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/* * 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.*; import java.awt.event.*; import java.beans.JavaBean; import java.beans.BeanProperty; import javax.swing.plaf.*; import javax.accessibility.*; import java.io.ObjectOutputStream; import java.io.IOException; import java.util.Iterator; /** * An implementation of a two-state button. * The <code>JRadioButton</code> and <code>JCheckBox</code> classes * are subclasses of this class. * For information on using them see * <a href="https://docs.oracle.com/javase/tutorial/uiswing/components/button.html">How to Use Buttons, Check Boxes, and Radio Buttons</a>, * a section in <em>The Java Tutorial</em>. * <p> * Buttons can be configured, and to some degree controlled, by * <code><a href="Action.html">Action</a></code>s. Using an * <code>Action</code> with a button has many benefits beyond directly * configuring a button. Refer to <a href="Action.html#buttonActions"> * Swing Components Supporting <code>Action</code></a> for more * details, and you can find more information in <a * href="https://docs.oracle.com/javase/tutorial/uiswing/misc/action.html">How * to Use Actions</a>, a section in <em>The Java Tutorial</em>. * <p> * <strong>Warning:</strong> Swing is not thread safe. For more * information see <a * href="package-summary.html#threading">Swing's Threading * Policy</a>. * <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}. * * @see JRadioButton * @see JCheckBox * @author Jeff Dinkins * @since 1.2 */ @JavaBean(defaultProperty = "UIClassID", description = "An implementation of a two-state button.") @SwingContainer(false) @SuppressWarnings("serial") // Same-version serialization only public class JToggleButton extends AbstractButton implements Accessible { /** * @see #getUIClassID * @see #readObject */ private static final String uiClassID = "ToggleButtonUI"; /** * Creates an initially unselected toggle button * without setting the text or image. */ public JToggleButton() { this(null, null, false); } /** * Creates an initially unselected toggle button * with the specified image but no text. * * @param icon the image that the button should display */ public JToggleButton(Icon icon) { this(null, icon, false); } /** * Creates a toggle 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 JToggleButton(Icon icon, boolean selected) { this(null, icon, selected); } /** * Creates an unselected toggle button with the specified text. * * @param text the string displayed on the toggle button */ public JToggleButton(String text) { this(text, null, false); } /** * Creates a toggle button with the specified text * and selection state. * * @param text the string displayed on the toggle button * @param selected if true, the button is initially selected; * otherwise, the button is initially unselected */ public JToggleButton(String text, boolean selected) { this(text, null, selected); } /** * Creates a toggle button where properties are taken from the * Action supplied. * * @param a an instance of an {@code Action} * @since 1.3 */ public JToggleButton(Action a) { this(); setAction(a); } /** * Creates a toggle button that has the specified text and image, * and that is initially unselected. * * @param text the string displayed on the button * @param icon the image that the button should display */ public JToggleButton(String text, Icon icon) { this(text, icon, false); } /** * Creates a toggle button with the specified text, image, and * selection state. * * @param text the text of the toggle button * @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 JToggleButton(String text, Icon icon, boolean selected) { // Create the model setModel(new ToggleButtonModel()); model.setSelected(selected); // initialize init(text, icon); } /** * 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 a string that specifies the name of the l&f class * that renders this component. * * @return the string "ToggleButtonUI" * @see JComponent#getUIClassID * @see UIDefaults#getUI */ @BeanProperty(bound = false, description = "A string that specifies the name of the L&F class") public String getUIClassID() { return uiClassID; } /** * Overriden to return true, JToggleButton supports * the selected state. */ boolean shouldUpdateSelectedStateFromAction() { return true; } private JToggleButton getGroupSelection(FocusEvent.Cause cause) { switch (cause) { case ACTIVATION: case TRAVERSAL: case TRAVERSAL_UP: case TRAVERSAL_DOWN: case TRAVERSAL_FORWARD: case TRAVERSAL_BACKWARD: ButtonModel model = getModel(); JToggleButton selection = this; if (model != null) { ButtonGroup group = model.getGroup(); if (group != null && group.getSelection() != null && !group.isSelected(model)) { Iterator<AbstractButton> iterator = group.getElements().asIterator(); while (iterator.hasNext()) { AbstractButton member = iterator.next(); if (group.isSelected(member.getModel())) { if (member instanceof JToggleButton && member.isVisible() && member.isDisplayable() && member.isEnabled() && member.isFocusable()) { selection = (JToggleButton) member; } break; } } } } return selection; default: return this; } } /** * If this toggle button is a member of the {@link ButtonGroup} which has * another toggle button which is selected and can be the focus owner, * and the focus cause argument denotes window activation or focus * traversal action of any direction the result of the method execution * is the same as calling * {@link Component#requestFocus(FocusEvent.Cause)} on the toggle button * selected in the group. * In all other cases the result of the method is the same as calling * {@link Component#requestFocus(FocusEvent.Cause)} on this toggle button. * * @param cause the cause why the focus is requested * @see ButtonGroup * @see Component#requestFocus(FocusEvent.Cause) * @see FocusEvent.Cause * * @since 9 */ @Override public void requestFocus(FocusEvent.Cause cause) { getGroupSelection(cause).requestFocusUnconditionally(cause); } private void requestFocusUnconditionally(FocusEvent.Cause cause) { super.requestFocus(cause); } /** * If this toggle button is a member of the {@link ButtonGroup} which has * another toggle button which is selected and can be the focus owner, * and the focus cause argument denotes window activation or focus * traversal action of any direction the result of the method execution * is the same as calling * {@link Component#requestFocusInWindow(FocusEvent.Cause)} on the toggle * button selected in the group. * In all other cases the result of the method is the same as calling * {@link Component#requestFocusInWindow(FocusEvent.Cause)} on this toggle * button. * * @param cause the cause why the focus is requested * @see ButtonGroup * @see Component#requestFocusInWindow(FocusEvent.Cause) * @see FocusEvent.Cause * * @since 9 */ public boolean requestFocusInWindow(FocusEvent.Cause cause) { return getGroupSelection(cause).requestFocusInWindowUnconditionally(cause); } private boolean requestFocusInWindowUnconditionally(FocusEvent.Cause cause) { return super.requestFocusInWindow(cause); } // ********************************************************************* /** * The ToggleButton model * <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}. */ @SuppressWarnings("serial") // Same-version serialization only public static class ToggleButtonModel extends DefaultButtonModel { /** * Creates a new ToggleButton Model */ public ToggleButtonModel() { } /** * Checks if the button is selected. */ public boolean isSelected() { // if(getGroup() != null) { // return getGroup().isSelected(this); // } else { return (stateMask & SELECTED) != 0; // } } /** * Sets the selected state of the button. * @param b true selects the toggle button, * false deselects the toggle button. */ public void setSelected(boolean b) { ButtonGroup group = getGroup(); if (group != null) { // use the group model instead group.setSelected(this, b); b = group.isSelected(this); } if (isSelected() == b) { return; } if (b) { stateMask |= SELECTED; } else { stateMask &= ~SELECTED; } // Send ChangeEvent fireStateChanged(); // Send ItemEvent fireItemStateChanged(new ItemEvent(this, ItemEvent.ITEM_STATE_CHANGED, this, this.isSelected() ? ItemEvent.SELECTED : ItemEvent.DESELECTED)); } /** * Sets the pressed state of the toggle button. */ @SuppressWarnings("deprecation") public void setPressed(boolean b) { if ((isPressed() == b) || !isEnabled()) { return; } if (b == false && isArmed()) { setSelected(!this.isSelected()); } if (b) { stateMask |= PRESSED; } else { stateMask &= ~PRESSED; } fireStateChanged(); 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)); } } } /** * 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 JToggleButton. 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 <code>null</code>. * * @return a string representation of this JToggleButton. */ protected String paramString() { return super.paramString(); } ///////////////// // Accessibility support //////////////// /** * Gets the AccessibleContext associated with this JToggleButton. * For toggle buttons, the AccessibleContext takes the form of an * AccessibleJToggleButton. * A new AccessibleJToggleButton instance is created if necessary. * * @return an AccessibleJToggleButton that serves as the * AccessibleContext of this JToggleButton */ @BeanProperty(bound = false, expert = true, description = "The AccessibleContext associated with this ToggleButton.") public AccessibleContext getAccessibleContext() { if (accessibleContext == null) { accessibleContext = new AccessibleJToggleButton(); } return accessibleContext; } /** * This class implements accessibility support for the * <code>JToggleButton</code> class. It provides an implementation of the * Java Accessibility API appropriate to toggle button user-interface * elements. * <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}. */ @SuppressWarnings("serial") // Same-version serialization only protected class AccessibleJToggleButton extends AccessibleAbstractButton implements ItemListener { /** * Constructs {@code AccessibleJToggleButton} */ public AccessibleJToggleButton() { super(); JToggleButton.this.addItemListener(this); } /** * Fire accessible property change events when the state of the * toggle button changes. */ public void itemStateChanged(ItemEvent e) { JToggleButton tb = (JToggleButton) e.getSource(); if (JToggleButton.this.accessibleContext != null) { if (tb.isSelected()) { JToggleButton.this.accessibleContext.firePropertyChange( AccessibleContext.ACCESSIBLE_STATE_PROPERTY, null, AccessibleState.CHECKED); } else { JToggleButton.this.accessibleContext.firePropertyChange( AccessibleContext.ACCESSIBLE_STATE_PROPERTY, AccessibleState.CHECKED, null); } } } /** * Get the role of this object. * * @return an instance of AccessibleRole describing the role of the * object */ public AccessibleRole getAccessibleRole() { return AccessibleRole.TOGGLE_BUTTON; } } // inner class AccessibleJToggleButton }