| /* CheckboxMenuItem.java -- A menu option with a checkbox on it. |
| Copyright (C) 1999, 2000, 2001, 2002, 2004, 2005 Free Software Foundation, Inc. |
| |
| This file is part of GNU Classpath. |
| |
| GNU Classpath is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2, or (at your option) |
| any later version. |
| |
| GNU Classpath is distributed in the hope that it will be useful, but |
| WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GNU Classpath; see the file COPYING. If not, write to the |
| Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
| 02110-1301 USA. |
| |
| Linking this library statically or dynamically with other modules is |
| making a combined work based on this library. Thus, the terms and |
| conditions of the GNU General Public License cover the whole |
| combination. |
| |
| As a special exception, the copyright holders of this library give you |
| permission to link this library with independent modules to produce an |
| executable, regardless of the license terms of these independent |
| modules, and to copy and distribute the resulting executable under |
| terms of your choice, provided that you also meet, for each linked |
| independent module, the terms and conditions of the license of that |
| module. An independent module is a module which is not derived from |
| or based on this library. If you modify this library, you may extend |
| this exception to your version of the library, but you are not |
| obligated to do so. If you do not wish to do so, delete this |
| exception statement from your version. */ |
| |
| |
| package java.awt; |
| |
| import java.awt.event.ItemEvent; |
| import java.awt.event.ItemListener; |
| import java.awt.peer.CheckboxMenuItemPeer; |
| import java.util.EventListener; |
| |
| import javax.accessibility.Accessible; |
| import javax.accessibility.AccessibleAction; |
| import javax.accessibility.AccessibleContext; |
| import javax.accessibility.AccessibleValue; |
| |
| /** |
| * This class implements a menu item that has a checkbox on it indicating |
| * the selected state of some option. |
| * |
| * @author Aaron M. Renn (arenn@urbanophile.com) |
| * @author Tom Tromey (tromey@redhat.com) |
| */ |
| public class CheckboxMenuItem extends MenuItem |
| implements ItemSelectable, Accessible |
| { |
| |
| /* |
| * Static Variables |
| */ |
| |
| /** |
| * The number used to generate the name returned by getName. |
| */ |
| private static transient long next_chkmenuitem_number; |
| |
| // Serialization constant |
| private static final long serialVersionUID = 6190621106981774043L; |
| |
| /* |
| * Instance Variables |
| */ |
| |
| /** |
| * @serial The state of the checkbox, with <code>true</code> being on and |
| * <code>false</code> being off. |
| */ |
| private boolean state; |
| |
| // List of registered ItemListeners |
| private transient ItemListener item_listeners; |
| |
| /*************************************************************************/ |
| |
| /* |
| * Constructors |
| */ |
| |
| /** |
| * Initializes a new instance of <code>CheckboxMenuItem</code> with no |
| * label and an initial state of off. |
| * |
| * @exception HeadlessException If GraphicsEnvironment.isHeadless() |
| * returns true. |
| */ |
| public |
| CheckboxMenuItem() |
| { |
| this("", false); |
| } |
| |
| /*************************************************************************/ |
| |
| /** |
| * Initializes a new instance of <code>CheckboxMenuItem</code> with the |
| * specified label and an initial state of off. |
| * |
| * @param label The label of the menu item. |
| * |
| * @exception HeadlessException If GraphicsEnvironment.isHeadless() |
| * returns true. |
| */ |
| public |
| CheckboxMenuItem(String label) |
| { |
| this(label, false); |
| } |
| |
| /*************************************************************************/ |
| |
| /** |
| * Initializes a new instance of <code>CheckboxMenuItem</code> with the |
| * specified label and initial state. |
| * |
| * @param label The label of the menu item. |
| * @param state The initial state of the menu item, where <code>true</code> |
| * is on, and <code>false</code> is off. |
| * |
| * @exception HeadlessException If GraphicsEnvironment.isHeadless() |
| * returns true. |
| */ |
| public |
| CheckboxMenuItem(String label, boolean state) |
| { |
| super(label); |
| this.state = state; |
| |
| if (GraphicsEnvironment.isHeadless()) |
| throw new HeadlessException (); |
| } |
| |
| /*************************************************************************/ |
| |
| /* |
| * Instance Methods |
| */ |
| |
| /** |
| * Returns the state of this menu item. |
| * |
| * @return The state of this menu item. |
| */ |
| public boolean |
| getState() |
| { |
| return(state); |
| } |
| |
| /*************************************************************************/ |
| |
| /** |
| * Sets the state of this menu item. |
| * |
| * @param state The initial state of the menu item, where <code>true</code> |
| * is on, and <code>false</code> is off. |
| */ |
| public synchronized void |
| setState(boolean state) |
| { |
| this.state = state; |
| if (peer != null) |
| { |
| CheckboxMenuItemPeer cp = (CheckboxMenuItemPeer) peer; |
| cp.setState (state); |
| } |
| } |
| |
| /*************************************************************************/ |
| |
| /** |
| * Returns an array of length 1 with the menu item label for this object |
| * if the state is on. Otherwise <code>null</code> is returned. |
| * |
| * @return An array with this menu item's label if it has a state of on, |
| * or <code>null</code> otherwise. |
| */ |
| public Object[] |
| getSelectedObjects() |
| { |
| if (state == false) |
| return(null); |
| |
| Object[] obj = new Object[1]; |
| obj[0] = getLabel(); |
| |
| return(obj); |
| } |
| |
| /*************************************************************************/ |
| |
| /** |
| * Create's this object's native peer |
| */ |
| public synchronized void |
| addNotify() |
| { |
| if (peer == null) |
| peer = getToolkit().createCheckboxMenuItem(this); |
| |
| super.addNotify (); |
| } |
| |
| /*************************************************************************/ |
| |
| /** |
| * Adds the specified listener to the list of registered item listeners |
| * for this object. |
| * |
| * @param listener The listener to add. |
| */ |
| public synchronized void |
| addItemListener(ItemListener listener) |
| { |
| item_listeners = AWTEventMulticaster.add(item_listeners, listener); |
| |
| enableEvents(AWTEvent.ITEM_EVENT_MASK); |
| } |
| |
| /*************************************************************************/ |
| |
| /** |
| * Removes the specified listener from the list of registered item |
| * listeners for this object. |
| * |
| * @param listener The listener to remove. |
| */ |
| public synchronized void |
| removeItemListener(ItemListener listener) |
| { |
| item_listeners = AWTEventMulticaster.remove(item_listeners, listener); |
| } |
| |
| /*************************************************************************/ |
| |
| /** |
| * Processes the specified event by calling <code>processItemEvent()</code> |
| * if it is an instance of <code>ItemEvent</code> or calling the superclass |
| * method otherwise. |
| * |
| * @param event The event to process. |
| */ |
| protected void |
| processEvent(AWTEvent event) |
| { |
| if (event instanceof ItemEvent) |
| processItemEvent((ItemEvent)event); |
| else |
| super.processEvent(event); |
| } |
| |
| /*************************************************************************/ |
| |
| /** |
| * Processes the specified event by dispatching it to any registered listeners. |
| * |
| * @param event The event to process. |
| */ |
| protected void |
| processItemEvent(ItemEvent event) |
| { |
| if (item_listeners != null) |
| item_listeners.itemStateChanged(event); |
| } |
| |
| void |
| dispatchEventImpl(AWTEvent e) |
| { |
| if (e instanceof ItemEvent) |
| { |
| synchronized (this) |
| { |
| state = (((ItemEvent) e).getStateChange() == ItemEvent.SELECTED); |
| } |
| } |
| |
| if (e.id <= ItemEvent.ITEM_LAST |
| && e.id >= ItemEvent.ITEM_FIRST |
| && (item_listeners != null |
| || (eventMask & AWTEvent.ITEM_EVENT_MASK) != 0)) |
| processEvent(e); |
| else |
| super.dispatchEventImpl(e); |
| } |
| |
| /*************************************************************************/ |
| |
| /** |
| * Returns a debugging string for this object. |
| * |
| * @return A debugging string for this object. |
| */ |
| public String |
| paramString() |
| { |
| return ("label=" + getLabel() + ",state=" + state |
| + "," + super.paramString()); |
| } |
| |
| /** |
| * Returns an array of all the objects currently registered as FooListeners |
| * upon this <code>CheckboxMenuItem</code>. FooListeners are registered using |
| * the addFooListener method. |
| * |
| * @exception ClassCastException If listenerType doesn't specify a class or |
| * interface that implements java.util.EventListener. |
| */ |
| public EventListener[] getListeners (Class listenerType) |
| { |
| if (listenerType == ItemListener.class) |
| return AWTEventMulticaster.getListeners (item_listeners, listenerType); |
| |
| return super.getListeners (listenerType); |
| } |
| |
| /** |
| * Returns an aray of all item listeners currently registered to this |
| * <code>CheckBoxMenuItem</code>. |
| */ |
| public ItemListener[] getItemListeners () |
| { |
| return (ItemListener[]) getListeners (ItemListener.class); |
| } |
| |
| |
| protected class AccessibleAWTCheckboxMenuItem extends AccessibleAWTMenuItem |
| implements AccessibleAction, AccessibleValue |
| { |
| // I think the base class provides the necessary implementation |
| |
| private static final long serialVersionUID = -1122642964303476L; |
| } |
| |
| /** |
| * Gets the AccessibleContext associated with this <code>CheckboxMenuItem</code>. |
| * The context is created, if necessary. |
| * |
| * @return the associated context |
| */ |
| public AccessibleContext getAccessibleContext() |
| { |
| /* Create the context if this is the first request */ |
| if (accessibleContext == null) |
| accessibleContext = new AccessibleAWTCheckboxMenuItem(); |
| return accessibleContext; |
| } |
| |
| /** |
| * Generate a unique name for this <code>CheckboxMenuItem</code>. |
| * |
| * @return A unique name for this <code>CheckboxMenuItem</code>. |
| */ |
| String generateName() |
| { |
| return "chkmenuitem" + getUniqueLong(); |
| } |
| |
| private static synchronized long getUniqueLong() |
| { |
| return next_chkmenuitem_number++; |
| } |
| |
| } // class CheckboxMenuItem |
| |