libjava/classpath/javax/swing/CellRendererPane.java

   1 /* CellRendererPane.java --
   2    Copyright (C) 2002, 2004, 2006, Free Software Foundation, Inc.
   3
   4 This file is part of GNU Classpath.
   5
   6 GNU Classpath is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU Classpath is distributed in the hope that it will be useful, but
  12 WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Classpath; see the file COPYING.  If not, write to the
  18 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  19 02110-1301 USA.
  20
  21 Linking this library statically or dynamically with other modules is
  22 making a combined work based on this library.  Thus, the terms and
  23 conditions of the GNU General Public License cover the whole
  24 combination.
  25
  26 As a special exception, the copyright holders of this library give you
  27 permission to link this library with independent modules to produce an
  28 executable, regardless of the license terms of these independent
  29 modules, and to copy and distribute the resulting executable under
  30 terms of your choice, provided that you also meet, for each linked
  31 independent module, the terms and conditions of the license of that
  32 module.  An independent module is a module which is not derived from
  33 or based on this library.  If you modify this library, you may extend
  34 this exception to your version of the library, but you are not
  35 obligated to do so.  If you do not wish to do so, delete this
  36 exception statement from your version. */
  37
  38
  39 package javax.swing;
  40
  41 import java.awt.Component;
  42 import java.awt.Container;
  43 import java.awt.Graphics;
  44 import java.awt.Rectangle;
  45
  46 import javax.accessibility.Accessible;
  47 import javax.accessibility.AccessibleContext;
  48 import javax.accessibility.AccessibleRole;
  49
  50 /**
  51  * Paints the cells of JList, JTable and JTree.
  52  * It intercepts the usual paint tree, so that we don't walk up and
  53  * repaint everything.
  54  *
  55  * @author Andrew Selkirk
  56  */
  57 public class CellRendererPane extends Container implements Accessible
  58 {
  59   private static final long serialVersionUID = -7642183829532984273L;
  60
  61   /**
  62    * Provides accessibility support for CellRendererPanes.
  63    */
  64   protected class AccessibleCellRendererPane extends AccessibleAWTContainer
  65   {
  66     private static final long serialVersionUID = -8981090083147391074L;
  67
  68     /**
  69      * Constructor AccessibleCellRendererPane
  70      */
  71     protected AccessibleCellRendererPane()
  72     {
  73       // Nothing to do here.
  74     }
  75
  76     /**
  77      * getAccessibleRole
  78      * @return AccessibleRole
  79      */
  80     public AccessibleRole getAccessibleRole()
  81     {
  82       return AccessibleRole.PANEL;
  83     }
  84   }
  85
  86   /**
  87    * accessibleContext
  88    */
  89   protected AccessibleContext accessibleContext = null;
  90
  91   /**
  92    * Constructs a new CellRendererPane.
  93    */
  94   public CellRendererPane()
  95   {
  96     setVisible(false);
  97   }
  98
  99   /**
 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 }