/* * Copyright (c) 1997, 2006, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code 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 * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ 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. * To create 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. *
*

* Buttons can be configured, and to some degree controlled, by * Actions. Using an * Action with a button has many benefits beyond directly * configuring a button. Refer to * Swing Components Supporting Action for more * details, and you can find more information in How * to Use Actions, a section in The Java Tutorial. *

* See How to Use Buttons, Check Boxes, and Radio Buttons * in The Java Tutorial * for further documentation. *

* Warning: Swing is not thread safe. For more * information see Swing's Threading * Policy. *

* 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 * @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; } /** * The icon for radio buttons comes from the look and feel, * not the Action. */ void setIconFromAction(Action a) { } /** * 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 }