/*
* 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
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*/
package javax.swing;
import java.beans.JavaBean;
import java.beans.BeanProperty;
import java.io.ObjectOutputStream;
import java.io.IOException;
import javax.accessibility.*;
/**
* A menu item that can be selected or deselected. If selected, the menu
* item typically appears with a checkmark next to it. If unselected or
* deselected, the menu item appears without a checkmark. Like a regular
* menu item, a check box menu item can have either text or a graphic
* icon associated with it, or both.
* <p>
* Either <code>isSelected</code>/<code>setSelected</code> or
* <code>getState</code>/<code>setState</code> can be used
* to determine/specify the menu item's selection state. The
* preferred methods are <code>isSelected</code> and
* <code>setSelected</code>, which work for all menus and buttons.
* The <code>getState</code> and <code>setState</code> methods exist for
* compatibility with other component sets.
* <p>
* Menu items 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 menu item has many benefits beyond directly
* configuring a menu item. 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>
* Some times it is required to select several check box menu items from a menu.
* In this case it is useful that clicking on one check box menu item does not
* close the menu. Such behavior can be controlled either by client
* {@link JComponent#putClientProperty} or the Look and Feel
* {@link UIManager#put} property named
* {@code "CheckBoxMenuItem.doNotCloseOnMouseClick"}. The default value is
* {@code false}. Setting the property to {@code true} prevents the menu from
* closing when it is clicked by the mouse. If the client property is set its
* value is always used; otherwise the {@literal L&F} property is queried.
* Note: some {@code L&F}s may ignore this property. All built-in {@code L&F}s
* inherit this behaviour.
* <p>
* For further information and examples of using check box menu items,
* see <a
href="https://docs.oracle.com/javase/tutorial/uiswing/components/menu.html">How to Use Menus</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}.
*
* @author Georges Saab
* @author David Karlton
* @since 1.2
*/
@JavaBean(description = "A menu item which can be selected or deselected.")
@SwingContainer(false)
@SuppressWarnings("serial") // Same-version serialization only
public class JCheckBoxMenuItem extends JMenuItem implements SwingConstants,
Accessible
{
/**
* @see #getUIClassID
* @see #readObject
*/
private static final String uiClassID = "CheckBoxMenuItemUI";
/**
* Creates an initially unselected check box menu item with no set text or icon.
*/
public JCheckBoxMenuItem() {
this(null, null, false);
}
/**
* Creates an initially unselected check box menu item with an icon.
*
* @param icon the icon of the {@code JCheckBoxMenuItem}.
*/
public JCheckBoxMenuItem(Icon icon) {
this(null, icon, false);
}
/**
* Creates an initially unselected check box menu item with text.
*
* @param text the text of the {@code JCheckBoxMenuItem}
*/
public JCheckBoxMenuItem(String text) {
this(text, null, false);
}
/**
* Creates a menu item whose properties are taken from the
* Action supplied.
*
* @param a the action of the {@code JCheckBoxMenuItem}
* @since 1.3
*/
public JCheckBoxMenuItem(Action a) {
this();
setAction(a);
}
/**
* Creates an initially unselected check box menu item with the specified text and icon.
*
* @param text the text of the {@code JCheckBoxMenuItem}
* @param icon the icon of the {@code JCheckBoxMenuItem}
*/
public JCheckBoxMenuItem(String text, Icon icon) {
this(text, icon, false);
}
/**
* Creates a check box menu item with the specified text and selection state.
*
* @param text the text of the check box menu item.
* @param b the selected state of the check box menu item
*/
public JCheckBoxMenuItem(String text, boolean b) {
this(text, null, b);
}
/**
* Creates a check box menu item with the specified text, icon, and selection state.
*
* @param text the text of the check box menu item
* @param icon the icon of the check box menu item
* @param b the selected state of the check box menu item
*/
public JCheckBoxMenuItem(String text, Icon icon, boolean b) {
super(text, icon);
setModel(new JToggleButton.ToggleButtonModel());
setSelected(b);
setFocusable(false);
}
/**
* Returns the name of the L&F class
* that renders this component.
*
* @return the string "CheckBoxMenuItemUI"
* @see JComponent#getUIClassID
* @see UIDefaults#getUI
*/
@BeanProperty(bound = false)
public String getUIClassID() {
return uiClassID;
}
/**
* Returns the selected-state of the item. This method
* exists for AWT compatibility only. New code should
* use isSelected() instead.
*
* @return true if the item is selected
*/
public boolean getState() {
return isSelected();
}
/**
* Sets the selected-state of the item. This method
* exists for AWT compatibility only. New code should
* use setSelected() instead.
*
* @param b a boolean value indicating the item's
* selected-state, where true=selected
*/
@BeanProperty(bound = false, hidden = true, description
= "The selection state of the check box menu item")
public synchronized void setState(boolean b) {
setSelected(b);
}
/**
* Returns an array (length 1) containing the check box menu item
* label or null if the check box is not selected.
*
* @return an array containing one Object -- the text of the menu item
* -- if the item is selected; otherwise null
*/
@BeanProperty(bound = false)
public Object[] getSelectedObjects() {
if (isSelected() == false)
return null;
Object[] selectedObjects = new Object[1];
selectedObjects[0] = getText();
return selectedObjects;
}
/**
* 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 JCheckBoxMenuItem. 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 JCheckBoxMenuItem.
*/
protected String paramString() {
return super.paramString();
}
/**
* Overriden to return true, JCheckBoxMenuItem supports
* the selected state.
*/
boolean shouldUpdateSelectedStateFromAction() {
return true;
}
/////////////////
// Accessibility support
////////////////
/**
* Gets the AccessibleContext associated with this JCheckBoxMenuItem.
* For JCheckBoxMenuItems, the AccessibleContext takes the form of an
* AccessibleJCheckBoxMenuItem.
* A new AccessibleJCheckBoxMenuItem instance is created if necessary.
*
* @return an AccessibleJCheckBoxMenuItem that serves as the
* AccessibleContext of this AccessibleJCheckBoxMenuItem
*/
@BeanProperty(bound = false)
public AccessibleContext getAccessibleContext() {
if (accessibleContext == null) {
accessibleContext = new AccessibleJCheckBoxMenuItem();
}
return accessibleContext;
}
/**
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