| /* | |
| * Copyright (c) 1995, 2022, 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 java.awt; | |
| import java.awt.event.ActionListener; | |
| import java.awt.event.ItemEvent; | |
| import java.awt.event.ItemListener; | |
| import java.awt.peer.CheckboxMenuItemPeer; | |
| import java.io.IOException; | |
| import java.io.ObjectInputStream; | |
| import java.io.ObjectOutputStream; | |
| import java.io.Serial; | |
| import java.util.EventListener; | |
| import javax.accessibility.Accessible; | |
| import javax.accessibility.AccessibleAction; | |
| import javax.accessibility.AccessibleContext; | |
| import javax.accessibility.AccessibleRole; | |
| import javax.accessibility.AccessibleValue; | |
| import sun.awt.AWTAccessor; | |
| /** | |
| * This class represents a check box that can be included in a menu. | |
| * Selecting the check box in the menu changes its state from | |
| * "on" to "off" or from "off" to "on." | |
| * <p> | |
| * The following picture depicts a menu which contains an instance | |
| * of {@code CheckBoxMenuItem}: | |
| * <p> | |
| * <img src="doc-files/MenuBar-1.gif" | |
| * alt="Menu labeled Examples, containing items Basic, Simple, Check, and More | |
| * Examples. The Check item is a CheckBoxMenuItem instance, in the off state." | |
| * style="margin: 7px 10px;"> | |
| * <p> | |
| * The item labeled {@code Check} shows a check box menu item | |
| * in its "off" state. | |
| * <p> | |
| * When a check box menu item is selected, AWT sends an item event to | |
| * the item. Since the event is an instance of {@code ItemEvent}, | |
| * the {@code processEvent} method examines the event and passes | |
| * it along to {@code processItemEvent}. The latter method redirects | |
| * the event to any {@code ItemListener} objects that have | |
| * registered an interest in item events generated by this menu item. | |
| * | |
| * @author Sami Shaio | |
| * @see java.awt.event.ItemEvent | |
| * @see java.awt.event.ItemListener | |
| * @since 1.0 | |
| */ | |
| public class CheckboxMenuItem extends MenuItem implements ItemSelectable, Accessible { | |
| static { | |
| /* ensure that the necessary native libraries are loaded */ | |
| Toolkit.loadLibraries(); | |
| if (!GraphicsEnvironment.isHeadless()) { | |
| initIDs(); | |
| } | |
| AWTAccessor.setCheckboxMenuItemAccessor( | |
| new AWTAccessor.CheckboxMenuItemAccessor() { | |
| public boolean getState(CheckboxMenuItem cmi) { | |
| return cmi.state; | |
| } | |
| }); | |
| } | |
| /** | |
| * The state of a checkbox menu item | |
| * @serial | |
| * @see #getState() | |
| * @see #setState(boolean) | |
| */ | |
| private volatile boolean state; | |
| private transient volatile ItemListener itemListener; | |
| private static final String base = "chkmenuitem"; | |
| private static int nameCounter = 0; | |
| /** | |
| * Use serialVersionUID from JDK 1.1 for interoperability. | |
| */ | |
| @Serial | |
| private static final long serialVersionUID = 6190621106981774043L; | |
| /** | |
| * Create a check box menu item with an empty label. | |
| * The item's state is initially set to "off." | |
| * @throws HeadlessException if GraphicsEnvironment.isHeadless() | |
| * returns true | |
| * @see java.awt.GraphicsEnvironment#isHeadless | |
| * @since 1.1 | |
| */ | |
| public CheckboxMenuItem() throws HeadlessException { | |
| this("", false); | |
| } | |
| /** | |
| * Create a check box menu item with the specified label. | |
| * The item's state is initially set to "off." | |
| * @param label a string label for the check box menu item, | |
| * or {@code null} for an unlabeled menu item. | |
| * @throws HeadlessException if GraphicsEnvironment.isHeadless() | |
| * returns true | |
| * @see java.awt.GraphicsEnvironment#isHeadless | |
| */ | |
| public CheckboxMenuItem(String label) throws HeadlessException { | |
| this(label, false); | |
| } | |
| /** | |
| * Create a check box menu item with the specified label and state. | |
| * @param label a string label for the check box menu item, | |
| * or {@code null} for an unlabeled menu item. | |
| * @param state the initial state of the menu item, where | |
| * {@code true} indicates "on" and | |
| * {@code false} indicates "off." | |
| * @throws HeadlessException if GraphicsEnvironment.isHeadless() | |
| * returns true | |
| * @see java.awt.GraphicsEnvironment#isHeadless | |
| * @since 1.1 | |
| */ | |
| public CheckboxMenuItem(String label, boolean state) | |
| throws HeadlessException { | |
| super(label); | |
| this.state = state; | |
| } | |
| /** | |
| * Construct a name for this MenuComponent. Called by getName() when | |
| * the name is null. | |
| */ | |
| String constructComponentName() { | |
| synchronized (CheckboxMenuItem.class) { | |
| return base + nameCounter++; | |
| } | |
| } | |
| /** | |
| * Creates the peer of the checkbox item. This peer allows us to | |
| * change the look of the checkbox item without changing its | |
| * functionality. | |
| * Most applications do not call this method directly. | |
| * @see java.awt.Component#getToolkit() | |
| */ | |
| public void addNotify() { | |
| synchronized (getTreeLock()) { | |
| if (peer == null) | |
| peer = getComponentFactory().createCheckboxMenuItem(this); | |
| super.addNotify(); | |
| } | |
| } | |
| /** | |
| * Determines whether the state of this check box menu item | |
| * is "on" or "off." | |
| * | |
| * @return the state of this check box menu item, where | |
| * {@code true} indicates "on" and | |
| * {@code false} indicates "off" | |
| * @see #setState | |
| */ | |
| public boolean getState() { | |
| return state; | |
| } | |
| /** | |
| * Sets this check box menu item to the specified state. | |
| * The boolean value {@code true} indicates "on" while | |
| * {@code false} indicates "off." | |
| * | |
| * <p>Note that this method should be primarily used to | |
| * initialize the state of the check box menu item. | |
| * Programmatically setting the state of the check box | |
| * menu item will <i>not</i> trigger | |
| * an {@code ItemEvent}. The only way to trigger an | |
| * {@code ItemEvent} is by user interaction. | |
| * | |
| * @param b {@code true} if the check box | |
| * menu item is on, otherwise {@code false} | |
| * @see #getState | |
| */ | |
| public synchronized void setState(boolean b) { | |
| state = b; | |
| CheckboxMenuItemPeer peer = (CheckboxMenuItemPeer)this.peer; | |
| if (peer != null) { | |
| peer.setState(b); | |
| } | |
| } | |
| /** | |
| * Returns the array (length 1) containing the checkbox menu item | |
| * label or null if the checkbox is not selected. | |
| * @see ItemSelectable | |
| */ | |
| public synchronized Object[] getSelectedObjects() { | |
| if (state) { | |
| Object[] items = new Object[1]; | |
| items[0] = label; | |
| return items; | |
| } | |
| return null; | |
| } | |
| /** | |
| * Adds the specified item listener to receive item events from | |
| * this check box menu item. Item events are sent in response to user | |
| * actions, but not in response to calls to setState(). | |
| * If l is null, no exception is thrown and no action is performed. | |
| * <p>Refer to <a href="doc-files/AWTThreadIssues.html#ListenersThreads" | |
| * >AWT Threading Issues</a> for details on AWT's threading model. | |
| * | |
| * @param l the item listener | |
| * @see #removeItemListener | |
| * @see #getItemListeners | |
| * @see #setState | |
| * @see java.awt.event.ItemEvent | |
| * @see java.awt.event.ItemListener | |
| * @since 1.1 | |
| */ | |
| public synchronized void addItemListener(ItemListener l) { | |
| if (l == null) { | |
| return; | |
| } | |
| itemListener = AWTEventMulticaster.add(itemListener, l); | |
| newEventsOnly = true; | |
| } | |
| /** | |
| * Removes the specified item listener so that it no longer receives | |
| * item events from this check box menu item. | |
| * If l is null, no exception is thrown and no action is performed. | |
| * <p>Refer to <a href="doc-files/AWTThreadIssues.html#ListenersThreads" | |
| * >AWT Threading Issues</a> for details on AWT's threading model. | |
| * | |
| * @param l the item listener | |
| * @see #addItemListener | |
| * @see #getItemListeners | |
| * @see java.awt.event.ItemEvent | |
| * @see java.awt.event.ItemListener | |
| * @since 1.1 | |
| */ | |
| public synchronized void removeItemListener(ItemListener l) { | |
| if (l == null) { | |
| return; | |
| } | |
| itemListener = AWTEventMulticaster.remove(itemListener, l); | |
| } | |
| /** | |
| * Returns an array of all the item listeners | |
| * registered on this checkbox menuitem. | |
| * | |
| * @return all of this checkbox menuitem's {@code ItemListener}s | |
| * or an empty array if no item | |
| * listeners are currently registered | |
| * | |
| * @see #addItemListener | |
| * @see #removeItemListener | |
| * @see java.awt.event.ItemEvent | |
| * @see java.awt.event.ItemListener | |
| * @since 1.4 | |
| */ | |
| public synchronized ItemListener[] getItemListeners() { | |
| return getListeners(ItemListener.class); | |
| } | |
| /** | |
| * Returns an array of all the objects currently registered | |
| * as <code><em>Foo</em>Listener</code>s | |
| * upon this {@code CheckboxMenuItem}. | |
| * <code><em>Foo</em>Listener</code>s are registered using the | |
| * <code>add<em>Foo</em>Listener</code> method. | |
| * | |
| * <p> | |
| * You can specify the {@code listenerType} argument | |
| * with a class literal, such as | |
| * <code><em>Foo</em>Listener.class</code>. | |
| * For example, you can query a | |
| * {@code CheckboxMenuItem c} | |
| * for its item listeners with the following code: | |
| * | |
| * <pre>ItemListener[] ils = (ItemListener[])(c.getListeners(ItemListener.class));</pre> | |
| * | |
| * If no such listeners exist, this method returns an empty array. | |
| * | |
| * @param listenerType the type of listeners requested; this parameter | |
| * should specify an interface that descends from | |
| * {@code java.util.EventListener} | |
| * @return an array of all objects registered as | |
| * <code><em>Foo</em>Listener</code>s on this checkbox menuitem, | |
| * or an empty array if no such | |
| * listeners have been added | |
| * @throws ClassCastException if {@code listenerType} | |
| * doesn't specify a class or interface that implements | |
| * {@code java.util.EventListener} | |
| * | |
| * @see #getItemListeners | |
| * @since 1.3 | |
| */ | |
| public <T extends EventListener> T[] getListeners(Class<T> listenerType) { | |
| EventListener l = null; | |
| if (listenerType == ItemListener.class) { | |
| l = itemListener; | |
| } else { | |
| return super.getListeners(listenerType); | |
| } | |
| return AWTEventMulticaster.getListeners(l, listenerType); | |
| } | |
| // REMIND: remove when filtering is done at lower level | |
| boolean eventEnabled(AWTEvent e) { | |
| if (e.id == ItemEvent.ITEM_STATE_CHANGED) { | |
| if ((eventMask & AWTEvent.ITEM_EVENT_MASK) != 0 || | |
| itemListener != null) { | |
| return true; | |
| } | |
| return false; | |
| } | |
| return super.eventEnabled(e); | |
| } | |
| /** | |
| * Processes events on this check box menu item. | |
| * If the event is an instance of {@code ItemEvent}, | |
| * this method invokes the {@code processItemEvent} method. | |
| * If the event is not an item event, | |
| * it invokes {@code processEvent} on the superclass. | |
| * <p> | |
| * Check box menu items currently support only item events. | |
| * <p>Note that if the event parameter is {@code null} | |
| * the behavior is unspecified and may result in an | |
| * exception. | |
| * | |
| * @param e the event | |
| * @see java.awt.event.ItemEvent | |
| * @see #processItemEvent | |
| * @since 1.1 | |
| */ | |
| protected void processEvent(AWTEvent e) { | |
| if (e instanceof ItemEvent) { | |
| processItemEvent((ItemEvent)e); | |
| return; | |
| } | |
| super.processEvent(e); | |
| } | |
| /** | |
| * Processes item events occurring on this check box menu item by | |
| * dispatching them to any registered {@code ItemListener} objects. | |
| * <p> | |
| * This method is not called unless item events are | |
| * enabled for this menu item. Item events are enabled | |
| * when one of the following occurs: | |
| * <ul> | |
| * <li>An {@code ItemListener} object is registered | |
| * via {@code addItemListener}. | |
| * <li>Item events are enabled via {@code enableEvents}. | |
| * </ul> | |
| * <p>Note that if the event parameter is {@code null} | |
| * the behavior is unspecified and may result in an | |
| * exception. | |
| * | |
| * @param e the item event | |
| * @see java.awt.event.ItemEvent | |
| * @see java.awt.event.ItemListener | |
| * @see #addItemListener | |
| * @see java.awt.MenuItem#enableEvents | |
| * @since 1.1 | |
| */ | |
| protected void processItemEvent(ItemEvent e) { | |
| ItemListener listener = itemListener; | |
| if (listener != null) { | |
| listener.itemStateChanged(e); | |
| } | |
| } | |
| /* | |
| * Post an ItemEvent and toggle state. | |
| */ | |
| void doMenuEvent(long when, int modifiers) { | |
| setState(!state); | |
| Toolkit.getEventQueue().postEvent( | |
| new ItemEvent(this, ItemEvent.ITEM_STATE_CHANGED, | |
| getLabel(), | |
| state ? ItemEvent.SELECTED : | |
| ItemEvent.DESELECTED)); | |
| } | |
| /** | |
| * Returns a string representing the state of this | |
| * {@code CheckBoxMenuItem}. 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}. | |
| * | |
| * @return the parameter string of this check box menu item | |
| */ | |
| public String paramString() { | |
| return super.paramString() + ",state=" + state; | |
| } | |
| /* Serialization support. | |
| */ | |
| /** | |
| * Serialized data version. | |
| * @serial | |
| */ | |
| private int checkboxMenuItemSerializedDataVersion = 1; | |
| /** | |
| * Writes default serializable fields to stream. Writes | |
| * a list of serializable {@code ItemListeners} | |
| * as optional data. The non-serializable | |
| * {@code ItemListeners} are detected and | |
| * no attempt is made to serialize them. | |
| * | |
| * @param s the {@code ObjectOutputStream} to write | |
| * @throws IOException if an I/O error occurs | |
| * @serialData {@code null} terminated sequence of | |
| * 0 or more pairs; the pair consists of a {@code String} | |
| * and an {@code Object}; the {@code String} indicates | |
| * the type of object and is one of the following: | |
| * {@code itemListenerK} indicating an | |
| * {@code ItemListener} object | |
| * | |
| * @see AWTEventMulticaster#save(ObjectOutputStream, String, EventListener) | |
| * @see java.awt.Component#itemListenerK | |
| * @see #readObject(ObjectInputStream) | |
| */ | |
| @Serial | |
| private void writeObject(ObjectOutputStream s) | |
| throws java.io.IOException | |
| { | |
| s.defaultWriteObject(); | |
| AWTEventMulticaster.save(s, itemListenerK, itemListener); | |
| s.writeObject(null); | |
| } | |
| /** | |
| * Reads the {@code ObjectInputStream} and if it | |
| * isn't {@code null} adds a listener to receive | |
| * item events fired by the {@code Checkbox} menu item. | |
| * Unrecognized keys or values will be ignored. | |
| * | |
| * @param s the {@code ObjectInputStream} to read | |
| * @throws ClassNotFoundException if the class of a serialized object could | |
| * not be found | |
| * @throws IOException if an I/O error occurs | |
| * | |
| * @see #removeActionListener(ActionListener) | |
| * @see #addActionListener(ActionListener) | |
| * @see #writeObject(ObjectOutputStream) | |
| */ | |
| @Serial | |
| private void readObject(ObjectInputStream s) | |
| throws ClassNotFoundException, IOException | |
| { | |
| s.defaultReadObject(); | |
| Object keyOrNull; | |
| while(null != (keyOrNull = s.readObject())) { | |
| String key = ((String)keyOrNull).intern(); | |
| if (itemListenerK == key) | |
| addItemListener((ItemListener)(s.readObject())); | |
| else // skip value for unrecognized key | |
| s.readObject(); | |
| } | |
| } | |
| /** | |
| * Initialize JNI field and method IDs | |
| */ | |
| private static native void initIDs(); | |
| ///////////////// | |
| // Accessibility support | |
| //////////////// | |
| /** | |
| * Gets the AccessibleContext associated with this CheckboxMenuItem. | |
| * For checkbox menu items, the AccessibleContext takes the | |
| * form of an AccessibleAWTCheckboxMenuItem. | |
| * A new AccessibleAWTCheckboxMenuItem is created if necessary. | |
| * | |
| * @return an AccessibleAWTCheckboxMenuItem that serves as the | |
| * AccessibleContext of this CheckboxMenuItem | |
| * @since 1.3 | |
| */ | |
| public AccessibleContext getAccessibleContext() { | |
| if (accessibleContext == null) { | |
| accessibleContext = new AccessibleAWTCheckboxMenuItem(); | |
| } | |
| return accessibleContext; | |
| } | |
| /** | |
| * Inner class of CheckboxMenuItem used to provide default support for | |
| * accessibility. This class is not meant to be used directly by | |
| * application developers, but is instead meant only to be | |
| * subclassed by menu component developers. | |
| * <p> | |
| * This class implements accessibility support for the | |
| * {@code CheckboxMenuItem} class. It provides an implementation | |
| * of the Java Accessibility API appropriate to checkbox menu item | |
| * user-interface elements. | |
| * @since 1.3 | |
| */ | |
| protected class AccessibleAWTCheckboxMenuItem extends AccessibleAWTMenuItem | |
| implements AccessibleAction, AccessibleValue | |
| { | |
| /** | |
| * Use serialVersionUID from JDK 1.3 for interoperability. | |
| */ | |
| @Serial | |
| private static final long serialVersionUID = -1122642964303476L; | |
| /** | |
| * Constructs an {@code AccessibleAWTCheckboxMenuItem}. | |
| */ | |
| protected AccessibleAWTCheckboxMenuItem() {} | |
| /** | |
| * Get the AccessibleAction associated with this object. In the | |
| * implementation of the Java Accessibility API for this class, | |
| * return this object, which is responsible for implementing the | |
| * AccessibleAction interface on behalf of itself. | |
| * | |
| * @return this object | |
| */ | |
| public AccessibleAction getAccessibleAction() { | |
| return this; | |
| } | |
| /** | |
| * Get the AccessibleValue associated with this object. In the | |
| * implementation of the Java Accessibility API for this class, | |
| * return this object, which is responsible for implementing the | |
| * AccessibleValue interface on behalf of itself. | |
| * | |
| * @return this object | |
| */ | |
| public AccessibleValue getAccessibleValue() { | |
| return this; | |
| } | |
| /** | |
| * Returns the number of Actions available in this object. | |
| * If there is more than one, the first one is the "default" | |
| * action. | |
| * | |
| * @return the number of Actions in this object | |
| */ | |
| public int getAccessibleActionCount() { | |
| return 0; // To be fully implemented in a future release | |
| } | |
| /** | |
| * Return a description of the specified action of the object. | |
| * | |
| * @param i zero-based index of the actions | |
| */ | |
| public String getAccessibleActionDescription(int i) { | |
| return null; // To be fully implemented in a future release | |
| } | |
| /** | |
| * Perform the specified Action on the object | |
| * | |
| * @param i zero-based index of actions | |
| * @return true if the action was performed; otherwise false. | |
| */ | |
| public boolean doAccessibleAction(int i) { | |
| return false; // To be fully implemented in a future release | |
| } | |
| /** | |
| * Get the value of this object as a Number. If the value has not been | |
| * set, the return value will be null. | |
| * | |
| * @return value of the object | |
| * @see #setCurrentAccessibleValue | |
| */ | |
| public Number getCurrentAccessibleValue() { | |
| return null; // To be fully implemented in a future release | |
| } | |
| /** | |
| * Set the value of this object as a Number. | |
| * | |
| * @return true if the value was set; otherwise false | |
| * @see #getCurrentAccessibleValue | |
| */ | |
| public boolean setCurrentAccessibleValue(Number n) { | |
| return false; // To be fully implemented in a future release | |
| } | |
| /** | |
| * Get the minimum value of this object as a Number. | |
| * | |
| * @return Minimum value of the object; null if this object does not | |
| * have a minimum value | |
| * @see #getMaximumAccessibleValue | |
| */ | |
| public Number getMinimumAccessibleValue() { | |
| return null; // To be fully implemented in a future release | |
| } | |
| /** | |
| * Get the maximum value of this object as a Number. | |
| * | |
| * @return Maximum value of the object; null if this object does not | |
| * have a maximum value | |
| * @see #getMinimumAccessibleValue | |
| */ | |
| public Number getMaximumAccessibleValue() { | |
| return null; // To be fully implemented in a future release | |
| } | |
| /** | |
| * Get the role of this object. | |
| * | |
| * @return an instance of AccessibleRole describing the role of the | |
| * object | |
| */ | |
| public AccessibleRole getAccessibleRole() { | |
| return AccessibleRole.CHECK_BOX; | |
| } | |
| } // class AccessibleAWTMenuItem | |
| } |