/*
* @(#)JRadioButton.java 1.74 03/12/19
*
* 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.beans.*;
import javax.swing.plaf.*;
import javax.accessibility.*;
import java.io.ObjectOutputStream;
import java.io.ObjectInputStream;
import java.io.IOException;
/**
* An implementation of a radio button -- an item that can be selected or
* deselected, and which displays its state to the user.
* Used with a {@link ButtonGroup} object to create a group of buttons
* in which only one button at a time can be selected. (Create a ButtonGroup
* object and use its add
method to include the JRadioButton objects
* in the group.)
*
* Note: * The ButtonGroup object is a logical grouping -- not a physical grouping. * Tocreate a button panel, you should still create a {@link JPanel} or similar * container-object and add a {@link javax.swing.border.Border} to it to set it off from surrounding * components. **
* See How to Use Buttons, Check Boxes, and Radio Buttons * in The Java Tutorial * for further documentation. *
* 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}.
*
* @beaninfo
* attribute: isContainer false
* description: A component which can display it's state as selected or deselected.
*
* @see ButtonGroup
* @see JCheckBox
* @version 1.74 12/19/03
* @author Jeff Dinkins
*/
public class JRadioButton extends JToggleButton implements Accessible {
/**
* @see #getUIClassID
* @see #readObject
*/
private static final String uiClassID = "RadioButtonUI";
/**
* Creates an initially unselected radio button
* with no set text.
*/
public JRadioButton () {
this(null, null, false);
}
/**
* Creates an initially unselected radio button
* with the specified image but no text.
*
* @param icon the image that the button should display
*/
public JRadioButton(Icon icon) {
this(null, icon, false);
}
/**
* Creates a radiobutton where properties are taken from the
* Action supplied.
*
* @since 1.3
*/
public JRadioButton(Action a) {
this();
setAction(a);
}
/**
* Creates a radio button with the specified image
* and selection state, but no text.
*
* @param icon the image that the button should display
* @param selected if true, the button is initially selected;
* otherwise, the button is initially unselected
*/
public JRadioButton(Icon icon, boolean selected) {
this(null, icon, selected);
}
/**
* Creates an unselected radio button with the specified text.
*
* @param text the string displayed on the radio button
*/
public JRadioButton (String text) {
this(text, null, false);
}
/**
* Creates a radio button with the specified text
* and selection state.
*
* @param text the string displayed on the radio button
* @param selected if true, the button is initially selected;
* otherwise, the button is initially unselected
*/
public JRadioButton (String text, boolean selected) {
this(text, null, selected);
}
/**
* Creates a radio button that has the specified text and image,
* and that is initially unselected.
*
* @param text the string displayed on the radio button
* @param icon the image that the button should display
*/
public JRadioButton(String text, Icon icon) {
this(text, icon, false);
}
/**
* Creates a radio button that has the specified text, image,
* and selection state.
*
* @param text the string displayed on the radio button
* @param icon the image that the button should display
*/
public JRadioButton (String text, Icon icon, boolean selected) {
super(text, icon, selected);
setBorderPainted(false);
setHorizontalAlignment(LEADING);
}
/**
* Resets the UI property to a value from the current look and feel.
*
* @see JComponent#updateUI
*/
public void updateUI() {
setUI((ButtonUI)UIManager.getUI(this));
}
/**
* Returns the name of the L&F class
* that renders this component.
*
* @return String "RadioButtonUI"
* @see JComponent#getUIClassID
* @see UIDefaults#getUI
* @beaninfo
* expert: true
* description: A string that specifies the name of the L&F class.
*/
public String getUIClassID() {
return uiClassID;
}
/**
* Factory method which sets the ActionEvent
source's
* properties according to values from the Action instance. The
* properties which are set may differ for subclasses.
* By default, the properties which get set are Text, Mnemonic,
* Enabled, ActionCommand
, and ToolTipText
.
*
* @param a the Action from which to get the properties, or null
* @since 1.3
* @see Action
* @see #setAction
*/
protected void configurePropertiesFromAction(Action a) {
String[] types = { Action.MNEMONIC_KEY, Action.NAME,
Action.SHORT_DESCRIPTION,
Action.ACTION_COMMAND_KEY, "enabled" };
configurePropertiesFromAction(a, types);
}
/**
* Factory method which creates the PropertyChangeListener
* used to update the ActionEvent source as properties change on
* its Action instance. Subclasses may override this in order
* to provide their own PropertyChangeListener if the set of
* properties which should be kept up to date differs from the
* default properties (Text, Icon, Enabled, ToolTipText).
*
* Note that PropertyChangeListeners should avoid holding
* strong references to the ActionEvent source, as this may hinder
* garbage collection of the ActionEvent source and all components
* in its containment hierarchy.
*
* @since 1.3
* @see Action
* @see #setAction
*/
protected PropertyChangeListener createActionPropertyChangeListener(Action a) {
return new AbstractActionPropertyChangeListener(this, a) {
public void propertyChange(PropertyChangeEvent e) {
String propertyName = e.getPropertyName();
AbstractButton button = (AbstractButton)getTarget();
if (button == null) { //WeakRef GC'ed in 1.2
Action action = (Action)e.getSource();
action.removePropertyChangeListener(this);
} else {
if (propertyName.equals(Action.NAME)) {
String text = (String) e.getNewValue();
button.setText(text);
button.repaint();
} else if (propertyName.equals(Action.SHORT_DESCRIPTION)) {
String text = (String) e.getNewValue();
button.setToolTipText(text);
} else if (propertyName.equals("enabled")) {
Boolean enabledState = (Boolean) e.getNewValue();
button.setEnabled(enabledState.booleanValue());
button.repaint();
} else if (propertyName.equals(Action.ACTION_COMMAND_KEY)) {
button.setActionCommand((String)e.getNewValue());
}
}
}
};
}
/**
* See readObject() and writeObject() in JComponent for more
* information about serialization in Swing.
*/
private void writeObject(ObjectOutputStream s) throws IOException {
s.defaultWriteObject();
if (getUIClassID().equals(uiClassID)) {
byte count = JComponent.getWriteObjCounter(this);
JComponent.setWriteObjCounter(this, --count);
if (count == 0 && ui != null) {
ui.installUI(this);
}
}
}
/**
* Returns a string representation of this JRadioButton. This method
* is intended to be used only for debugging purposes, and the
* content and format of the returned string may vary between
* implementations. The returned string may be empty but may not
* be null
.
*
* @return a string representation of this JRadioButton.
*/
protected String paramString() {
return super.paramString();
}
/////////////////
// Accessibility support
////////////////
/**
* Gets the AccessibleContext associated with this JRadioButton.
* For JRadioButtons, the AccessibleContext takes the form of an
* AccessibleJRadioButton.
* A new AccessibleJRadioButton instance is created if necessary.
*
* @return an AccessibleJRadioButton that serves as the
* AccessibleContext of this JRadioButton
* @beaninfo
* expert: true
* description: The AccessibleContext associated with this Button
*/
public AccessibleContext getAccessibleContext() {
if (accessibleContext == null) {
accessibleContext = new AccessibleJRadioButton();
}
return accessibleContext;
}
/**
* This class implements accessibility support for the
* JRadioButton
class. It provides an implementation of the
* Java Accessibility API appropriate to radio button
* user-interface elements.
*
* 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}.
*/
protected class AccessibleJRadioButton extends AccessibleJToggleButton {
/**
* Get the role of this object.
*
* @return an instance of AccessibleRole describing the role of the object
* @see AccessibleRole
*/
public AccessibleRole getAccessibleRole() {
return AccessibleRole.RADIO_BUTTON;
}
} // inner class AccessibleJRadioButton
}