gomp-20050608-branch/libjava/classpath/javax/swing/Box.java

   1 /* Box.java --
   2    Copyright (C) 2002, 2004 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.AWTError;
  42 import java.awt.Component;
  43 import java.awt.Container;
  44 import java.awt.Dimension;
  45 import java.awt.LayoutManager;
  46
  47 import javax.accessibility.Accessible;
  48 import javax.accessibility.AccessibleContext;
  49 import javax.accessibility.AccessibleRole;
  50
  51 /**
  52  * A component that uses a {@link BoxLayout} as Layout Manager.
  53  *
  54  * In addition to that, this class provides a set of static methods for
  55  * creating some filler components ('struts' and 'glue') for use in
  56  * containers that are laid out using BoxLayout.
  57  *
  58  * @author Ronald Veldema (rveldema@cs.vu.nl)
  59  */
  60 public class Box extends JComponent implements Accessible
  61 {
  62   private static final long serialVersionUID = 1525417495883046342L;
  63
  64   /**
  65    * Provides accessibility support for <code>Box</code>es.
  66    */
  67   protected class AccessibleBox extends Container.AccessibleAWTContainer
  68   {
  69     private static final long serialVersionUID = -7775079816389931944L;
  70
  71     protected AccessibleBox()
  72     {
  73       // Nothing to do here.
  74     }
  75
  76     public AccessibleRole getAccessibleRole()
  77     {
  78       return null;
  79     }
  80   }
  81
  82   /**
  83    * A component that servers as a filler in BoxLayout controlled containers.
  84    */
  85   public static class Filler extends JComponent implements Accessible
  86   {
  87     private static final long serialVersionUID = -1204263191910183998L;
  88
  89     /**
  90      * Provides accessibility support for <code>Box.Filler</code>.
  91      */
  92     protected class AccessibleBoxFiller
  93       extends Component.AccessibleAWTComponent
  94     {
  95       private static final long serialVersionUID = 164963348357479321L;
  96
  97       protected AccessibleBoxFiller()
  98       {
  99         // Nothing to do here.
 100       }
 101
 102       public AccessibleRole getAccessibleRole()
 103       {
 104         return null;
 105       }
 106     }
 107
 108     private transient Dimension min, pref, max;
 109
 110     /**
 111      * Creates a new instance of Filler.
 112      *
 113      * @param min the minimum size of the filler.
 114      * @param pref the preferred size of the filler.
 115      * @param max the maximum size of the filler.
 116      */
 117     public Filler(Dimension min, Dimension pref, Dimension max)
 118     {
 119       changeShape(min, pref, max);
 120     }
 121
 122     /**
 123      * Changes the dimensions of this Filler.
 124      *
 125      * @param min the new minimum size of the filler.
 126      * @param pref the new preferred size of the filler.
 127      * @param max the new maximum size of the filler.
 128      */
 129     public void changeShape(Dimension min, Dimension pref, Dimension max)
 130     {
 131       this.min = min;
 132       this.pref = pref;
 133       this.max = max;
 134     }
 135
 136     public AccessibleContext getAccessibleContext()
 137     {
 138       if (accessibleContext == null)
 139         accessibleContext = new AccessibleBoxFiller();
 140       return accessibleContext;
 141     }
 142
 143     /**
 144      * Returns the maximum size of this Filler.
 145      *
 146      * @return the maximum size of this Filler.
 147      */
 148     public Dimension getMaximumSize()
 149     {
 150       return max;
 151     }
 152
 153     /**
 154      * Returns the minimum size of this Filler.
 155      *
 156      * @return the minimum size of this Filler.
 157      */
 158     public Dimension getMinimumSize()
 159     {
 160       return min;
 161     }
 162
 163     /**
 164      * Returns the preferred size of this Filler.
 165      *
 166      * @return the preferred size of this Filler.
 167      */
 168     public Dimension getPreferredSize()
 169     {
 170       return pref;
 171     }
 172   }
 173
 174   /**
 175    * Creates a new Box component, that lays out its children according
 176    * to the <code>axis</code> parameter.
 177    *
 178    * @param axis the orientation of the BoxLayout.
 179    *
 180    * @see BoxLayout#X_AXIS
 181    * @see BoxLayout#Y_AXIS
 182    * @see BoxLayout#LINE_AXIS
 183    * @see BoxLayout#PAGE_AXIS
 184    */
 185   public Box(int axis)
 186   {
 187     super.setLayout(new BoxLayout(this, axis));
 188   }
 189
 190   /**
 191    * Creates a filler component which acts as glue between components.
 192    * It does not take space unless some extra space is available. If extra
 193    * space is available, this component can expand in both X and Y directions.
 194    *
 195    * @return a glue-like filler component.
 196    */
 197   public static Component createGlue()
 198   {
 199     Filler glue = new Filler(new Dimension(0,0), new Dimension(0,0),
 200                              new Dimension(Short.MAX_VALUE,Short.MAX_VALUE)
 201                              );
 202     return glue;
 203   }
 204
 205   public static Box createHorizontalBox()
 206   {
 207     return new Box(BoxLayout.X_AXIS);
 208   }
 209
 210   /**
 211    * Creates a filler component which acts as glue between components.
 212    * It does not take space unless some extra space is available. If extra
 213    * space is available, this component can expand in the X direction.
 214    *
 215    * @return a glue-like filler component.
 216    */
 217   public static Component createHorizontalGlue()
 218   {
 219     Filler glue = new Filler(new Dimension(0,0), new Dimension(0,0),
 220                              new Dimension(Short.MAX_VALUE, 0)
 221                              );
 222     return glue;
 223   }
 224
 225   /**
 226    * Creates a filler component which acts as strut between components.
 227    * It will fill exactly the specified horizontal size.
 228    *
 229    * @param width the width of this strut in pixels.
 230    *
 231    * @return a strut-like filler component.
 232    */
 233   public static Component createHorizontalStrut(int width)
 234   {
 235     Filler strut = new Filler(new Dimension(width, 0),
 236                               new Dimension(width, 0),
 237                               new Dimension(width, Integer.MAX_VALUE));
 238     return strut;
 239   }
 240
 241   public static Component createRigidArea(Dimension d)
 242   {
 243     return new Filler(d, d, d);
 244   }
 245
 246   public static Box createVerticalBox()
 247   {
 248     return new Box(BoxLayout.Y_AXIS);
 249   }
 250
 251   /**
 252    * Creates a filler component which acts as glue between components.
 253    * It does not take space unless some extra space is available. If extra
 254    * space is available, this component can expand in the Y direction.
 255    *
 256    * @return a glue-like filler component.
 257    */
 258   public static Component createVerticalGlue()
 259   {
 260     return createGlue();
 261   }
 262
 263   /**
 264    * Creates a filler component which acts as strut between components.
 265    * It will fill exactly the specified vertical size.
 266    *
 267    * @param height the height of this strut in pixels.
 268    *
 269    * @return a strut-like filler component.
 270    */
 271   public static Component createVerticalStrut(int height)
 272   {
 273     Filler strut = new Filler(new Dimension(0, height),
 274                               new Dimension(0, height),
 275                               new Dimension(Integer.MAX_VALUE, height));
 276     return strut;
 277   }
 278
 279   public void setLayout(LayoutManager l)
 280   {
 281     throw new AWTError("Not allowed to set layout managers for boxes.");
 282   }
 283
 284   public AccessibleContext getAccessibleContext()
 285   {
 286     if (accessibleContext == null)
 287       accessibleContext = new AccessibleBox();
 288     return accessibleContext;
 289   }
 290
 291
 292 }