| /* Checkbox.java -- An AWT checkbox widget |
| Copyright (C) 1999, 2000, 2001, 2002 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., 59 Temple Place, Suite 330, Boston, MA |
| 02111-1307 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.peer.CheckboxPeer; |
| import java.awt.peer.ComponentPeer; |
| import java.awt.event.ItemEvent; |
| import java.awt.event.ItemListener; |
| import java.io.Serializable; |
| |
| /** |
| * This class implements a component which has an on/off state. Two |
| * or more Checkboxes can be grouped by a CheckboxGroup. |
| * |
| * @author Aaron M. Renn (arenn@urbanophile.com) |
| * @author Tom Tromey <tromey@redhat.com> |
| */ |
| public class Checkbox extends Component implements ItemSelectable, Serializable |
| { |
| |
| // FIXME: Need readObject/writeObject for this. |
| |
| /* |
| * Static Variables |
| */ |
| |
| // Serialization Constant |
| private static final long serialVersionUID = 7270714317450821763L; |
| |
| /*************************************************************************/ |
| |
| /* |
| * Instance Variables |
| */ |
| |
| /** |
| * @serial The checkbox group for this checkbox. |
| */ |
| private CheckboxGroup group; |
| |
| /** |
| * @serial The label on this checkbox. |
| */ |
| private String label; |
| |
| /** |
| * @serial The state of this checkbox. |
| */ |
| private boolean state; |
| |
| // The list of listeners for this object. |
| private transient ItemListener item_listeners; |
| |
| /*************************************************************************/ |
| |
| /* |
| * Constructors |
| */ |
| |
| /** |
| * Initializes a new instance of <code>Checkbox</code> with no label, |
| * an initial state of off, and that is not part of any checkbox group. |
| */ |
| public |
| Checkbox() |
| { |
| this("", false, null); |
| } |
| |
| /*************************************************************************/ |
| |
| /** |
| * Initializes a new instance of <code>Checkbox</code> with the specified |
| * label, an initial state of off, and that is not part of any checkbox |
| * group. |
| * |
| * @param label The label for this checkbox. |
| */ |
| public |
| Checkbox(String label) |
| { |
| this(label, false, null); |
| } |
| |
| /*************************************************************************/ |
| |
| /** |
| * Initializes a new instance of <code>Checkbox</code> with the specified |
| * label and initial state, and that is not part of any checkbox |
| * group. |
| * |
| * @param label The label for this checkbox. |
| * @param state The initial state of the checkbox, <code>true</code> for |
| * on, <code>false</code> for off. |
| */ |
| public |
| Checkbox(String label, boolean state) |
| { |
| this(label, state, null); |
| } |
| |
| /*************************************************************************/ |
| |
| /** |
| * Initializes a new instance of <code>Checkbox</code> with the specified |
| * label, initial state, and checkbox group. |
| * |
| * @param label The label for this checkbox. |
| * @param group The checkbox group for this box, or <code>null</code> |
| * if there is no checkbox group. |
| * @param state The initial state of the checkbox, <code>true</code> for |
| * on, <code>false</code> for off. |
| */ |
| public |
| Checkbox(String label, CheckboxGroup group, boolean state) |
| { |
| this(label, state, group); |
| } |
| |
| /*************************************************************************/ |
| |
| /** |
| * Initializes a new instance of <code>Checkbox</code> with the specified |
| * label, initial state, and checkbox group. |
| * |
| * @param label The label for this checkbox. |
| * @param state The initial state of the checkbox, <code>true</code> for |
| * on, <code>false</code> for off. |
| * @param group The checkbox group for this box, or <code>null</code> |
| * if there is no checkbox group. |
| */ |
| public |
| Checkbox(String label, boolean state, CheckboxGroup group) |
| { |
| this.label = label; |
| this.state = state; |
| this.group = group; |
| } |
| |
| /*************************************************************************/ |
| |
| /* |
| * Instance Variables |
| */ |
| |
| /** |
| * Returns the label for this checkbox. |
| * |
| * @return The label for this checkbox. |
| */ |
| public String |
| getLabel() |
| { |
| return(label); |
| } |
| |
| /*************************************************************************/ |
| |
| /** |
| * Sets the label for this checkbox to the specified value. |
| * |
| * @param label The new checkbox label. |
| */ |
| public synchronized void |
| setLabel(String label) |
| { |
| this.label = label; |
| if (peer != null) |
| { |
| CheckboxPeer cp = (CheckboxPeer) peer; |
| cp.setLabel(label); |
| } |
| } |
| |
| /*************************************************************************/ |
| |
| /** |
| * Returns the state of this checkbox. |
| * |
| * @return The state of this checkbox, which will be <code>true</code> for |
| * on and <code>false</code> for off. |
| */ |
| public boolean |
| getState() |
| { |
| return(state); |
| } |
| |
| /*************************************************************************/ |
| |
| /** |
| * Sets the state of this checkbox to the specified value. |
| * |
| * @param state The new state of the checkbox, which will be <code>true</code> |
| * for on or <code>false</code> for off. |
| */ |
| public synchronized void |
| setState(boolean state) |
| { |
| this.state = state; |
| if (peer != null) |
| { |
| CheckboxPeer cp = (CheckboxPeer) peer; |
| cp.setState (state); |
| } |
| } |
| |
| /*************************************************************************/ |
| |
| /** |
| * Returns an array of length one containing the checkbox label if this |
| * checkbox is selected. Otherwise <code>null</code> is returned. |
| * |
| * @return The selection state of this checkbox. |
| */ |
| public Object[] |
| getSelectedObjects() |
| { |
| if (state == false) |
| return(null); |
| |
| Object[] objs = new Object[1]; |
| objs[0] = label; |
| |
| return(objs); |
| } |
| |
| /*************************************************************************/ |
| |
| /** |
| * Returns the checkbox group this object is a member of, if any. |
| * |
| * @return This object's checkbox group, of <code>null</code> if it is |
| * not a member of any group. |
| */ |
| public CheckboxGroup |
| getCheckboxGroup() |
| { |
| return(group); |
| } |
| |
| /*************************************************************************/ |
| |
| /** |
| * Sets this object's checkbox group to the specified group. |
| * |
| * @param group The new checkbox group, or <code>null</code> to make this |
| * object part of no checkbox group. |
| */ |
| public synchronized void |
| setCheckboxGroup(CheckboxGroup group) |
| { |
| this.group = group; |
| if (peer != null) |
| { |
| CheckboxPeer cp = (CheckboxPeer) peer; |
| cp.setCheckboxGroup (group); |
| } |
| } |
| |
| /*************************************************************************/ |
| |
| /** |
| * Creates this object's native peer. |
| */ |
| public void |
| addNotify() |
| { |
| if (peer == null) |
| peer = getToolkit ().createCheckbox (this); |
| super.addNotify (); |
| } |
| |
| /*************************************************************************/ |
| |
| /** |
| * Adds a new listeners to the list of registered listeners for this object. |
| * |
| * @param listener The new listener to add. |
| */ |
| public synchronized void |
| addItemListener(ItemListener listener) |
| { |
| item_listeners = AWTEventMulticaster.add(item_listeners, listener); |
| } |
| |
| /*************************************************************************/ |
| |
| /** |
| * Removes a listener from the list of registered listeners for this object. |
| * |
| * @param listener The listener to remove. |
| */ |
| public synchronized void |
| removeItemListener(ItemListener listener) |
| { |
| item_listeners = AWTEventMulticaster.remove(item_listeners, listener); |
| } |
| |
| /*************************************************************************/ |
| |
| /** |
| * Processes this event by calling <code>processItemEvent()</code> if it |
| * is any instance of <code>ItemEvent</code>. Otherwise it is passed to |
| * the superclass for processing. |
| * |
| * @param event The event to process. |
| */ |
| protected void |
| processEvent(AWTEvent event) |
| { |
| if (event instanceof ItemEvent) |
| processItemEvent((ItemEvent)event); |
| else |
| super.processEvent(event); |
| } |
| |
| /*************************************************************************/ |
| |
| /** |
| * Processes this event by dispatching it to any registered listeners. |
| * |
| * @param event The <code>ItemEvent</code> to process. |
| */ |
| protected void |
| processItemEvent(ItemEvent event) |
| { |
| if (item_listeners != null) |
| item_listeners.itemStateChanged(event); |
| } |
| |
| /*************************************************************************/ |
| |
| /** |
| * Returns a debugging string for this object. |
| */ |
| protected String |
| paramString() |
| { |
| return ("label=" + label + ",state=" + state + ",group=" + group |
| + "," + super.paramString()); |
| } |
| |
| } // class Checkbox |