InternalFrame: double-click on icon in internal frame title bar now closes the internal frame (issue #374)

CHANGELOG.md

@@ -1,13 +1,20 @@
 FlatLaf Change Log
 ==================
 
+## 1.6-SNAPSHOT
+
+#### New features and improvements
+
+- InternalFrame: Double-click on icon in internal frame title bar now closes the
+  internal frame. (issue #374)
+
+
 ## 1.5
 
 #### New features and improvements
 
 - SwingX: Added search and clear icons to `JXSearchField`. (issue #359)
 
-
 #### Fixed bugs
 
 - Button and TextComponent: Do not apply minimum width/height if margins are

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

@@ -21,6 +21,7 @@ import java.awt.Color;
 import java.awt.Dimension;
 import java.awt.Graphics;
 import java.awt.LayoutManager;
+import java.awt.Rectangle;
 import java.beans.PropertyChangeEvent;
 import java.beans.PropertyChangeListener;
 import javax.swing.BorderFactory;
@@ -146,6 +147,19 @@ public class FlatInternalFrameTitlePane
 		closeButton.setVisible( frame.isClosable() );
 	}
 
+	Rectangle getFrameIconBounds() {
+		Icon icon = titleLabel.getIcon();
+		if( icon == null )
+			return null;
+
+		int iconWidth = icon.getIconWidth();
+		int iconHeight = icon.getIconHeight();
+		boolean leftToRight = titleLabel.getComponentOrientation().isLeftToRight();
+		int x = titleLabel.getX() + (leftToRight ? 0 : (titleLabel.getWidth() - iconWidth));
+		int y = titleLabel.getY() + ((titleLabel.getHeight() - iconHeight) / 2);
+		return new Rectangle( x, y, iconWidth, iconHeight );
+	}
+
 	/**
 	 * Does nothing because FlatLaf internal frames do not have system menus.
 	 */

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

@@ -22,10 +22,13 @@ import java.awt.Component;
 import java.awt.Graphics;
 import java.awt.Graphics2D;
 import java.awt.Insets;
+import java.awt.Rectangle;
+import java.awt.event.MouseEvent;
 import javax.swing.JComponent;
 import javax.swing.JInternalFrame;
 import javax.swing.LookAndFeel;
 import javax.swing.UIManager;
+import javax.swing.event.MouseInputAdapter;
 import javax.swing.plaf.ComponentUI;
 import javax.swing.plaf.basic.BasicInternalFrameUI;
 
@@ -122,6 +125,11 @@ public class FlatInternalFrameUI
 		return new FlatWindowResizer.InternalFrameResizer( frame, this::getDesktopManager );
 	}
 
+	@Override
+	protected MouseInputAdapter createBorderListener( JInternalFrame w ) {
+		return new FlatBorderListener();
+	}
+
 	//---- class FlatInternalFrameBorder --------------------------------------
 
 	public static class FlatInternalFrameBorder
@@ -195,4 +203,26 @@ public class FlatInternalFrameUI
 			}
 		}
 	}
+
+	//---- class FlatBorderListener -------------------------------------------
+
+	protected class FlatBorderListener
+		extends BorderListener
+	{
+		@Override
+		public void mouseClicked( MouseEvent e ) {
+			if( e.getClickCount() == 2 && !frame.isIcon() &&
+				e.getSource() instanceof FlatInternalFrameTitlePane )
+			{
+				Rectangle iconBounds = ((FlatInternalFrameTitlePane)e.getSource()).getFrameIconBounds();
+				if( iconBounds != null && iconBounds.contains( e.getX(), e.getY() ) ) {
+					if( frame.isClosable() )
+						frame.doDefaultCloseAction();
+					return;
+				}
+			}
+
+			super.mouseClicked( e );
+		}
+	}
 }