001/* CellRendererPane.java --
002   Copyright (C) 2002, 2004, 2006, Free Software Foundation, Inc.
003
004This file is part of GNU Classpath.
005
006GNU Classpath is free software; you can redistribute it and/or modify
007it under the terms of the GNU General Public License as published by
008the Free Software Foundation; either version 2, or (at your option)
009any later version.
010
011GNU Classpath is distributed in the hope that it will be useful, but
012WITHOUT ANY WARRANTY; without even the implied warranty of
013MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014General Public License for more details.
015
016You should have received a copy of the GNU General Public License
017along with GNU Classpath; see the file COPYING.  If not, write to the
018Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
01902110-1301 USA.
020
021Linking this library statically or dynamically with other modules is
022making a combined work based on this library.  Thus, the terms and
023conditions of the GNU General Public License cover the whole
024combination.
025
026As a special exception, the copyright holders of this library give you
027permission to link this library with independent modules to produce an
028executable, regardless of the license terms of these independent
029modules, and to copy and distribute the resulting executable under
030terms of your choice, provided that you also meet, for each linked
031independent module, the terms and conditions of the license of that
032module.  An independent module is a module which is not derived from
033or based on this library.  If you modify this library, you may extend
034this exception to your version of the library, but you are not
035obligated to do so.  If you do not wish to do so, delete this
036exception statement from your version. */
037
038
039package javax.swing;
040
041import java.awt.Component;
042import java.awt.Container;
043import java.awt.Graphics;
044import java.awt.Rectangle;
045
046import javax.accessibility.Accessible;
047import javax.accessibility.AccessibleContext;
048import javax.accessibility.AccessibleRole;
049
050/**
051 * Paints the cells of JList, JTable and JTree.
052 * It intercepts the usual paint tree, so that we don't walk up and
053 * repaint everything.
054 *
055 * @author Andrew Selkirk
056 */
057public class CellRendererPane extends Container implements Accessible
058{
059  private static final long serialVersionUID = -7642183829532984273L;
060
061  /**
062   * Provides accessibility support for CellRendererPanes.
063   */
064  protected class AccessibleCellRendererPane extends AccessibleAWTContainer
065  {
066    private static final long serialVersionUID = -8981090083147391074L;
067
068    /**
069     * Constructor AccessibleCellRendererPane
070     */
071    protected AccessibleCellRendererPane()
072    {
073      // Nothing to do here.
074    }
075
076    /**
077     * getAccessibleRole
078     * @return AccessibleRole
079     */
080    public AccessibleRole getAccessibleRole()
081    {
082      return AccessibleRole.PANEL;
083    }
084  }
085
086  /**
087   * accessibleContext
088   */
089  protected AccessibleContext accessibleContext = null;
090
091  /**
092   * Constructs a new CellRendererPane.
093   */
094  public CellRendererPane()
095  {
096    setVisible(false);
097  }
098
099  /**
100   * Should not be called.
101   *
102   * @param graphics not used here
103   */
104  public void update(Graphics graphics)
105  {
106    //Nothing to do here.
107  }
108
109  /**
110   * Despite normal behaviour this does <em>not</em> cause the container
111   * to be invalidated. This prevents propagating up the paint tree.
112   */
113  public void invalidate()
114  {
115    // Overridden to do nothing.
116  }
117
118  /**
119   * Should not be called.
120   *
121   * @param graphics not used here
122   */
123  public void paint(Graphics graphics)
124  {
125    // Overridden to do nothing.
126  }
127
128  /**
129   * Overridden to check if a component is already a child of this Container.
130   * If it's already a child, nothing is done. Otherwise we pass this to
131   * <code>super.addImpl()</code>.
132   *
133   * @param c the component to add
134   * @param constraints not used here
135   * @param index not used here
136   */
137  protected void addImpl(Component c, Object constraints, int index)
138  {
139    if (!isAncestorOf(c))
140      {
141        super.addImpl(c, constraints, index);
142      }
143  }
144
145  /**
146   * Paints the specified component <code>c</code> on the {@link Graphics}
147   * context <code>graphics</code>. The Graphics context is tranlated to
148   * (x,y) and the components bounds are set to (w,h). If
149   * <code>shouldValidate</code>
150   * is set to true, then the component is validated before painting.
151   *
152   * @param graphics the graphics context to paint on
153   * @param c the component to be painted
154   * @param p the parent of the component
155   * @param x the X coordinate of the upper left corner where c should
156            be painted
157   * @param y the Y coordinate of the upper left corner where c should
158            be painted
159   * @param w the width of the components drawing area
160   * @param h the height of the components drawing area
161   * @param shouldValidate if <code>c</code> should be validated before
162   *        painting
163   */
164  public void paintComponent(Graphics graphics, Component c,
165                             Container p, int x, int y, int w, int h,
166                             boolean shouldValidate)
167  {
168    // reparent c
169    addImpl(c, null, 0);
170
171    Rectangle oldClip = graphics.getClipBounds();
172    boolean translated = false;
173    try
174      {
175        // translate to (x,y)
176        graphics.translate(x, y);
177        translated = true;
178        graphics.clipRect(0, 0, w, h);
179        // set bounds of c
180        c.setBounds(0, 0, w, h);
181
182        // validate if necessary
183        if (shouldValidate)
184          {
185            c.validate();
186          }
187
188        // paint component
189        c.paint(graphics);
190      }
191    finally
192      {
193        // untranslate g
194        if (translated)
195          graphics.translate(-x, -y);
196        graphics.setClip(oldClip);
197      }
198  }
199
200  /**
201   * Paints the specified component <code>c</code> on the {@link Graphics}
202   * context <code>graphics</code>. The Graphics context is tranlated to (x,y)
203   * and the components bounds are set to (w,h). The component is <em>not</em>
204   * validated before painting.
205   *
206   * @param graphics the graphics context to paint on
207   * @param c the component to be painted
208   * @param p the parent of the component
209   * @param x the X coordinate of the upper left corner where c should
210            be painted
211   * @param y the Y coordinate of the upper left corner where c should
212            be painted
213   * @param w the width of the components drawing area
214   * @param h the height of the components drawing area
215   */
216  public void paintComponent(Graphics graphics, Component c,
217                             Container p, int x, int y, int w, int h)
218  {
219    paintComponent(graphics, c, p, x, y, w, h, false);
220  }
221
222  /**
223   * Paints the specified component <code>c</code> on the {@link Graphics}
224   * context <code>g</code>. The Graphics context is tranlated to (r.x,r.y) and
225   * the components bounds are set to (r.width,r.height).
226   * The component is <em>not</em>
227   * validated before painting.
228   *
229   * @param graphics the graphics context to paint on
230   * @param c the component to be painted
231   * @param p the component on which we paint
232   * @param r the bounding rectangle of c
233   */
234  public void paintComponent(Graphics graphics, Component c,
235                             Container p, Rectangle r)
236  {
237    paintComponent(graphics, c, p, r.x, r.y, r.width, r.height);
238  }
239
240  /**
241   * getAccessibleContext <em>TODO</em>
242   * @return AccessibleContext
243   */
244  public AccessibleContext getAccessibleContext()
245  {
246    if (accessibleContext == null)
247      accessibleContext = new AccessibleCellRendererPane();
248
249    return accessibleContext;
250  }
251}