Source for javax.swing.JButton

   1: /* JButton.java --
   2:    Copyright (C) 2002, 2004, 2005 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: package javax.swing;
  39: 
  40: import javax.accessibility.Accessible;
  41: import javax.accessibility.AccessibleContext;
  42: import javax.accessibility.AccessibleRole;
  43: import javax.swing.plaf.ButtonUI;
  44: 
  45: 
  46: /**
  47:  * A general purpose push button. <code>JButton</code>s can display a label,
  48:  * an {@link Icon} or both.
  49:  *
  50:  * @author Ronald Veldema (rveldema@cs.vu.nl)
  51:  */
  52: public class JButton extends AbstractButton
  53:   implements Accessible
  54: {
  55: 
  56:   /**
  57:    * Accessibility support for JButtons.
  58:    */
  59:   protected class AccessibleJButton
  60:     extends AbstractButton.AccessibleAbstractButton
  61:   {
  62:     /**
  63:      * Returns the accessible role that this component represents.
  64:      * This is {@link AccessibleRole#PUSH_BUTTON} for <code>JButton</code>s.
  65:      *
  66:      * @return the accessible role that this component represents
  67:      */
  68:     public AccessibleRole getAccessibleRole()
  69:     {
  70:       return AccessibleRole.PUSH_BUTTON;
  71:     }
  72:   }
  73: 
  74:   private static final long serialVersionUID = -1907255238954382202L;
  75:   boolean def;
  76:   boolean is_def;
  77: 
  78:   public JButton()
  79:   {
  80:     this(null, null);
  81:   }
  82: 
  83:   public JButton(Action a)
  84:   {
  85:     this();
  86:     setAction(a);
  87:   }
  88: 
  89:   public JButton(Icon icon)
  90:   {
  91:     this(null, icon);
  92:   }
  93: 
  94:   public JButton(String text)
  95:   {
  96:     this(text, null);
  97:   }
  98: 
  99:   public JButton(String text, Icon icon)
 100:   {
 101:     super();
 102:     init(text, icon);
 103:     setModel(new DefaultButtonModel());
 104:   }
 105: 
 106:   public Object[] getSelectedObjects()
 107:   {
 108:     return null;
 109:   }
 110: 
 111:   protected void configurePropertiesFromAction(Action a)
 112:   {
 113:     // Factory method which sets the AbstractButton's properties according to
 114:     // values from the Action instance. 
 115:     super.configurePropertiesFromAction(a);
 116:   }
 117: 
 118:   public AccessibleContext getAccessibleContext()
 119:   {
 120:     if (accessibleContext == null)
 121:       accessibleContext = new AccessibleJButton();
 122:     return accessibleContext;
 123:   }
 124: 
 125:   public String getUIClassID()
 126:   {
 127:     // Returns a string that specifies the name of the L&F class that renders
 128:     // this component.  
 129:     return "ButtonUI";
 130:   }
 131: 
 132:   public boolean isDefaultButton()
 133:   {
 134:     // Returns whether or not this button is the default button on the
 135:     // RootPane.
 136:     return is_def;
 137:   }
 138: 
 139:   public boolean isDefaultCapable()
 140:   {
 141:     // Returns whether or not this button is capable of being the default
 142:     // button on the RootPane. 
 143:     return def;
 144:   }
 145: 
 146:   protected String paramString()
 147:   {
 148:     String superParam = super.paramString();
 149: 
 150:     // 41 is the maximum number of chars which may be needed.
 151:     StringBuffer sb = new StringBuffer(41);
 152:     sb.append(",defaultButton=").append(is_def);
 153:     sb.append(",defaultCapable=").append(def);
 154: 
 155:     return superParam + sb.toString();
 156:   }
 157: 
 158:   /**
 159:    * Overrides JComponent.removeNotify to check if this button is currently
 160:    * set as the default button on the RootPane, and if so, sets the RootPane's
 161:    * default button to null to ensure the RootPane doesn't hold onto an invalid
 162:    * button reference.
 163:    */
 164:   public void removeNotify()
 165:   {
 166:     JRootPane root = SwingUtilities.getRootPane(this);
 167:     if (root != null && root.getDefaultButton() == this)
 168:       root.setDefaultButton(null);
 169:     super.removeNotify();
 170:   }
 171: 
 172:   public void setDefaultCapable(boolean defaultCapable)
 173:   {
 174:     def = defaultCapable;
 175:   }
 176: 
 177:   public void updateUI()
 178:   {
 179:     setUI((ButtonUI) UIManager.getUI(this));
 180:   }
 181: }