This example Java source code file (JPopupMenu.java) is included in the alvinalexander.com
"Java Source Code
Warehouse" project. The intent of this project is to help you "Learn
Java by Example" TM.
/*
* Copyright (c) 1997, 2013, 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.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
import java.beans.*;
import java.util.Locale;
import java.util.Vector;
import java.util.Hashtable;
import javax.accessibility.*;
import javax.swing.plaf.PopupMenuUI;
import javax.swing.plaf.ComponentUI;
import javax.swing.plaf.basic.BasicComboPopup;
import javax.swing.event.*;
import sun.awt.SunToolkit;
import sun.security.util.SecurityConstants;
import java.applet.Applet;
/**
* An implementation of a popup menu -- a small window that pops up
* and displays a series of choices. A <code>JPopupMenu is used for the
* menu that appears when the user selects an item on the menu bar.
* It is also used for "pull-right" menu that appears when the
* selects a menu item that activates it. Finally, a <code>JPopupMenu
* can also be used anywhere else you want a menu to appear. For
* example, when the user right-clicks in a specified area.
* <p>
* For information and examples of using popup menus, see
* <a
href="http://docs.oracle.com/javase/tutorial/uiswing/components/menu.html">How to Use Menus</a>
* in <em>The Java Tutorial.
* <p>
* <strong>Warning: Swing is not thread safe. For more
* information see <a
* href="package-summary.html#threading">Swing's Threading
* Policy</a>.
* <p>
* <strong>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 JavaBeans™
* has been added to the <code>java.beans package.
* Please see {@link java.beans.XMLEncoder}.
*
* @beaninfo
* attribute: isContainer false
* description: A small window that pops up and displays a series of choices.
*
* @author Georges Saab
* @author David Karlton
* @author Arnaud Weber
*/
@SuppressWarnings("serial")
public class JPopupMenu extends JComponent implements Accessible,MenuElement {
/**
* @see #getUIClassID
* @see #readObject
*/
private static final String uiClassID = "PopupMenuUI";
/**
* Key used in AppContext to determine if light way popups are the default.
*/
private static final Object defaultLWPopupEnabledKey =
new StringBuffer("JPopupMenu.defaultLWPopupEnabledKey");
/** Bug#4425878-Property javax.swing.adjustPopupLocationToFit introduced */
static boolean popupPostionFixDisabled = false;
static {
popupPostionFixDisabled = java.security.AccessController.doPrivileged(
new sun.security.action.GetPropertyAction(
"javax.swing.adjustPopupLocationToFit","")).equals("false");
}
transient Component invoker;
transient Popup popup;
transient Frame frame;
private int desiredLocationX,desiredLocationY;
private String label = null;
private boolean paintBorder = true;
private Insets margin = null;
/**
* Used to indicate if lightweight popups should be used.
*/
private boolean lightWeightPopup = true;
/*
* Model for the selected subcontrol.
*/
private SingleSelectionModel selectionModel;
/* Lock object used in place of class object for synchronization.
* (4187686)
*/
private static final Object classLock = new Object();
/* diagnostic aids -- should be false for production builds. */
private static final boolean TRACE = false; // trace creates and disposes
private static final boolean VERBOSE = false; // show reuse hits/misses
private static final boolean DEBUG = false; // show bad params, misc.
/**
* Sets the default value of the <code>lightWeightPopupEnabled
* property.
*
* @param aFlag <code>true if popups can be lightweight,
* otherwise <code>false
* @see #getDefaultLightWeightPopupEnabled
* @see #setLightWeightPopupEnabled
*/
public static void setDefaultLightWeightPopupEnabled(boolean aFlag) {
SwingUtilities.appContextPut(defaultLWPopupEnabledKey,
Boolean.valueOf(aFlag));
}
/**
* Gets the <code>defaultLightWeightPopupEnabled property,
* which by default is <code>true.
*
* @return the value of the <code>defaultLightWeightPopupEnabled
* property
*
* @see #setDefaultLightWeightPopupEnabled
*/
public static boolean getDefaultLightWeightPopupEnabled() {
Boolean b = (Boolean)
SwingUtilities.appContextGet(defaultLWPopupEnabledKey);
if (b == null) {
SwingUtilities.appContextPut(defaultLWPopupEnabledKey,
Boolean.TRUE);
return true;
}
return b.booleanValue();
}
/**
* Constructs a <code>JPopupMenu without an "invoker".
*/
public JPopupMenu() {
this(null);
}
/**
* Constructs a <code>JPopupMenu with the specified title.
*
* @param label the string that a UI may use to display as a title
* for the popup menu.
*/
public JPopupMenu(String label) {
this.label = label;
lightWeightPopup = getDefaultLightWeightPopupEnabled();
setSelectionModel(new DefaultSingleSelectionModel());
enableEvents(AWTEvent.MOUSE_EVENT_MASK);
setFocusTraversalKeysEnabled(false);
updateUI();
}
/**
* Returns the look and feel (L&F) object that renders this component.
*
* @return the <code>PopupMenuUI object that renders this component
*/
public PopupMenuUI getUI() {
return (PopupMenuUI)ui;
}
/**
* Sets the L&F object that renders this component.
*
* @param ui the new <code>PopupMenuUI L&F object
* @see UIDefaults#getUI
* @beaninfo
* bound: true
* hidden: true
* attribute: visualUpdate true
* description: The UI object that implements the Component's LookAndFeel.
*/
public void setUI(PopupMenuUI ui) {
super.setUI(ui);
}
/**
* Resets the UI property to a value from the current look and feel.
*
* @see JComponent#updateUI
*/
public void updateUI() {
setUI((PopupMenuUI)UIManager.getUI(this));
}
/**
* Returns the name of the L&F class that renders this component.
*
* @return the string "PopupMenuUI"
* @see JComponent#getUIClassID
* @see UIDefaults#getUI
*/
public String getUIClassID() {
return uiClassID;
}
protected void processFocusEvent(FocusEvent evt) {
super.processFocusEvent(evt);
}
/**
* Processes key stroke events such as mnemonics and accelerators.
*
* @param evt the key event to be processed
*/
protected void processKeyEvent(KeyEvent evt) {
MenuSelectionManager.defaultManager().processKeyEvent(evt);
if (evt.isConsumed()) {
return;
}
super.processKeyEvent(evt);
}
/**
* Returns the model object that handles single selections.
*
* @return the <code>selectionModel property
* @see SingleSelectionModel
*/
public SingleSelectionModel getSelectionModel() {
return selectionModel;
}
/**
* Sets the model object to handle single selections.
*
* @param model the new <code>SingleSelectionModel
* @see SingleSelectionModel
* @beaninfo
* description: The selection model for the popup menu
* expert: true
*/
public void setSelectionModel(SingleSelectionModel model) {
selectionModel = model;
}
/**
* Appends the specified menu item to the end of this menu.
*
* @param menuItem the <code>JMenuItem to add
* @return the <code>JMenuItem added
*/
public JMenuItem add(JMenuItem menuItem) {
super.add(menuItem);
return menuItem;
}
/**
* Creates a new menu item with the specified text and appends
* it to the end of this menu.
*
* @param s the string for the menu item to be added
*/
public JMenuItem add(String s) {
return add(new JMenuItem(s));
}
/**
* Appends a new menu item to the end of the menu which
* dispatches the specified <code>Action object.
*
* @param a the <code>Action to add to the menu
* @return the new menu item
* @see Action
*/
public JMenuItem add(Action a) {
JMenuItem mi = createActionComponent(a);
mi.setAction(a);
add(mi);
return mi;
}
/**
* Returns an point which has been adjusted to take into account of the
* desktop bounds, taskbar and multi-monitor configuration.
* <p>
* This adustment may be cancelled by invoking the application with
* -Djavax.swing.adjustPopupLocationToFit=false
*/
Point adjustPopupLocationToFitScreen(int xPosition, int yPosition) {
Point popupLocation = new Point(xPosition, yPosition);
if(popupPostionFixDisabled == true || GraphicsEnvironment.isHeadless()) {
return popupLocation;
}
// Get screen bounds
Rectangle scrBounds;
GraphicsConfiguration gc = getCurrentGraphicsConfiguration(popupLocation);
Toolkit toolkit = Toolkit.getDefaultToolkit();
if(gc != null) {
// If we have GraphicsConfiguration use it to get screen bounds
scrBounds = gc.getBounds();
} else {
// If we don't have GraphicsConfiguration use primary screen
scrBounds = new Rectangle(toolkit.getScreenSize());
}
// Calculate the screen size that popup should fit
Dimension popupSize = JPopupMenu.this.getPreferredSize();
long popupRightX = (long)popupLocation.x + (long)popupSize.width;
long popupBottomY = (long)popupLocation.y + (long)popupSize.height;
int scrWidth = scrBounds.width;
int scrHeight = scrBounds.height;
if (!canPopupOverlapTaskBar()) {
// Insets include the task bar. Take them into account.
Insets scrInsets = toolkit.getScreenInsets(gc);
scrBounds.x += scrInsets.left;
scrBounds.y += scrInsets.top;
scrWidth -= scrInsets.left + scrInsets.right;
scrHeight -= scrInsets.top + scrInsets.bottom;
}
int scrRightX = scrBounds.x + scrWidth;
int scrBottomY = scrBounds.y + scrHeight;
// Ensure that popup menu fits the screen
if (popupRightX > (long) scrRightX) {
popupLocation.x = scrRightX - popupSize.width;
}
if (popupBottomY > (long) scrBottomY) {
popupLocation.y = scrBottomY - popupSize.height;
}
if (popupLocation.x < scrBounds.x) {
popupLocation.x = scrBounds.x;
}
if (popupLocation.y < scrBounds.y) {
popupLocation.y = scrBounds.y;
}
return popupLocation;
}
/**
* Tries to find GraphicsConfiguration
* that contains the mouse cursor position.
* Can return null.
*/
private GraphicsConfiguration getCurrentGraphicsConfiguration(
Point popupLocation) {
GraphicsConfiguration gc = null;
GraphicsEnvironment ge =
GraphicsEnvironment.getLocalGraphicsEnvironment();
GraphicsDevice[] gd = ge.getScreenDevices();
for(int i = 0; i < gd.length; i++) {
if(gd[i].getType() == GraphicsDevice.TYPE_RASTER_SCREEN) {
GraphicsConfiguration dgc =
gd[i].getDefaultConfiguration();
if(dgc.getBounds().contains(popupLocation)) {
gc = dgc;
break;
}
}
}
// If not found and we have invoker, ask invoker about his gc
if(gc == null && getInvoker() != null) {
gc = getInvoker().getGraphicsConfiguration();
}
return gc;
}
/**
* Returns whether popup is allowed to be shown above the task bar.
*/
static boolean canPopupOverlapTaskBar() {
boolean result = true;
Toolkit tk = Toolkit.getDefaultToolkit();
if (tk instanceof SunToolkit) {
result = ((SunToolkit)tk).canPopupOverlapTaskBar();
}
return result;
}
/**
* Factory method which creates the <code>JMenuItem for
* <code>Actions added to the JPopupMenu.
*
* @param a the <code>Action for the menu item to be added
* @return the new menu item
* @see Action
*
* @since 1.3
*/
protected JMenuItem createActionComponent(Action a) {
JMenuItem mi = new JMenuItem() {
protected PropertyChangeListener createActionPropertyChangeListener(Action a) {
PropertyChangeListener pcl = createActionChangeListener(this);
if (pcl == null) {
pcl = super.createActionPropertyChangeListener(a);
}
return pcl;
}
};
mi.setHorizontalTextPosition(JButton.TRAILING);
mi.setVerticalTextPosition(JButton.CENTER);
return mi;
}
/**
* Returns a properly configured <code>PropertyChangeListener
* which updates the control as changes to the <code>Action occur.
*/
protected PropertyChangeListener createActionChangeListener(JMenuItem b) {
return b.createActionPropertyChangeListener0(b.getAction());
}
/**
* Removes the component at the specified index from this popup menu.
*
* @param pos the position of the item to be removed
* @exception IllegalArgumentException if the value of
* <code>pos < 0, or if the value of
* <code>pos is greater than the
* number of items
*/
public void remove(int pos) {
if (pos < 0) {
throw new IllegalArgumentException("index less than zero.");
}
if (pos > getComponentCount() -1) {
throw new IllegalArgumentException("index greater than the number of items.");
}
super.remove(pos);
}
/**
* Sets the value of the <code>lightWeightPopupEnabled property,
* which by default is <code>true.
* By default, when a look and feel displays a popup,
* it can choose to
* use a lightweight (all-Java) popup.
* Lightweight popup windows are more efficient than heavyweight
* (native peer) windows,
* but lightweight and heavyweight components do not mix well in a GUI.
* If your application mixes lightweight and heavyweight components,
* you should disable lightweight popups.
* Some look and feels might always use heavyweight popups,
* no matter what the value of this property.
*
* @param aFlag <code>false to disable lightweight popups
* @beaninfo
* description: Determines whether lightweight popups are used when possible
* expert: true
*
* @see #isLightWeightPopupEnabled
*/
public void setLightWeightPopupEnabled(boolean aFlag) {
// NOTE: this use to set the flag on a shared JPopupMenu, which meant
// this effected ALL JPopupMenus.
lightWeightPopup = aFlag;
}
/**
* Gets the <code>lightWeightPopupEnabled property.
*
* @return the value of the <code>lightWeightPopupEnabled property
* @see #setLightWeightPopupEnabled
*/
public boolean isLightWeightPopupEnabled() {
return lightWeightPopup;
}
/**
* Returns the popup menu's label
*
* @return a string containing the popup menu's label
* @see #setLabel
*/
public String getLabel() {
return label;
}
/**
* Sets the popup menu's label. Different look and feels may choose
* to display or not display this.
*
* @param label a string specifying the label for the popup menu
*
* @see #setLabel
* @beaninfo
* description: The label for the popup menu.
* bound: true
*/
public void setLabel(String label) {
String oldValue = this.label;
this.label = label;
firePropertyChange("label", oldValue, label);
if (accessibleContext != null) {
accessibleContext.firePropertyChange(
AccessibleContext.ACCESSIBLE_VISIBLE_DATA_PROPERTY,
oldValue, label);
}
invalidate();
repaint();
}
/**
* Appends a new separator at the end of the menu.
*/
public void addSeparator() {
add( new JPopupMenu.Separator() );
}
/**
* Inserts a menu item for the specified <code>Action object at
* a given position.
*
* @param a the <code>Action object to insert
* @param index specifies the position at which to insert the
* <code>Action, where 0 is the first
* @exception IllegalArgumentException if <code>index < 0
* @see Action
*/
public void insert(Action a, int index) {
JMenuItem mi = createActionComponent(a);
mi.setAction(a);
insert(mi, index);
}
/**
* Inserts the specified component into the menu at a given
* position.
*
* @param component the <code>Component to insert
* @param index specifies the position at which
* to insert the component, where 0 is the first
* @exception IllegalArgumentException if <code>index < 0
*/
public void insert(Component component, int index) {
if (index < 0) {
throw new IllegalArgumentException("index less than zero.");
}
int nitems = getComponentCount();
// PENDING(ges): Why not use an array?
Vector<Component> tempItems = new Vector();
/* Remove the item at index, nitems-index times
storing them in a temporary vector in the
order they appear on the menu.
*/
for (int i = index ; i < nitems; i++) {
tempItems.addElement(getComponent(index));
remove(index);
}
add(component);
/* Add the removed items back to the menu, they are
already in the correct order in the temp vector.
*/
for (Component tempItem : tempItems) {
add(tempItem);
}
}
/**
* Adds a <code>PopupMenu listener.
*
* @param l the <code>PopupMenuListener to add
*/
public void addPopupMenuListener(PopupMenuListener l) {
listenerList.add(PopupMenuListener.class,l);
}
/**
* Removes a <code>PopupMenu listener.
*
* @param l the <code>PopupMenuListener to remove
*/
public void removePopupMenuListener(PopupMenuListener l) {
listenerList.remove(PopupMenuListener.class,l);
}
/**
* Returns an array of all the <code>PopupMenuListeners added
* to this JMenuItem with addPopupMenuListener().
*
* @return all of the <code>PopupMenuListeners added or an empty
* array if no listeners have been added
* @since 1.4
*/
public PopupMenuListener[] getPopupMenuListeners() {
return listenerList.getListeners(PopupMenuListener.class);
}
/**
* Adds a <code>MenuKeyListener to the popup menu.
*
* @param l the <code>MenuKeyListener to be added
* @since 1.5
*/
public void addMenuKeyListener(MenuKeyListener l) {
listenerList.add(MenuKeyListener.class, l);
}
/**
* Removes a <code>MenuKeyListener from the popup menu.
*
* @param l the <code>MenuKeyListener to be removed
* @since 1.5
*/
public void removeMenuKeyListener(MenuKeyListener l) {
listenerList.remove(MenuKeyListener.class, l);
}
/**
* Returns an array of all the <code>MenuKeyListeners added
* to this JPopupMenu with addMenuKeyListener().
*
* @return all of the <code>MenuKeyListeners added or an empty
* array if no listeners have been added
* @since 1.5
*/
public MenuKeyListener[] getMenuKeyListeners() {
return listenerList.getListeners(MenuKeyListener.class);
}
/**
* Notifies <code>PopupMenuListeners that this popup menu will
* become visible.
*/
protected void firePopupMenuWillBecomeVisible() {
Object[] listeners = listenerList.getListenerList();
PopupMenuEvent e=null;
for (int i = listeners.length-2; i>=0; i-=2) {
if (listeners[i]==PopupMenuListener.class) {
if (e == null)
e = new PopupMenuEvent(this);
((PopupMenuListener)listeners[i+1]).popupMenuWillBecomeVisible(e);
}
}
}
/**
* Notifies <code>PopupMenuListeners that this popup menu will
* become invisible.
*/
protected void firePopupMenuWillBecomeInvisible() {
Object[] listeners = listenerList.getListenerList();
PopupMenuEvent e=null;
for (int i = listeners.length-2; i>=0; i-=2) {
if (listeners[i]==PopupMenuListener.class) {
if (e == null)
e = new PopupMenuEvent(this);
((PopupMenuListener)listeners[i+1]).popupMenuWillBecomeInvisible(e);
}
}
}
/**
* Notifies <code>PopupMenuListeners that this popup menu is
* cancelled.
*/
protected void firePopupMenuCanceled() {
Object[] listeners = listenerList.getListenerList();
PopupMenuEvent e=null;
for (int i = listeners.length-2; i>=0; i-=2) {
if (listeners[i]==PopupMenuListener.class) {
if (e == null)
e = new PopupMenuEvent(this);
((PopupMenuListener)listeners[i+1]).popupMenuCanceled(e);
}
}
}
/**
* Always returns true since popups, by definition, should always
* be on top of all other windows.
* @return true
*/
// package private
boolean alwaysOnTop() {
return true;
}
/**
* Lays out the container so that it uses the minimum space
* needed to display its contents.
*/
public void pack() {
if(popup != null) {
Dimension pref = getPreferredSize();
if (pref == null || pref.width != getWidth() ||
pref.height != getHeight()) {
showPopup();
} else {
validate();
}
}
}
/**
* Sets the visibility of the popup menu.
*
* @param b true to make the popup visible, or false to
* hide it
* @beaninfo
* bound: true
* description: Makes the popup visible
*/
public void setVisible(boolean b) {
if (DEBUG) {
System.out.println("JPopupMenu.setVisible " + b);
}
// Is it a no-op?
if (b == isVisible())
return;
// if closing, first close all Submenus
if (b == false) {
// 4234793: This is a workaround because JPopupMenu.firePopupMenuCanceled is
// a protected method and cannot be called from BasicPopupMenuUI directly
// The real solution could be to make
// firePopupMenuCanceled public and call it directly.
Boolean doCanceled = (Boolean)getClientProperty("JPopupMenu.firePopupMenuCanceled");
if (doCanceled != null && doCanceled == Boolean.TRUE) {
putClientProperty("JPopupMenu.firePopupMenuCanceled", Boolean.FALSE);
firePopupMenuCanceled();
}
getSelectionModel().clearSelection();
} else {
// This is a popup menu with MenuElement children,
// set selection path before popping up!
if (isPopupMenu()) {
MenuElement me[] = new MenuElement[1];
me[0] = this;
MenuSelectionManager.defaultManager().setSelectedPath(me);
}
}
if(b) {
firePopupMenuWillBecomeVisible();
showPopup();
firePropertyChange("visible", Boolean.FALSE, Boolean.TRUE);
} else if(popup != null) {
firePopupMenuWillBecomeInvisible();
popup.hide();
popup = null;
firePropertyChange("visible", Boolean.TRUE, Boolean.FALSE);
// 4694797: When popup menu is made invisible, selected path
// should be cleared
if (isPopupMenu()) {
MenuSelectionManager.defaultManager().clearSelectedPath();
}
}
}
/**
* Retrieves <code>Popup instance from the
* <code>PopupMenuUI that has had show invoked on
* it. If the current <code>popup is non-null,
* this will invoke <code>dispose of it, and then
* <code>show the new one.
* <p>
* This does NOT fire any events, it is up the caller to dispatch
* the necessary events.
*/
private void showPopup() {
Popup oldPopup = popup;
if (oldPopup != null) {
oldPopup.hide();
}
PopupFactory popupFactory = PopupFactory.getSharedInstance();
if (isLightWeightPopupEnabled()) {
popupFactory.setPopupType(PopupFactory.LIGHT_WEIGHT_POPUP);
}
else {
popupFactory.setPopupType(PopupFactory.HEAVY_WEIGHT_POPUP);
}
// adjust the location of the popup
Point p = adjustPopupLocationToFitScreen(desiredLocationX,desiredLocationY);
desiredLocationX = p.x;
desiredLocationY = p.y;
Popup newPopup = getUI().getPopup(this, desiredLocationX,
desiredLocationY);
popupFactory.setPopupType(PopupFactory.LIGHT_WEIGHT_POPUP);
popup = newPopup;
newPopup.show();
}
/**
* Returns true if the popup menu is visible (currently
* being displayed).
*/
public boolean isVisible() {
return popup != null;
}
/**
* Sets the location of the upper left corner of the
* popup menu using x, y coordinates.
* <p>
* The method changes the geometry-related data. Therefore,
* the native windowing system may ignore such requests, or it may modify
* the requested data, so that the {@code JPopupMenu} object is placed and sized
* in a way that corresponds closely to the desktop settings.
*
* @param x the x coordinate of the popup's new position
* in the screen's coordinate space
* @param y the y coordinate of the popup's new position
* in the screen's coordinate space
* @beaninfo
* description: The location of the popup menu.
*/
public void setLocation(int x, int y) {
int oldX = desiredLocationX;
int oldY = desiredLocationY;
desiredLocationX = x;
desiredLocationY = y;
if(popup != null && (x != oldX || y != oldY)) {
showPopup();
}
}
/**
* Returns true if the popup menu is a standalone popup menu
* rather than the submenu of a <code>JMenu.
*
* @return true if this menu is a standalone popup menu, otherwise false
*/
private boolean isPopupMenu() {
return ((invoker != null) && !(invoker instanceof JMenu));
}
/**
* Returns the component which is the 'invoker' of this
* popup menu.
*
* @return the <code>Component in which the popup menu is displayed
*/
public Component getInvoker() {
return this.invoker;
}
/**
* Sets the invoker of this popup menu -- the component in which
* the popup menu menu is to be displayed.
*
* @param invoker the <code>Component in which the popup
* menu is displayed
* @beaninfo
* description: The invoking component for the popup menu
* expert: true
*/
public void setInvoker(Component invoker) {
Component oldInvoker = this.invoker;
this.invoker = invoker;
if ((oldInvoker != this.invoker) && (ui != null)) {
ui.uninstallUI(this);
ui.installUI(this);
}
invalidate();
}
/**
* Displays the popup menu at the position x,y in the coordinate
* space of the component invoker.
*
* @param invoker the component in whose space the popup menu is to appear
* @param x the x coordinate in invoker's coordinate space at which
* the popup menu is to be displayed
* @param y the y coordinate in invoker's coordinate space at which
* the popup menu is to be displayed
*/
public void show(Component invoker, int x, int y) {
if (DEBUG) {
System.out.println("in JPopupMenu.show " );
}
setInvoker(invoker);
Frame newFrame = getFrame(invoker);
if (newFrame != frame) {
// Use the invoker's frame so that events
// are propagated properly
if (newFrame!=null) {
this.frame = newFrame;
if(popup != null) {
setVisible(false);
}
}
}
Point invokerOrigin;
if (invoker != null) {
invokerOrigin = invoker.getLocationOnScreen();
// To avoid integer overflow
long lx, ly;
lx = ((long) invokerOrigin.x) +
((long) x);
ly = ((long) invokerOrigin.y) +
((long) y);
if(lx > Integer.MAX_VALUE) lx = Integer.MAX_VALUE;
if(lx < Integer.MIN_VALUE) lx = Integer.MIN_VALUE;
if(ly > Integer.MAX_VALUE) ly = Integer.MAX_VALUE;
if(ly < Integer.MIN_VALUE) ly = Integer.MIN_VALUE;
setLocation((int) lx, (int) ly);
} else {
setLocation(x, y);
}
setVisible(true);
}
/**
* Returns the popup menu which is at the root of the menu system
* for this popup menu.
*
* @return the topmost grandparent <code>JPopupMenu
*/
JPopupMenu getRootPopupMenu() {
JPopupMenu mp = this;
while((mp!=null) && (mp.isPopupMenu()!=true) &&
(mp.getInvoker() != null) &&
(mp.getInvoker().getParent() != null) &&
(mp.getInvoker().getParent() instanceof JPopupMenu)
) {
mp = (JPopupMenu) mp.getInvoker().getParent();
}
return mp;
}
/**
* Returns the component at the specified index.
*
* @param i the index of the component, where 0 is the first
* @return the <code>Component at that index
* @deprecated replaced by {@link java.awt.Container#getComponent(int)}
*/
@Deprecated
public Component getComponentAtIndex(int i) {
return getComponent(i);
}
/**
* Returns the index of the specified component.
*
* @param c the <code>Component to find
* @return the index of the component, where 0 is the first;
* or -1 if the component is not found
*/
public int getComponentIndex(Component c) {
int ncomponents = this.getComponentCount();
Component[] component = this.getComponents();
for (int i = 0 ; i < ncomponents ; i++) {
Component comp = component[i];
if (comp == c)
return i;
}
return -1;
}
/**
* Sets the size of the Popup window using a <code>Dimension object.
* This is equivalent to <code>setPreferredSize(d).
*
* @param d the <code>Dimension specifying the new size
* of this component.
* @beaninfo
* description: The size of the popup menu
*/
public void setPopupSize(Dimension d) {
Dimension oldSize = getPreferredSize();
setPreferredSize(d);
if (popup != null) {
Dimension newSize = getPreferredSize();
if (!oldSize.equals(newSize)) {
showPopup();
}
}
}
/**
* Sets the size of the Popup window to the specified width and
* height. This is equivalent to
* <code>setPreferredSize(new Dimension(width, height)).
*
* @param width the new width of the Popup in pixels
* @param height the new height of the Popup in pixels
* @beaninfo
* description: The size of the popup menu
*/
public void setPopupSize(int width, int height) {
setPopupSize(new Dimension(width, height));
}
/**
* Sets the currently selected component, This will result
* in a change to the selection model.
*
* @param sel the <code>Component to select
* @beaninfo
* description: The selected component on the popup menu
* expert: true
* hidden: true
*/
public void setSelected(Component sel) {
SingleSelectionModel model = getSelectionModel();
int index = getComponentIndex(sel);
model.setSelectedIndex(index);
}
/**
* Checks whether the border should be painted.
*
* @return true if the border is painted, false otherwise
* @see #setBorderPainted
*/
public boolean isBorderPainted() {
return paintBorder;
}
/**
* Sets whether the border should be painted.
*
* @param b if true, the border is painted.
* @see #isBorderPainted
* @beaninfo
* description: Is the border of the popup menu painted
*/
public void setBorderPainted(boolean b) {
paintBorder = b;
repaint();
}
/**
* Paints the popup menu's border if the <code>borderPainted
* property is <code>true.
* @param g the <code>Graphics object
*
* @see JComponent#paint
* @see JComponent#setBorder
*/
protected void paintBorder(Graphics g) {
if (isBorderPainted()) {
super.paintBorder(g);
}
}
/**
* Returns the margin, in pixels, between the popup menu's border and
* its containers.
*
* @return an <code>Insets object containing the margin values.
*/
public Insets getMargin() {
if(margin == null) {
return new Insets(0,0,0,0);
} else {
return margin;
}
}
/**
* Examines the list of menu items to determine whether
* <code>popup is a popup menu.
*
* @param popup a <code>JPopupMenu
* @return true if <code>popup
*/
boolean isSubPopupMenu(JPopupMenu popup) {
int ncomponents = this.getComponentCount();
Component[] component = this.getComponents();
for (int i = 0 ; i < ncomponents ; i++) {
Component comp = component[i];
if (comp instanceof JMenu) {
JMenu menu = (JMenu)comp;
JPopupMenu subPopup = menu.getPopupMenu();
if (subPopup == popup)
return true;
if (subPopup.isSubPopupMenu(popup))
return true;
}
}
return false;
}
private static Frame getFrame(Component c) {
Component w = c;
while(!(w instanceof Frame) && (w!=null)) {
w = w.getParent();
}
return (Frame)w;
}
/**
* Returns a string representation of this <code>JPopupMenu.
* 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 a string representation of this <code>JPopupMenu.
*/
protected String paramString() {
String labelString = (label != null ?
label : "");
String paintBorderString = (paintBorder ?
"true" : "false");
String marginString = (margin != null ?
margin.toString() : "");
String lightWeightPopupEnabledString = (isLightWeightPopupEnabled() ?
"true" : "false");
return super.paramString() +
",desiredLocationX=" + desiredLocationX +
",desiredLocationY=" + desiredLocationY +
",label=" + labelString +
",lightWeightPopupEnabled=" + lightWeightPopupEnabledString +
",margin=" + marginString +
",paintBorder=" + paintBorderString;
}
/////////////////
// Accessibility support
////////////////
/**
* Gets the AccessibleContext associated with this JPopupMenu.
* For JPopupMenus, the AccessibleContext takes the form of an
* AccessibleJPopupMenu.
* A new AccessibleJPopupMenu instance is created if necessary.
*
* @return an AccessibleJPopupMenu that serves as the
* AccessibleContext of this JPopupMenu
*/
public AccessibleContext getAccessibleContext() {
if (accessibleContext == null) {
accessibleContext = new AccessibleJPopupMenu();
}
return accessibleContext;
}
/**
* This class implements accessibility support for the
* <code>JPopupMenu class. It provides an implementation of the
* Java Accessibility API appropriate to popup menu user-interface
* elements.
*/
@SuppressWarnings("serial")
protected class AccessibleJPopupMenu extends AccessibleJComponent
implements PropertyChangeListener {
/**
* AccessibleJPopupMenu constructor
*
* @since 1.5
*/
protected AccessibleJPopupMenu() {
JPopupMenu.this.addPropertyChangeListener(this);
}
/**
* Get the role of this object.
*
* @return an instance of AccessibleRole describing the role of
* the object
*/
public AccessibleRole getAccessibleRole() {
return AccessibleRole.POPUP_MENU;
}
/**
* This method gets called when a bound property is changed.
* @param e A <code>PropertyChangeEvent object describing
* the event source and the property that has changed. Must not be null.
*
* @throws NullPointerException if the parameter is null.
* @since 1.5
*/
public void propertyChange(PropertyChangeEvent e) {
String propertyName = e.getPropertyName();
if (propertyName == "visible") {
if (e.getOldValue() == Boolean.FALSE &&
e.getNewValue() == Boolean.TRUE) {
handlePopupIsVisibleEvent(true);
} else if (e.getOldValue() == Boolean.TRUE &&
e.getNewValue() == Boolean.FALSE) {
handlePopupIsVisibleEvent(false);
}
}
}
/*
* Handles popup "visible" PropertyChangeEvent
*/
private void handlePopupIsVisibleEvent(boolean visible) {
if (visible) {
// notify listeners that the popup became visible
firePropertyChange(ACCESSIBLE_STATE_PROPERTY,
null, AccessibleState.VISIBLE);
// notify listeners that a popup list item is selected
fireActiveDescendant();
} else {
// notify listeners that the popup became hidden
firePropertyChange(ACCESSIBLE_STATE_PROPERTY,
AccessibleState.VISIBLE, null);
}
}
/*
* Fires AccessibleActiveDescendant PropertyChangeEvent to notify listeners
* on the popup menu invoker that a popup list item has been selected
*/
private void fireActiveDescendant() {
if (JPopupMenu.this instanceof BasicComboPopup) {
// get the popup list
JList<?> popupList = ((BasicComboPopup)JPopupMenu.this).getList();
if (popupList == null) {
return;
}
// get the first selected item
AccessibleContext ac = popupList.getAccessibleContext();
AccessibleSelection selection = ac.getAccessibleSelection();
if (selection == null) {
return;
}
Accessible a = selection.getAccessibleSelection(0);
if (a == null) {
return;
}
AccessibleContext selectedItem = a.getAccessibleContext();
// fire the event with the popup invoker as the source.
if (selectedItem != null && invoker != null) {
AccessibleContext invokerContext = invoker.getAccessibleContext();
if (invokerContext != null) {
// Check invokerContext because Component.getAccessibleContext
// returns null. Classes that extend Component are responsible
// for returning a non-null AccessibleContext.
invokerContext.firePropertyChange(
ACCESSIBLE_ACTIVE_DESCENDANT_PROPERTY,
null, selectedItem);
}
}
}
}
} // inner class AccessibleJPopupMenu
////////////
// Serialization support.
////////////
private void writeObject(ObjectOutputStream s) throws IOException {
Vector<Object> values = new Vector
