| /* Checkbox.java -- An AWT checkbox widget |
| Copyright (C) 1999, 2000, 2001, 2002, 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., 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.event.ItemEvent; |
| import java.awt.event.ItemListener; |
| import java.awt.peer.CheckboxPeer; |
| import java.io.Serializable; |
| |
| import javax.accessibility.Accessible; |
| import javax.accessibility.AccessibleAction; |
| import javax.accessibility.AccessibleContext; |
| import javax.accessibility.AccessibleRole; |
| import javax.accessibility.AccessibleState; |
| import javax.accessibility.AccessibleStateSet; |
| import javax.accessibility.AccessibleValue; |
| |
| /** |
| * 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, Accessible, 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; |
| |
| /* |
| * The number used to generate the name returned by getName. |
| */ |
| private static transient long next_checkbox_number; |
| |
| /** |
| * This class provides accessibility support for the |
| * checkbox. |
| * |
| * @author Jerry Quinn (jlquinn@optonline.net) |
| * @author Andrew John Hughes (gnu_andrew@member.fsf.org) |
| */ |
| protected class AccessibleAWTCheckbox |
| extends AccessibleAWTComponent |
| implements ItemListener, AccessibleAction, AccessibleValue |
| { |
| /** |
| * Serialization constant to match JDK 1.5 |
| */ |
| private static final long serialVersionUID = 7881579233144754107L; |
| |
| /** |
| * Default constructor which simply calls the |
| * super class for generic component accessibility |
| * handling. |
| */ |
| public AccessibleAWTCheckbox() |
| { |
| super(); |
| } |
| |
| /** |
| * Captures changes to the state of the checkbox and |
| * fires appropriate accessible property change events. |
| * |
| * @param event the event fired. |
| * @see java.awt.event.ItemListener#itemStateChanged(java.awt.event.ItemEvent) |
| */ |
| public void itemStateChanged(ItemEvent event) |
| { |
| firePropertyChange(ACCESSIBLE_STATE_PROPERTY, |
| state ? null : AccessibleState.CHECKED, |
| state ? AccessibleState.CHECKED : null); |
| } |
| |
| /** |
| * Returns an implementation of the <code>AccessibleAction</code> |
| * interface for this accessible object. In this case, the |
| * current instance is simply returned (with a more appropriate |
| * type), as it also implements the accessible action as well as |
| * the context. |
| * |
| * @return the accessible action associated with this context. |
| * @see javax.accessibility.AccessibleAction |
| */ |
| public AccessibleAction getAccessibleAction() |
| { |
| return this; |
| } |
| |
| /** |
| * Returns an implementation of the <code>AccessibleValue</code> |
| * interface for this accessible object. In this case, the |
| * current instance is simply returned (with a more appropriate |
| * type), as it also implements the accessible value as well as |
| * the context. |
| * |
| * @return the accessible value associated with this context. |
| * @see javax.accessibility.AccessibleValue |
| */ |
| public AccessibleValue getAccessibleValue() |
| { |
| return this; |
| } |
| |
| /* |
| * The following methods are implemented in the JDK (up to |
| * 1.5) as stubs. We do likewise here. |
| */ |
| |
| /** |
| * Returns the number of actions associated with this accessible |
| * object. This default implementation returns 0. |
| * |
| * @return the number of accessible actions available. |
| * @see javax.accessibility.AccessibleAction#getAccessibleActionCount() |
| */ |
| public int getAccessibleActionCount() |
| { |
| // 1.4.1 and 1.5 do this |
| return 0; |
| } |
| |
| /** |
| * Returns a description of the action with the supplied id. |
| * This default implementation always returns null. |
| * |
| * @param i the id of the action whose description should be |
| * retrieved. |
| * @return a <code>String</code> describing the action. |
| * @see javax.accessibility.AccessibleAction#getAccessibleActionDescription(int) |
| */ |
| public String getAccessibleActionDescription(int i) |
| { |
| // 1.5 does this |
| return null; |
| } |
| |
| /** |
| * Executes the action with the specified id. This |
| * default implementation simply returns false. |
| * |
| * @param i the id of the action to perform. |
| * @return true if the action was performed. |
| * @see javax.accessibility.AccessibleAction#doAccessibleAction(int) |
| */ |
| public boolean doAccessibleAction(int i) |
| { |
| // 1.5 does this |
| return false; |
| } |
| |
| /** |
| * Returns the current value of this accessible object. |
| * If no value has been set, null is returned. This |
| * default implementation always returns null, regardless. |
| * |
| * @return the numeric value of this object, or null if |
| * no value has been set. |
| * @see javax.accessibility.AccessibleValue#getCurrentAccessibleValue() |
| */ |
| public Number getCurrentAccessibleValue() |
| { |
| // 1.5 does this |
| return null; |
| } |
| |
| /** |
| * Sets the current value of this accessible object |
| * to that supplied. In this default implementation, |
| * the value is never set and the method always returns |
| * false. |
| * |
| * @param number the new accessible value. |
| * @return true if the value was set. |
| * @see javax.accessibility.AccessibleValue#setCurrentAccessibleValue(java.lang.Number) |
| */ |
| public boolean setCurrentAccessibleValue(Number number) |
| { |
| // 1.5 does this |
| return false; |
| } |
| |
| /** |
| * Returns the minimum acceptable accessible value used |
| * by this object, or null if no minimum value exists. |
| * This default implementation always returns null. |
| * |
| * @return the minimum acceptable accessible value, or null |
| * if there is no minimum. |
| * @see javax.accessibility.AccessibleValue#getMinimumAccessibleValue() |
| */ |
| public Number getMinimumAccessibleValue() |
| { |
| return null; |
| } |
| |
| /** |
| * Returns the maximum acceptable accessible value used |
| * by this object, or null if no maximum value exists. |
| * This default implementation always returns null. |
| * |
| * @return the maximum acceptable accessible value, or null |
| * if there is no maximum. |
| * @see javax.accessibility.AccessibleValue#getMaximumAccessibleValue() |
| */ |
| public Number getMaximumAccessibleValue() |
| { |
| return null; |
| } |
| |
| /** |
| * Returns the role of this accessible object. |
| * |
| * @return the instance of <code>AccessibleRole</code>, |
| * which describes this object. |
| * @see javax.accessibility.AccessibleRole |
| */ |
| public AccessibleRole getAccessibleRole() |
| { |
| return AccessibleRole.CHECK_BOX; |
| } |
| |
| /** |
| * Returns the state set of this accessible object. |
| * |
| * @return a set of <code>AccessibleState</code>s |
| * which represent the current state of the |
| * accessible object. |
| * @see javax.accessibility.AccessibleState |
| * @see javax.accessibility.AccessibleStateSet |
| */ |
| public AccessibleStateSet getAccessibleStateSet() |
| { |
| AccessibleStateSet set = super.getAccessibleStateSet(); |
| if (state) |
| set.add(AccessibleState.CHECKED); |
| return set; |
| } |
| |
| } |
| |
| /*************************************************************************/ |
| |
| /* |
| * 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 (); |
| } |
| |
| public ItemListener[] getItemListeners () |
| { |
| return (ItemListener[]) |
| AWTEventMulticaster.getListeners (item_listeners, ItemListener.class); |
| } |
| |
| /** |
| * 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); |
| } |
| |
| void |
| dispatchEventImpl(AWTEvent e) |
| { |
| 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. |
| */ |
| protected String |
| paramString() |
| { |
| return ("label=" + label + ",state=" + state + ",group=" + group |
| + "," + super.paramString()); |
| } |
| |
| /** |
| * Gets the AccessibleContext associated with this <code>Checkbox</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) |
| { |
| AccessibleAWTCheckbox ac = new AccessibleAWTCheckbox(); |
| accessibleContext = ac; |
| addItemListener(ac); |
| } |
| return accessibleContext; |
| } |
| |
| /** |
| * Generate a unique name for this checkbox. |
| * |
| * @return A unique name for this checkbox. |
| */ |
| String generateName() |
| { |
| return "checkbox" + getUniqueLong(); |
| } |
| |
| private static synchronized long getUniqueLong() |
| { |
| return next_checkbox_number++; |
| } |
| } |