Window decorations: added window icon (issues #47 and #82)

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

@@ -19,8 +19,10 @@ package com.formdev.flatlaf.ui;
 import java.awt.BorderLayout;
 import java.awt.Color;
 import java.awt.Dialog;
+import java.awt.Dimension;
 import java.awt.Frame;
 import java.awt.Graphics;
+import java.awt.Image;
 import java.awt.Window;
 import java.awt.event.ActionListener;
 import java.awt.event.MouseEvent;
@@ -29,6 +31,7 @@ import java.awt.event.WindowAdapter;
 import java.awt.event.WindowEvent;
 import java.beans.PropertyChangeEvent;
 import java.beans.PropertyChangeListener;
+import java.util.List;
 import javax.accessibility.AccessibleContext;
 import javax.swing.BorderFactory;
 import javax.swing.BoxLayout;
@@ -39,7 +42,6 @@ import javax.swing.JPanel;
 import javax.swing.JRootPane;
 import javax.swing.SwingUtilities;
 import javax.swing.UIManager;
-import com.formdev.flatlaf.util.UIScale;
 
 /**
  * Provides the Flat LaF title bar.
@@ -48,6 +50,9 @@ import com.formdev.flatlaf.util.UIScale;
  * @uiDefault TitlePane.inactiveBackground					Color
  * @uiDefault TitlePane.foreground							Color
  * @uiDefault TitlePane.inactiveForeground					Color
+ * @uiDefault TitlePane.iconSize							Dimension
+ * @uiDefault TitlePane.iconMargins							Insets
+ * @uiDefault TitlePane.titleMargins						Insets
  * @uiDefault TitlePane.closeIcon							Icon
  * @uiDefault TitlePane.iconifyIcon							Icon
  * @uiDefault TitlePane.maximizeIcon						Icon
@@ -63,8 +68,11 @@ class FlatTitlePane
 	private final Color activeForeground = UIManager.getColor( "TitlePane.foreground" );
 	private final Color inactiveForeground = UIManager.getColor( "TitlePane.inactiveForeground" );
 
+	private final Dimension iconSize = UIManager.getDimension( "TitlePane.iconSize" );
+
 	private final JRootPane rootPane;
 
+	private JLabel iconLabel;
 	private JLabel titleLabel;
 	private JPanel buttonPanel;
 	private JButton iconifyButton;
@@ -85,12 +93,15 @@ class FlatTitlePane
 	}
 
 	private void addSubComponents() {
+		iconLabel = new JLabel();
 		titleLabel = new JLabel();
+		iconLabel.setBorder( new FlatEmptyBorder( UIManager.getInsets( "TitlePane.iconMargins" ) ) );
 		titleLabel.setBorder( new FlatEmptyBorder( UIManager.getInsets( "TitlePane.titleMargins" ) ) );
 
 		createButtons();
 
-		setLayout( new BorderLayout( UIScale.scale( 4 ), 0 ) );
+		setLayout( new BorderLayout() );
+		add( iconLabel, BorderLayout.WEST );
 		add( titleLabel, BorderLayout.CENTER );
 		add( buttonPanel, BorderLayout.EAST );
 	}
@@ -157,6 +168,26 @@ class FlatTitlePane
 		}
 	}
 
+	private void updateIcon() {
+		// get window images
+		List<Image> images = window.getIconImages();
+		if( images.isEmpty() ) {
+			// search in owners
+			for( Window owner = window.getOwner(); owner != null; owner = owner.getOwner() ) {
+				images = owner.getIconImages();
+				if( !images.isEmpty() )
+					break;
+			}
+		}
+
+		// show/hide icon
+		boolean hasImages = !images.isEmpty();
+		iconLabel.setVisible( hasImages );
+
+		if( hasImages )
+			iconLabel.setIcon( FlatTitlePaneIcon.create( images, iconSize ) );
+	}
+
 	@Override
 	public void addNotify() {
 		super.addNotify();
@@ -167,6 +198,7 @@ class FlatTitlePane
 		if( window != null ) {
 			frameStateChanged();
 			activeChanged( window.isActive() );
+			updateIcon();
 			titleLabel.setText( getWindowTitle() );
 			installWindowListeners();
 		}
@@ -260,6 +292,10 @@ class FlatTitlePane
 					if( window instanceof Frame )
 						frameStateChanged();
 					break;
+
+				case "iconImage":
+					updateIcon();
+					break;
 			}
 		}
 

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

@@ -0,0 +1,70 @@
+/*
+ * Copyright 2020 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
+ *
+ *     https://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.ui;
+
+import java.awt.Dimension;
+import java.awt.Image;
+import java.util.ArrayList;
+import java.util.List;
+import javax.swing.Icon;
+import javax.swing.ImageIcon;
+import com.formdev.flatlaf.util.MultiResolutionImageSupport;
+import com.formdev.flatlaf.util.ScaledImageIcon;
+
+/**
+ * @author Karl Tauber
+ */
+class FlatTitlePaneIcon
+	extends ScaledImageIcon
+{
+	static Icon create( List<Image> images, Dimension size ) {
+		// collect all images including multi-resolution variants
+		List<Image> allImages = new ArrayList<>();
+		for( Image image : images ) {
+			if( MultiResolutionImageSupport.isMultiResolutionImage( image ) )
+				allImages.addAll( MultiResolutionImageSupport.getResolutionVariants( image ) );
+			else
+				allImages.add( image );
+		}
+
+		// sort images by size
+		allImages.sort( (image1, image2) -> {
+			return image1.getWidth( null ) - image2.getWidth( null );
+		} );
+
+		// create icon
+		return new FlatTitlePaneIcon( allImages, size );
+	}
+
+	private final List<Image> images;
+
+	FlatTitlePaneIcon( List<Image> images, Dimension size ) {
+		super( new ImageIcon( images.get( 0 ) ), size.width, size.height );
+		this.images = images;
+	}
+
+	@Override
+	protected Image getResolutionVariant( int destImageWidth, int destImageHeight ) {
+		for( Image image : images ) {
+			if( destImageWidth <= image.getWidth( null ) &&
+				destImageHeight <= image.getHeight( null ) )
+			  return image;
+		}
+
+		return images.get( images.size() - 1 );
+	}
+}

flatlaf-core/src/main/java/com/formdev/flatlaf/util/ScaledImageIcon.java

@@ -37,30 +37,38 @@ public class ScaledImageIcon
 	implements Icon
 {
 	private final ImageIcon imageIcon;
+	private final int iconWidth;
+	private final int iconHeight;
 
 	private double lastSystemScaleFactor;
 	private float lastUserScaleFactor;
 	private Image lastImage;
 
 	public ScaledImageIcon( ImageIcon imageIcon ) {
+		this( imageIcon, imageIcon.getIconWidth(), imageIcon.getIconHeight() );
+	}
+
+	public ScaledImageIcon( ImageIcon imageIcon, int iconWidth, int iconHeight ) {
 		this.imageIcon = imageIcon;
+		this.iconWidth = iconWidth;
+		this.iconHeight = iconHeight;
 	}
 
 	@Override
 	public int getIconWidth() {
-		return UIScale.scale( imageIcon.getIconWidth() );
+		return UIScale.scale( iconWidth );
 	}
 
 	@Override
 	public int getIconHeight() {
-		return UIScale.scale( imageIcon.getIconHeight() );
+		return UIScale.scale( iconHeight );
 	}
 
 	@Override
 	public void paintIcon( Component c, Graphics g, int x, int y ) {
 /*debug
 		g.setColor( Color.red );
-		g.drawRect( x, y, getIconWidth(), getIconHeight() );
+		g.drawRect( x, y, getIconWidth() - 1, getIconHeight() - 1 );
 debug*/
 
 		// scale factor
@@ -69,7 +77,7 @@ debug*/
 		double scaleFactor = systemScaleFactor * userScaleFactor;
 
 		// paint input image icon if not necessary to scale
-		if( scaleFactor == 1 ) {
+		if( scaleFactor == 1 && iconWidth == imageIcon.getIconWidth() && iconHeight == imageIcon.getIconHeight() ) {
 			imageIcon.paintIcon( c, g, x, y );
 			return;
 		}
@@ -84,12 +92,11 @@ debug*/
 		}
 
 		// destination image size
-		int destImageWidth = (int) Math.round( imageIcon.getIconWidth() * scaleFactor );
-		int destImageHeight = (int) Math.round( imageIcon.getIconHeight() * scaleFactor );
+		int destImageWidth = (int) Math.round( iconWidth * scaleFactor );
+		int destImageHeight = (int) Math.round( iconHeight * scaleFactor );
 
 		// get resolution variant of image if it is a multi-resolution image
-		Image image = MultiResolutionImageSupport.getResolutionVariant(
-			imageIcon.getImage(), destImageWidth, destImageHeight );
+		Image image = getResolutionVariant( destImageWidth, destImageHeight );
 
 		// size of image
 		int imageWidth = image.getWidth( null );
@@ -124,6 +131,11 @@ debug*/
 		paintLastImage( g, x, y );
 	}
 
+	protected Image getResolutionVariant( int destImageWidth, int destImageHeight ) {
+		return MultiResolutionImageSupport.getResolutionVariant(
+			imageIcon.getImage(), destImageWidth, destImageHeight );
+	}
+
 	private void paintLastImage( Graphics g, int x, int y ) {
 		if( lastSystemScaleFactor > 1 ) {
 			HiDPIUtils.paintAtScale1x( (Graphics2D) g, x, y, 100, 100, // width and height are not used

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

@@ -576,6 +576,8 @@ TitledBorder.border=1,1,1,1,$Separator.foreground
 
 #---- TitlePane ----
 
+TitlePane.iconSize=16,16
+TitlePane.iconMargins=3,8,3,0
 TitlePane.titleMargins=3,8,3,8
 TitlePane.closeIcon=$InternalFrame.closeIcon
 TitlePane.iconifyIcon=$InternalFrame.iconifyIcon