1 /*

     2  * Copyright 1997-2008 Sun Microsystems, Inc.  All Rights Reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.  Sun designates this

     8  * particular file as subject to the "Classpath" exception as provided

     9  * by Sun in the LICENSE file that accompanied this code.

    10  *

    11  * This code is distributed in the hope that it will be useful, but WITHOUT

    12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    14  * version 2 for more details (a copy is included in the LICENSE file that

    15  * accompanied this code).

    16  *

    17  * You should have received a copy of the GNU General Public License version

    18  * 2 along with this work; if not, write to the Free Software Foundation,

    19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    20  *

    21  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

    22  * CA 95054 USA or visit www.sun.com if you need additional information or

    23  * have any questions.

    24  */

    25 

    26 package javax.swing.plaf.basic;

    27 

    28 import javax.swing.*;

    29 import java.awt.*;

    30 import java.awt.event.*;

    31 import java.beans.*;

    32 

    33 /**

    34  * DesktopIconMover is intended to move desktop icon

    35  * when parent window is resized.

    36  */

    37 class DesktopIconMover implements ComponentListener, PropertyChangeListener {

    38     private Component parent;

    39     private JInternalFrame frame; // if not null, DesktopIconMover(frame)

    40                                   // constructor was used

    41     private JInternalFrame.JDesktopIcon icon;

    42     private Rectangle parentBounds;

    43     private boolean componentListenerAdded = false;

    44 

    45     public DesktopIconMover(JInternalFrame frame) {

    46         if (frame == null) {

    47             throw new NullPointerException("Frame cannot be null");

    48         }

    49         this.frame = frame;

    50         this.icon = frame.getDesktopIcon();

    51         if (icon == null) {

    52             throw new NullPointerException(

    53                     "frame.getDesktopIcon() cannot be null");

    54         }

    55         this.parent = frame.getParent();

    56         if (this.parent != null) {

    57             parentBounds = this.parent.getBounds();

    58         }

    59     }

    60 

    61     public DesktopIconMover(JInternalFrame.JDesktopIcon icon) {

    62         if (icon == null) {

    63             throw new NullPointerException("Icon cannot be null");

    64         }

    65         this.icon = icon;

    66         this.parent = icon.getParent();

    67         if (this.parent != null) {

    68             parentBounds = this.parent.getBounds();

    69         }

    70     }

    71 

    72     public void installListeners() {

    73         if (frame != null) {

    74             frame.addPropertyChangeListener(this);

    75         } else {

    76             icon.addPropertyChangeListener(this);

    77         }

    78         addComponentListener();

    79     }

    80 

    81     public void uninstallListeners() {

    82         if (frame != null) {

    83             frame.removePropertyChangeListener(this);

    84         } else {

    85             icon.removePropertyChangeListener(this);

    86         }

    87         removeComponentListener();

    88     }

    89 

    90     public void propertyChange(PropertyChangeEvent evt) {

    91         String propName = evt.getPropertyName();

    92         if ("ancestor".equals(propName)) {

    93             Component newAncestor = (Component) evt.getNewValue();

    94 

    95             // Remove component listener if parent is changing

    96             Component probablyNewParent = getCurrentParent();

    97             if ((probablyNewParent != null) &&

    98                     (!probablyNewParent.equals(parent))) {

    99                 removeComponentListener();

   100                 parent = probablyNewParent;

   101             }

   102 

   103             if (newAncestor == null) {

   104                 removeComponentListener();

   105             } else {

   106                 addComponentListener();

   107             }

   108 

   109             // Update parentBounds

   110             if (parent != null) {

   111                 parentBounds = parent.getBounds();

   112             } else {

   113                 parentBounds = null;

   114             }

   115         } else if (JInternalFrame.IS_CLOSED_PROPERTY.equals(propName)) {

   116             removeComponentListener();

   117         }

   118     }

   119 

   120     private void addComponentListener() {

   121         if (!componentListenerAdded && (parent != null)) {

   122             parent.addComponentListener(this);

   123             componentListenerAdded = true;

   124         }

   125     }

   126 

   127     private void removeComponentListener() {

   128         if ((parent != null) && componentListenerAdded) {

   129             parent.removeComponentListener(this);

   130             componentListenerAdded = false;

   131         }

   132     }

   133 

   134     private Component getCurrentParent() {

   135         if (frame != null) {

   136             return frame.getParent();

   137         } else {

   138             return icon.getParent();

   139         }

   140     }

   141 

   142     public void componentResized(ComponentEvent e) {

   143         if ((parent == null) || (parentBounds == null)) {

   144             return;

   145         }

   146 

   147         Rectangle parentNewBounds = parent.getBounds();

   148         if ((parentNewBounds == null) || parentNewBounds.equals(parentBounds)) {

   149             return;

   150         }

   151 

   152         // Move desktop icon only in up-down direction

   153         int newIconY = icon.getLocation().y +

   154                 (parentNewBounds.height - parentBounds.height);

   155         icon.setLocation(icon.getLocation().x, newIconY);

   156 

   157         parentBounds = parentNewBounds;

   158     }

   159 

   160     public void componentMoved(ComponentEvent e) {

   161     }

   162 

   163     public void componentShown(ComponentEvent e) {

   164     }

   165 

   166     public void componentHidden(ComponentEvent e) {

   167     }

   168 }