001    /*
002     * $Id: PainterGlasspane.java 3235 2009-02-01 15:01:07Z rah003 $
003     *
004     * Copyright 2006 Sun Microsystems, Inc., 4150 Network Circle,
005     * Santa Clara, California 95054, U.S.A. All rights reserved.
006     *
007     * This library is free software; you can redistribute it and/or
008     * modify it under the terms of the GNU Lesser General Public
009     * License as published by the Free Software Foundation; either
010     * version 2.1 of the License, or (at your option) any later version.
011     *
012     * This library is distributed in the hope that it will be useful,
013     * but WITHOUT ANY WARRANTY; without even the implied warranty of
014     * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
015     * Lesser General Public License for more details.
016     *
017     * You should have received a copy of the GNU Lesser General Public
018     * License along with this library; if not, write to the Free Software
019     * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
020     */
021    
022    
023    package org.jdesktop.swingx.painter;
024    
025    import javax.swing.*;
026    import java.awt.*;
027    import java.util.ArrayList;
028    import java.util.List;
029    
030    /**
031     * This is a glasspane which will draw the specified painter on
032     * top of the specified target components. The PainterGlasspane would
033     * commonly be used for drawing a translucent overlay or icon badge on top
034     * of components which are invalid, indicating to the user what the problem
035     * is. 
036     * 
037     * The PainterGlasspane can also be used to apply a Painter on top of a component
038     * which does not already support painters on it's own.
039     * 
040     * @author joshy
041     */
042    public class PainterGlasspane extends JComponent {
043        private Painter painter;
044        private List<JComponent>targets;
045        
046        /** Creates a new instance of ValidationOverlay */
047        public PainterGlasspane() {
048            targets = new ArrayList<JComponent>();
049        }
050        
051        public void addTarget(JComponent comp) {
052            targets.add(comp);
053            repaint();
054        }
055        public void removeTarget(JComponent comp) {
056            targets.remove(comp);
057            repaint();
058        }
059        
060        protected void paintComponent(Graphics gfx) {
061            Graphics2D g = (Graphics2D)gfx;
062            if(getPainter() != null) {
063                for(JComponent target : targets) {
064                    Point offset = calcOffset(target);
065                    g.translate(offset.x,offset.y);
066                    getPainter().paint(g, target, target.getWidth(), target.getHeight());
067                    g.translate(-offset.x,-offset.y);
068                }
069            }
070        }
071    
072        private Point calcOffset(JComponent target) {
073            if(target == null) {
074                return new Point(0,0);
075            }
076            // if the parent is the top then we must be the rootpane?
077            if(target.getParent() == SwingUtilities.getWindowAncestor(target)) {
078                return new Point(0,0);
079            }
080            
081            Point parent = calcOffset((JComponent)target.getParent());
082            Point self = target.getLocation();
083            return new Point(parent.x + self.x, parent.y + self.y);
084        }
085    
086        public Painter getPainter() {
087            return painter;
088        }
089    
090        public void setPainter(Painter painter) {
091            Painter old = getPainter();
092            this.painter = painter;
093            firePropertyChange("painter", old, getPainter());
094            repaint();
095        }
096    }