| /* |
| * Copyright (c) 1997, 2015, 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.event.*; |
| import java.util.Vector; |
| import java.util.Enumeration; |
| import java.io.Serializable; |
| |
| /** |
| * This class is used to create a multiple-exclusion scope for |
| * a set of buttons. Creating a set of buttons with the |
| * same <code>ButtonGroup</code> object means that |
| * turning "on" one of those buttons |
| * turns off all other buttons in the group. |
| * <p> |
| * A <code>ButtonGroup</code> can be used with |
| * any set of objects that inherit from <code>AbstractButton</code>. |
| * Typically a button group contains instances of |
| * <code>JRadioButton</code>, |
| * <code>JRadioButtonMenuItem</code>, |
| * or <code>JToggleButton</code>. |
| * It wouldn't make sense to put an instance of |
| * <code>JButton</code> or <code>JMenuItem</code> |
| * in a button group |
| * because <code>JButton</code> and <code>JMenuItem</code> |
| * don't implement the selected state. |
| * <p> |
| * Initially, all buttons in the group are unselected. |
| * <p> |
| * For examples and further information on using button groups see |
| * <a href="http://docs.oracle.com/javase/tutorial/uiswing/components/button.html#radiobutton">How to Use Radio Buttons</a>, |
| * a section in <em>The Java Tutorial</em>. |
| * <p> |
| * <strong>Warning:</strong> |
| * 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 JavaBeans™ |
| * has been added to the <code>java.beans</code> package. |
| * Please see {@link java.beans.XMLEncoder}. |
| * |
| * @author Jeff Dinkins |
| * @since 1.2 |
| */ |
| @SuppressWarnings("serial") |
| public class ButtonGroup implements Serializable { |
| |
| /** |
| * The list of buttons participating in this group. |
| */ |
| protected Vector<AbstractButton> buttons = new Vector<AbstractButton>(); |
| |
| /** |
| * The current selection. |
| */ |
| ButtonModel selection = null; |
| |
| /** |
| * Creates a new <code>ButtonGroup</code>. |
| */ |
| public ButtonGroup() {} |
| |
| /** |
| * Adds the button to the group. |
| * @param b the button to be added |
| */ |
| public void add(AbstractButton b) { |
| if(b == null) { |
| return; |
| } |
| buttons.addElement(b); |
| |
| if (b.isSelected()) { |
| if (selection == null) { |
| selection = b.getModel(); |
| } else { |
| b.setSelected(false); |
| } |
| } |
| |
| b.getModel().setGroup(this); |
| } |
| |
| /** |
| * Removes the button from the group. |
| * @param b the button to be removed |
| */ |
| public void remove(AbstractButton b) { |
| if(b == null) { |
| return; |
| } |
| buttons.removeElement(b); |
| if(b.getModel() == selection) { |
| selection = null; |
| } |
| b.getModel().setGroup(null); |
| } |
| |
| /** |
| * Clears the selection such that none of the buttons |
| * in the <code>ButtonGroup</code> are selected. |
| * |
| * @since 1.6 |
| */ |
| public void clearSelection() { |
| if (selection != null) { |
| ButtonModel oldSelection = selection; |
| selection = null; |
| oldSelection.setSelected(false); |
| } |
| } |
| |
| /** |
| * Returns all the buttons that are participating in |
| * this group. |
| * @return an <code>Enumeration</code> of the buttons in this group |
| */ |
| public Enumeration<AbstractButton> getElements() { |
| return buttons.elements(); |
| } |
| |
| /** |
| * Returns the model of the selected button. |
| * @return the selected button model |
| */ |
| public ButtonModel getSelection() { |
| return selection; |
| } |
| |
| /** |
| * Sets the selected value for the <code>ButtonModel</code>. |
| * Only one button in the group may be selected at a time. |
| * @param m the <code>ButtonModel</code> |
| * @param b <code>true</code> if this button is to be |
| * selected, otherwise <code>false</code> |
| */ |
| public void setSelected(ButtonModel m, boolean b) { |
| if (b && m != null && m != selection) { |
| ButtonModel oldSelection = selection; |
| selection = m; |
| if (oldSelection != null) { |
| oldSelection.setSelected(false); |
| } |
| m.setSelected(true); |
| } |
| } |
| |
| /** |
| * Returns whether a {@code ButtonModel} is selected. |
| * |
| * @param m an isntance of {@code ButtonModel} |
| * @return {@code true} if the button is selected, |
| * otherwise returns {@code false} |
| */ |
| public boolean isSelected(ButtonModel m) { |
| return (m == selection); |
| } |
| |
| /** |
| * Returns the number of buttons in the group. |
| * @return the button count |
| * @since 1.3 |
| */ |
| public int getButtonCount() { |
| if (buttons == null) { |
| return 0; |
| } else { |
| return buttons.size(); |
| } |
| } |
| |
| } |