/*
* $Id: JXRadioGroup.java 3471 2009-08-27 13:10:39Z kleopatra $
*
* Copyright 2006 Sun Microsystems, Inc., 4150 Network Circle,
* Santa Clara, California 95054, U.S.A. All rights reserved.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
package org.hdesktop.swingx;
import java.awt.Component;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.List;
import javax.swing.AbstractButton;
import javax.swing.BoxLayout;
import javax.swing.ButtonGroup;
import javax.swing.ButtonModel;
import javax.swing.ComboBoxModel;
import javax.swing.JComboBox;
import javax.swing.JComponent;
import javax.swing.JPanel;
import javax.swing.JRadioButton;
import javax.swing.event.EventListenerList;
/**
* <p>
* {@code JXRadioGroup} is a group of radio buttons that functions as a unit. It
* is similar in concept to a {@link JComboBox} in functionality, but can offer
* a better presentation for a small number of choices. {@code JXRadioGroup}
* should be used in preference to {@code JComboBox} when the number of choices
* is small (less than six) or the choices are verbose.
* </p>
* <p>
* Notes:
* <ol>
* <li>Enabling and disabling the JXRadioGroup will enable/disable all of the
* child buttons inside the JXRadioGroup.</li>
* <li>
* If the generic type parameter of JXRadioGroup is a subclass of
* {@link AbstractButton}, then the buttons will be added "as is" to the
* container. If the generic type is anything else, buttons will be created as
* {@link JRadioButton} objects, and the button text will be set by calling
* toString() on the value object.</li>
* <li>
* Alternatively, if you want to configure the buttons individually, construct
* the JXRadioGroup normally, and then call {@link #getChildButton(int)} or
* {@link #getChildButton(Object)} and configure the buttons.</li>
* </ol>
* </p>
* <p>
* TODO back with a model (possibly reuse of extend {@link ComboBoxModel}
* </p>
*
* @author Amy Fowler
* @author Noel Grandin
* @version 1.0
*/
public class JXRadioGroup<T> extends JPanel {
private static final long serialVersionUID = 3257285842266567986L;
private ButtonGroup buttonGroup;
private final List<T> values = new ArrayList<T>();
private ActionSelectionListener actionHandler;
private List<ActionListener> actionListeners;
/**
* Create a default JXRadioGroup with a default layout axis of {@link BoxLayout#X_AXIS}.
*/
public JXRadioGroup() {
setLayout(new BoxLayout(this, BoxLayout.X_AXIS));
buttonGroup = new ButtonGroup();
}
/**
* Create a default JXRadioGroup with a default layout axis of {@link BoxLayout#X_AXIS}.
*
* @param radioValues the list of values used to create the group.
*/
public JXRadioGroup(T[] radioValues) {
this();
for (int i = 0; i < radioValues.length; i++) {
add(radioValues[i]);
}
}
/**
* Convenience factory method.
* Reduces code clutter when dealing with generics.
*
* @param radioValues the list of values used to create the group.
*/
public static <T> JXRadioGroup<T> create(T[] radioValues)
{
return new JXRadioGroup<T>(radioValues);
}
/**
* Set the layout axis of the radio group.
*
* @param axis values from {@link BoxLayout}.
*/
public void setLayoutAxis(int axis)
{
setLayout(new BoxLayout(this, axis));
}
/**
* Sets the values backing this group. This replaces the current set of
* values with the new set.
*
* @param radioValues
* the new backing values for this group
*/
public void setValues(T[] radioValues) {
clearAll();
for (int i = 0; i < radioValues.length; i++) {
add(radioValues[i]);
}
}
private void clearAll() {
values.clear();
buttonGroup = new ButtonGroup();
// remove all the child components
removeAll();
}
/**
* You can use this method to manually add your own AbstractButton objects, provided you declared
* the class as <code>JXRadioGroup<JRadioButton></code>.
*/
public void add(T radioValue) {
if (values.contains(radioValue))
{
throw new IllegalArgumentException("cannot add the same value twice " + radioValue);
}
if (radioValue instanceof AbstractButton) {
values.add(radioValue);
addButton((AbstractButton) radioValue);
} else {
values.add(radioValue);
// Note: the "quote + object" trick here allows null values
addButton(new JRadioButton(""+radioValue));
}
}
private void addButton(AbstractButton button) {
buttonGroup.add(button);
super.add(button);
if (actionHandler == null) {
actionHandler = new ActionSelectionListener();
}
button.addActionListener(actionHandler);
button.addItemListener(actionHandler);
}
private class ActionSelectionListener implements ActionListener, ItemListener
{
public void actionPerformed(ActionEvent e) {
fireActionEvent(e);
}
public void itemStateChanged(ItemEvent e) {
fireActionEvent(null);
}
}
/**
* Gets the currently selected button.
*
* @return the currently selected button
* @see #getSelectedValue()
*/
public AbstractButton getSelectedButton() {
final ButtonModel selectedModel = buttonGroup.getSelection();
final AbstractButton children[] = getButtonComponents();
for (int i = 0; i < children.length; i++) {
AbstractButton button = children[i];
if (button.getModel() == selectedModel) {
return button;
}
}
return null;
}
private AbstractButton[] getButtonComponents() {
final Component[] children = getComponents();
final List<AbstractButton> buttons = new ArrayList<AbstractButton>();
for (int i = 0; i < children.length; i++) {
if (children[i] instanceof AbstractButton) {
buttons.add((AbstractButton) children[i]);
}
}
return buttons.toArray(new AbstractButton[buttons.size()]);
}
private int getSelectedIndex() {
final ButtonModel selectedModel = buttonGroup.getSelection();
final Component children[] = getButtonComponents();
for (int i = 0; i < children.length; i++) {
AbstractButton button = (AbstractButton) children[i];
if (button.getModel() == selectedModel) {
return i;
}
}
return -1;
}
/**
* The currently selected value.
*
* @return the current value
*/
public T getSelectedValue() {
final int index = getSelectedIndex();
return (index < 0 || index >= values.size()) ? null : values.get(index);
}
/**
* Selects the supplied value.
*
* @param value
* the value to select
*/
public void setSelectedValue(T value) {
final int index = values.indexOf(value);
AbstractButton button = getButtonComponents()[index];
button.setSelected(true);
}
/**
* Retrieve the child button by index.
*/
public AbstractButton getChildButton(int index) {
return getButtonComponents()[index];
}
/**
* Retrieve the child button that represents this value.
*/
public AbstractButton getChildButton(T value) {
final int index = values.indexOf(value);
return getButtonComponents()[index];
}
/**
* Get the number of child buttons.
*/
public int getChildButtonCount() {
return getButtonComponents().length;
}
/**
* Adds an <code>ActionListener</code>.
* <p>
* The <code>ActionListener</code> will receive an <code>ActionEvent</code>
* when a selection has been made.
*
* @param l the <code>ActionListener</code> that is to be notified
* @see #setSelectedItem
*/
public void addActionListener(ActionListener l) {
if (actionListeners == null) {
actionListeners = new ArrayList<ActionListener>();
}
actionListeners.add(l);
}
/**
* Removes an <code>ActionListener</code>.
*
* @param l
* the <code>ActionListener</code> to remove
*/
public void removeActionListener(ActionListener l) {
if (actionListeners != null) {
actionListeners.remove(l);
}
}
/**
* Returns an array of all the <code>ActionListener</code>s added
* to this JRadioGroup with addActionListener().
*
* @return all of the <code>ActionListener</code>s added or an empty
* array if no listeners have been added
*/
public ActionListener[] getActionListeners() {
if (actionListeners != null) {
return actionListeners.toArray(new ActionListener[0]);
}
return new ActionListener[0];
}
/**
* Notifies all listeners that have registered interest for notification on
* this event type.
*
* @param e
* the event to pass to the listeners
* @see EventListenerList
*/
protected void fireActionEvent(ActionEvent e) {
if (actionListeners != null) {
for (int i = 0; i < actionListeners.size(); i++) {
ActionListener l = actionListeners.get(i);
l.actionPerformed(e);
}
}
}
/**
* Enable/disable all of the child buttons
*
* @see JComponent#setEnabled(boolean)
*/
@Override
public void setEnabled(boolean enabled) {
super.setEnabled(enabled);
for (Enumeration<AbstractButton> en = buttonGroup.getElements(); en.hasMoreElements();) {
final AbstractButton button = en.nextElement();
/* We don't want to enable a button where the action does not
* permit it. */
if (enabled && button.getAction() != null
&& !button.getAction().isEnabled()) {
// do nothing
} else {
button.setEnabled(enabled);
}
}
}
}