/*
* @(#)DefaultButtonModel.java 1.45 04/05/05
*
* Copyright 2004 Sun Microsystems, Inc. All rights reserved.
* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*/
package javax.swing;
import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;
import java.io.Serializable;
import java.util.EventListener;
import javax.swing.event.*;
/**
* The default implementation of a Button
component's data model.
*
* Warning:
* Serialized objects of this class will not be compatible with
* future Swing releases. The current serialization support is
* appropriate for short term storage or RMI between applications running
* the same version of Swing. As of 1.4, support for long term storage
* of all JavaBeansTM
* has been added to the java.beans
package.
* Please see {@link java.beans.XMLEncoder}.
*
* @version 1.45 05/05/04
* @author Jeff Dinkins
*/
public class DefaultButtonModel implements ButtonModel, Serializable {
protected int stateMask = 0;
protected String actionCommand = null;
protected ButtonGroup group = null;
protected int mnemonic = 0;
/**
* Only one ChangeEvent
is needed per button model
* instance since the
* event's only state is the source property. The source of events
* generated is always "this".
*/
protected transient ChangeEvent changeEvent = null;
protected EventListenerList listenerList = new EventListenerList();
/**
* Constructs a default JButtonModel
.
*
*/
public DefaultButtonModel() {
stateMask = 0;
setEnabled(true);
}
/**
* Indicates partial commitment towards choosing the
* button.
*/
public final static int ARMED = 1 << 0;
/**
* Indicates that the button has been selected. Only needed for
* certain types of buttons - such as RadioButton or Checkbox.
*/
public final static int SELECTED = 1 << 1;
/**
* Indicates that the button has been "pressed"
* (typically, when the mouse is released).
*/
public final static int PRESSED = 1 << 2;
/**
* Indicates that the button can be selected by
* an input device (such as a mouse pointer).
*/
public final static int ENABLED = 1 << 3;
/**
* Indicates that the mouse is over the button.
*/
public final static int ROLLOVER = 1 << 4;
/**
* Sets the actionCommand
string that gets sent as
* part of the event when the button is pressed.
*
* @param actionCommand the String
that identifies
* the generated event
*/
public void setActionCommand(String actionCommand) {
this.actionCommand = actionCommand;
}
/**
* Returns the action command for this button.
*
* @return the String
that identifies the generated event
* @see #setActionCommand
*/
public String getActionCommand() {
return actionCommand;
}
/**
* Indicates partial commitment towards pressing the
* button.
*
* @return true if the button is armed, and ready to be pressed
* @see #setArmed
*/
public boolean isArmed() {
return (stateMask & ARMED) != 0;
}
/**
* Indicates if the button has been selected. Only needed for
* certain types of buttons - such as RadioButton or Checkbox.
*
* @return true if the button is selected
*/
public boolean isSelected() {
return (stateMask & SELECTED) != 0;
}
/**
* Indicates whether the button can be selected or pressed by
* an input device (such as a mouse pointer). (Checkbox-buttons
* are selected, regular buttons are "pressed".)
*
* @return true if the button is enabled, and therefore
* selectable (or pressable)
*/
public boolean isEnabled() {
return (stateMask & ENABLED) != 0;
}
/**
* Indicates whether button has been pressed.
*
* @return true if the button has been pressed
*/
public boolean isPressed() {
return (stateMask & PRESSED) != 0;
}
/**
* Indicates that the mouse is over the button.
*
* @return true if the mouse is over the button
*/
public boolean isRollover() {
return (stateMask & ROLLOVER) != 0;
}
/**
* Marks the button as "armed". If the mouse button is
* released while it is over this item, the button's action event
* fires. If the mouse button is released elsewhere, the
* event does not fire and the button is disarmed.
*
* @param b true to arm the button so it can be selected
*/
public void setArmed(boolean b) {
if((isArmed() == b) || !isEnabled()) {
return;
}
if (b) {
stateMask |= ARMED;
} else {
stateMask &= ~ARMED;
}
fireStateChanged();
}
/**
* Enables or disables the button.
*
* @param b true to enable the button
* @see #isEnabled
*/
public void setEnabled(boolean b) {
if(isEnabled() == b) {
return;
}
if (b) {
stateMask |= ENABLED;
} else {
stateMask &= ~ENABLED;
// unarm and unpress, just in case
stateMask &= ~ARMED;
stateMask &= ~PRESSED;
}
fireStateChanged();
}
/**
* Selects or deselects the button.
*
* @param b true selects the button,
* false deselects the button
*/
public void setSelected(boolean b) {
if (this.isSelected() == b) {
return;
}
if (b) {
stateMask |= SELECTED;
} else {
stateMask &= ~SELECTED;
}
fireItemStateChanged(
new ItemEvent(this,
ItemEvent.ITEM_STATE_CHANGED,
this,
b ? ItemEvent.SELECTED : ItemEvent.DESELECTED));
fireStateChanged();
}
/**
* Sets the button to pressed or unpressed.
*
* @param b true to set the button to "pressed"
* @see #isPressed
*/
public void setPressed(boolean b) {
if((isPressed() == b) || !isEnabled()) {
return;
}
if (b) {
stateMask |= PRESSED;
} else {
stateMask &= ~PRESSED;
}
if(!isPressed() && isArmed()) {
int modifiers = 0;
AWTEvent currentEvent = EventQueue.getCurrentEvent();
if (currentEvent instanceof InputEvent) {
modifiers = ((InputEvent)currentEvent).getModifiers();
} else if (currentEvent instanceof ActionEvent) {
modifiers = ((ActionEvent)currentEvent).getModifiers();
}
fireActionPerformed(
new ActionEvent(this, ActionEvent.ACTION_PERFORMED,
getActionCommand(),
EventQueue.getMostRecentEventTime(),
modifiers));
}
fireStateChanged();
}
/**
* Sets or clears the button's rollover state
*
* @param b true to turn on rollover
* @see #isRollover
*/
public void setRollover(boolean b) {
if((isRollover() == b) || !isEnabled()) {
return;
}
if (b) {
stateMask |= ROLLOVER;
} else {
stateMask &= ~ROLLOVER;
}
fireStateChanged();
}
/**
* Sets the keyboard mnemonic (shortcut key or
* accelerator key) for this button.
*
* @param key an int specifying the accelerator key
*/
public void setMnemonic(int key) {
mnemonic = key;
fireStateChanged();
}
/**
* Gets the keyboard mnemonic for this model
*
* @return an int specifying the accelerator key
* @see #setMnemonic
*/
public int getMnemonic() {
return mnemonic;
}
/**
* Adds a ChangeListener
to the button.
*
* @param l the listener to add
*/
public void addChangeListener(ChangeListener l) {
listenerList.add(ChangeListener.class, l);
}
/**
* Removes a ChangeListener
from the button.
*
* @param l the listener to remove
*/
public void removeChangeListener(ChangeListener l) {
listenerList.remove(ChangeListener.class, l);
}
/**
* Returns an array of all the change listeners
* registered on this DefaultButtonModel
.
*
* @return all of this model's ChangeListener
s
* or an empty
* array if no change listeners are currently registered
*
* @see #addChangeListener
* @see #removeChangeListener
*
* @since 1.4
*/
public ChangeListener[] getChangeListeners() {
return (ChangeListener[])listenerList.getListeners(
ChangeListener.class);
}
/**
* Notifies all listeners that have registered interest for
* notification on this event type. The event instance
* is created lazily.
*
* @see EventListenerList
*/
protected void fireStateChanged() {
// Guaranteed to return a non-null array
Object[] listeners = listenerList.getListenerList();
// Process the listeners last to first, notifying
// those that are interested in this event
for (int i = listeners.length-2; i>=0; i-=2) {
if (listeners[i]==ChangeListener.class) {
// Lazily create the event:
if (changeEvent == null)
changeEvent = new ChangeEvent(this);
((ChangeListener)listeners[i+1]).stateChanged(changeEvent);
}
}
}
/**
* Adds an ActionListener
to the button.
*
* @param l the listener to add
*/
public void addActionListener(ActionListener l) {
listenerList.add(ActionListener.class, l);
}
/**
* Removes an ActionListener
from the button.
*
* @param l the listener to remove
*/
public void removeActionListener(ActionListener l) {
listenerList.remove(ActionListener.class, l);
}
/**
* Returns an array of all the action listeners
* registered on this DefaultButtonModel
.
*
* @return all of this model's ActionListener
s
* or an empty
* array if no action listeners are currently registered
*
* @see #addActionListener
* @see #removeActionListener
*
* @since 1.4
*/
public ActionListener[] getActionListeners() {
return (ActionListener[])listenerList.getListeners(
ActionListener.class);
}
/**
* Notifies all listeners that have registered interest for
* notification on this event type.
*
* @param e the ActionEvent
to deliver to listeners
* @see EventListenerList
*/
protected void fireActionPerformed(ActionEvent e) {
// Guaranteed to return a non-null array
Object[] listeners = listenerList.getListenerList();
// Process the listeners last to first, notifying
// those that are interested in this event
for (int i = listeners.length-2; i>=0; i-=2) {
if (listeners[i]==ActionListener.class) {
// Lazily create the event:
// if (changeEvent == null)
// changeEvent = new ChangeEvent(this);
((ActionListener)listeners[i+1]).actionPerformed(e);
}
}
}
/**
* Adds an ItemListener
to the button.
*
* @param l the listener to add
*/
public void addItemListener(ItemListener l) {
listenerList.add(ItemListener.class, l);
}
/**
* Removes an ItemListener
from the button.
*
* @param l the listener to remove
*/
public void removeItemListener(ItemListener l) {
listenerList.remove(ItemListener.class, l);
}
/**
* Returns an array of all the item listeners
* registered on this DefaultButtonModel
.
*
* @return all of this model's ItemListener
s
* or an empty
* array if no item listeners are currently registered
*
* @see #addItemListener
* @see #removeItemListener
*
* @since 1.4
*/
public ItemListener[] getItemListeners() {
return (ItemListener[])listenerList.getListeners(ItemListener.class);
}
/**
* Notifies all listeners that have registered interest for
* notification on this event type.
*
* @param e the ItemEvent
to deliver to listeners
* @see EventListenerList
*/
protected void fireItemStateChanged(ItemEvent e) {
// Guaranteed to return a non-null array
Object[] listeners = listenerList.getListenerList();
// Process the listeners last to first, notifying
// those that are interested in this event
for (int i = listeners.length-2; i>=0; i-=2) {
if (listeners[i]==ItemListener.class) {
// Lazily create the event:
// if (changeEvent == null)
// changeEvent = new ChangeEvent(this);
((ItemListener)listeners[i+1]).itemStateChanged(e);
}
}
}
/**
* Returns an array of all the objects currently registered as
* FooListener
s
* upon this model.
* FooListener
s
* are registered using the addFooListener
method.
*
* You can specify the listenerType
argument
* with a class literal, such as FooListener.class
.
* For example, you can query a DefaultButtonModel
* instance m
* for its action listeners
* with the following code:
*
*
ActionListener[] als = (ActionListener[])(m.getListeners(ActionListener.class));* * If no such listeners exist, * this method returns an empty array. * * @param listenerType the type of listeners requested; * this parameter should specify an interface * that descends from
java.util.EventListener
* @return an array of all objects registered as
* FooListener
s
* on this model,
* or an empty array if no such
* listeners have been added
* @exception ClassCastException if listenerType
doesn't
* specify a class or interface that implements
* java.util.EventListener
*
* @see #getActionListeners
* @see #getChangeListeners
* @see #getItemListeners
*
* @since 1.3
*/
public null
. */
public Object[] getSelectedObjects() {
return null;
}
/**
* Identifies the group this button belongs to --
* needed for radio buttons, which are mutually
* exclusive within their group.
*
* @param group the ButtonGroup
this button belongs to
*/
public void setGroup(ButtonGroup group) {
this.group = group;
}
/**
* Returns the group that this button belongs to.
* Normally used with radio buttons, which are mutually
* exclusive within their group.
*
* @return a ButtonGroup
that this button belongs to
*
* @since 1.3
*/
public ButtonGroup getGroup() {
return group;
}
}