 
 	static void setTitleBarHeightAndHitTestSpots( Window window, int titleBarHeight,
-		List<Rectangle> hitTestSpots, Rectangle appIconBounds, Rectangle minimizeButtonBounds,
+		Predicate<Point> captionHitTestCallback, Rectangle appIconBounds, Rectangle minimizeButtonBounds,
 		Rectangle maximizeButtonBounds, Rectangle closeButtonBounds )
 	{
 		if( !isSupported() )
 			return;
 
-		nativeProvider.updateTitleBarInfo( window, titleBarHeight, hitTestSpots,
+		nativeProvider.updateTitleBarInfo( window, titleBarHeight, captionHitTestCallback,
 			appIconBounds, minimizeButtonBounds, maximizeButtonBounds, closeButtonBounds );
 	}
 
@@ -270,7 +271,7 @@ public interface Provider
 	{
 		boolean hasCustomDecoration( Window window );
 		void setHasCustomDecoration( Window window, boolean hasCustomDecoration );
-		void updateTitleBarInfo( Window window, int titleBarHeight, List<Rectangle> hitTestSpots,
+		void updateTitleBarInfo( Window window, int titleBarHeight, Predicate<Point> captionHitTestCallback,
 			Rectangle appIconBounds, Rectangle minimizeButtonBounds, Rectangle maximizeButtonBounds,
 			Rectangle closeButtonBounds );
 

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

@@ -269,15 +269,28 @@ protected FlatTitlePane createTitlePane() {
 
 	// layer title pane under frame content layer to allow placing menu bar over title pane
 	protected final static Integer TITLE_PANE_LAYER = JLayeredPane.FRAME_CONTENT_LAYER - 1;
+	private final static Integer TITLE_PANE_MOUSE_LAYER = JLayeredPane.FRAME_CONTENT_LAYER - 2;
+
+	// for fullWindowContent mode, layer title pane over frame content layer to allow placing title bar buttons over content
+	/** @since 3.4 */
+	protected final static Integer TITLE_PANE_FULL_WINDOW_CONTENT_LAYER = JLayeredPane.FRAME_CONTENT_LAYER + 1;
+
+	private Integer getLayerForTitlePane() {
+		return isFullWindowContent( rootPane ) ? TITLE_PANE_FULL_WINDOW_CONTENT_LAYER : TITLE_PANE_LAYER;
+	}
 
 	protected void setTitlePane( FlatTitlePane newTitlePane ) {
 		JLayeredPane layeredPane = rootPane.getLayeredPane();
 
-		if( titlePane != null )
+		if( titlePane != null ) {
 			layeredPane.remove( titlePane );
+			layeredPane.remove( titlePane.mouseLayer );
+		}
 
-		if( newTitlePane != null )
-			layeredPane.add( newTitlePane, TITLE_PANE_LAYER );
+		if( newTitlePane != null ) {
+			layeredPane.add( newTitlePane, getLayerForTitlePane() );
+			layeredPane.add( newTitlePane.mouseLayer, TITLE_PANE_MOUSE_LAYER );
+		}
 
 		titlePane = newTitlePane;
 	}
@@ -430,6 +443,17 @@ public void propertyChange( PropertyChangeEvent e ) {
 					titlePane.titleBarColorsChanged();
 				break;
 
+			case FlatClientProperties.FULL_WINDOW_CONTENT:
+				if( titlePane != null ) {
+					rootPane.getLayeredPane().setLayer( titlePane, getLayerForTitlePane() );
+					titlePane.updateIcon();
+					titlePane.updateVisibility();
+					titlePane.updateFullWindowContentButtonsBoundsProperty();
+				}
+				FullWindowContentSupport.revalidatePlaceholders( rootPane );
+				rootPane.revalidate();
+				break;
+
 			case FlatClientProperties.FULL_WINDOW_CONTENT_BUTTONS_BOUNDS:
 				FullWindowContentSupport.revalidatePlaceholders( rootPane );
 				break;
@@ -471,11 +495,14 @@ public void propertyChange( PropertyChangeEvent e ) {
 		}
 	}
 
+	/** @since 3.4 */
+	protected static boolean isFullWindowContent( JRootPane rootPane ) {
+		return FlatClientProperties.clientPropertyBoolean( rootPane, FlatClientProperties.FULL_WINDOW_CONTENT, false );
+	}
+
 	protected static boolean isMenuBarEmbedded( JRootPane rootPane ) {
-		RootPaneUI ui = rootPane.getUI();
-		return ui instanceof FlatRootPaneUI &&
-			((FlatRootPaneUI)ui).titlePane != null &&
-			((FlatRootPaneUI)ui).titlePane.isMenuBarEmbedded();
+		FlatTitlePane titlePane = getTitlePane( rootPane );
+		return titlePane != null && titlePane.isMenuBarEmbedded();
 	}
 
 	/** @since 2.4 */
@@ -511,23 +538,21 @@ public Dimension maximumLayoutSize( Container parent ) {
 		private Dimension computeLayoutSize( Container parent, Function<Component, Dimension> getSizeFunc ) {
 			JRootPane rootPane = (JRootPane) parent;
 
-			Dimension titlePaneSize = (titlePane != null)
-				? getSizeFunc.apply( titlePane )
-				: new Dimension();
 			Dimension contentSize = (rootPane.getContentPane() != null)
 				? getSizeFunc.apply( rootPane.getContentPane() )
-				: rootPane.getSize();
+				: rootPane.getSize(); // same as in JRootPane.RootLayout.preferredLayoutSize()
 
 			int width = contentSize.width; // title pane width is not considered here
-			int height = titlePaneSize.height + contentSize.height;
+			int height = contentSize.height;
+			if( titlePane != null && !isFullWindowContent( rootPane ) )
+				height += getSizeFunc.apply( titlePane ).height;
 			if( titlePane == null || !titlePane.isMenuBarEmbedded() ) {
 				JMenuBar menuBar = rootPane.getJMenuBar();
-				Dimension menuBarSize = (menuBar != null && menuBar.isVisible())
-					? getSizeFunc.apply( menuBar )
-					: new Dimension();
-
-				width = Math.max( width, menuBarSize.width );
-				height += menuBarSize.height;
+				if( menuBar != null && menuBar.isVisible() ) {
+					Dimension menuBarSize = getSizeFunc.apply( menuBar );
+					width = Math.max( width, menuBarSize.width );
+					height += menuBarSize.height;
+				}
 			}
 
 			Insets insets = rootPane.getInsets();
@@ -552,12 +577,23 @@ public void layoutContainer( Container parent ) {
 			if( rootPane.getLayeredPane() != null )
 				rootPane.getLayeredPane().setBounds( x, y, width, height );
 
-			// title pane
+			// title pane (is a child of layered pane)
 			int nextY = 0;
 			if( titlePane != null ) {
 				int prefHeight = !isFullScreen ? titlePane.getPreferredSize().height : 0;
-				titlePane.setBounds( 0, 0, width, prefHeight );
-				nextY += prefHeight;
+				boolean isFullWindowContent = isFullWindowContent( rootPane );
+				if( isFullWindowContent && !UIManager.getBoolean( FlatTitlePane.KEY_DEBUG_SHOW_RECTANGLES ) ) {
+					// place title bar into top-right corner
+					int tw = Math.min( titlePane.getPreferredSize().width, width );
+					int tx = titlePane.getComponentOrientation().isLeftToRight() ? width - tw : 0;
+					titlePane.setBounds( tx, 0, tw, prefHeight );
+				} else
+					titlePane.setBounds( 0, 0, width, prefHeight );
+
+				titlePane.mouseLayer.setBounds( 0, 0, width, prefHeight );
+
+				if( !isFullWindowContent )
+					nextY += prefHeight;
 			}
 
 			// glass pane
@@ -568,21 +604,31 @@ public void layoutContainer( Container parent ) {
 				rootPane.getGlassPane().setBounds( x, y + offset, width, height - offset );
 			}
 
-			// menu bar
+			// menu bar (is a child of layered pane)
 			JMenuBar menuBar = rootPane.getJMenuBar();
 			if( menuBar != null && menuBar.isVisible() ) {
 				boolean embedded = !isFullScreen && titlePane != null && titlePane.isMenuBarEmbedded();
 				if( embedded ) {
 					titlePane.validate();
 					menuBar.setBounds( titlePane.getMenuBarBounds() );
 				} else {
+					int mx = 0;
+					int mw = width;
+					if( titlePane != null && isFullWindowContent( rootPane ) ) {
+						// make menu bar width smaller to avoid that it overlaps title bar buttons
+						int tw = Math.min( titlePane.getPreferredSize().width, width );
+						mw -= tw;
+						if( !titlePane.getComponentOrientation().isLeftToRight() )
+							mx = tw;
+					}
+
 					Dimension prefSize = menuBar.getPreferredSize();
-					menuBar.setBounds( 0, nextY, width, prefSize.height );
+					menuBar.setBounds( mx, nextY, mw, prefSize.height );
 					nextY += prefSize.height;
 				}
 			}
 
-			// content pane
+			// content pane (is a child of layered pane)
 			Container contentPane = rootPane.getContentPane();
 			if( contentPane != null )
 				contentPane.setBounds( 0, nextY, width, Math.max( height - nextY, 0 ) );

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

@@ -84,7 +84,7 @@
  */
 public class FlatSplitPaneUI
 	extends BasicSplitPaneUI
-	implements StyleableUI
+	implements StyleableUI, FlatTitlePane.TitleBarCaptionHitTest
 {
 	@Styleable protected String arrowType;
 	/** @since 3.3 */ @Styleable protected Color draggingColor;
@@ -227,6 +227,15 @@ private void paintDragDivider( Graphics g, int dividerLocation ) {
 			((FlatSplitPaneDivider)divider).paintStyle( g, x, y, width, height );
 	}
 
+	//---- interface FlatTitlePane.TitleBarCaptionHitTest ----
+
+	/** @since 3.4 */
+	@Override
+	public Boolean isTitleBarCaptionAt( int x, int y ) {
+		// necessary because BasicSplitPaneDivider adds some mouse listeners for dragging divider
+		return null; // check children
+	}
+
 	//---- class FlatSplitPaneDivider -----------------------------------------
 
 	protected class FlatSplitPaneDivider

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

@@ -182,7 +182,7 @@
  */
 public class FlatTabbedPaneUI
 	extends BasicTabbedPaneUI
-	implements StyleableUI
+	implements StyleableUI, FlatTitlePane.TitleBarCaptionHitTest
 {
 	// tab type
 	/** @since 2 */ protected static final int TAB_TYPE_UNDERLINED = 0;
@@ -2300,6 +2300,17 @@ private int rectsTotalHeight() {
 		return (rects[last].y + rects[last].height) - rects[0].y;
 	}
 
+	//---- interface FlatTitlePane.TitleBarCaptionHitTest ----
+
+	/** @since 3.4 */
+	@Override
+	public Boolean isTitleBarCaptionAt( int x, int y ) {
+		if( tabForCoordinate( tabPane, x, y ) >= 0 )
+			return false;
+
+		return null; // check children
+	}
+
 	//---- class TabCloseButton -----------------------------------------------
 
 	private static class TabCloseButton