JMenuItems that
* is displayed when the user selects an item on the JMenuBar.
* In addition to JMenuItems, a JMenu can
* also contain JSeparators.
*
* In essence, a menu is a button with an associated JPopupMenu.
* When the "button" is pressed, the JPopupMenu appears. If the
* "button" is on the JMenuBar, the menu is a top-level window.
* If the "button" is another menu item, then the JPopupMenu is
* "pull-right" menu.
*
* Menus can be configured, and to some degree controlled, by
* Actions. Using an
* Action with a menu has many benefits beyond directly
* configuring a menu. Refer to
* Swing Components Supporting Action for more
* details, and you can find more information in How
* to Use Actions, a section in The Java Tutorial.
*
* For information and examples of using menus see * How to Use Menus, * a section in The Java Tutorial. *
* Warning: Swing is not thread safe. For more * information see Swing's Threading * Policy. *
* 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 JavaBeansTM
* has been added to the java.beans package.
* Please see {@link java.beans.XMLEncoder}.
*
* @beaninfo
* attribute: isContainer true
* description: A popup window containing menu items displayed in a menu bar.
*
* @author Georges Saab
* @author David Karlton
* @author Arnaud Weber
* @see JMenuItem
* @see JSeparator
* @see JMenuBar
* @see JPopupMenu
*/
public class JMenu extends JMenuItem implements Accessible,MenuElement
{
/**
* @see #getUIClassID
* @see #readObject
*/
private static final String uiClassID = "MenuUI";
/*
* The popup menu portion of the menu.
*/
private JPopupMenu popupMenu;
/*
* The button's model listeners. Default is null.
*/
private ChangeListener menuChangeListener = null;
/*
* Only one MenuEvent is needed for each menu since the
* event's only state is the source property. The source of events
* generated is always "this". Default is null.
*/
private MenuEvent menuEvent = null;
/* Registry of listeners created for Action-JMenuItem
* linkage. This is needed so that references can
* be cleaned up at remove time to allow garbage collection
* Default is null.
*/
private static Hashtable listenerRegistry = null;
/*
* Used by the look and feel (L&F) code to handle
* implementation specific menu behaviors.
*/
private int delay;
/*
* Location of the popup component. Location is null
* if it was not customized by setMenuLocation
*/
private Point customMenuLocation = null;
/* 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.
/**
* Constructs a new JMenu with no text.
*/
public JMenu() {
this("");
}
/**
* Constructs a new JMenu with the supplied string
* as its text.
*
* @param s the text for the menu label
*/
public JMenu(String s) {
super(s);
}
/**
* Constructs a menu whose properties are taken from the
* Action supplied.
* @param a an Action
*
* @since 1.3
*/
public JMenu(Action a) {
this();
setAction(a);
}
/**
* Constructs a new JMenu with the supplied string as
* its text and specified as a tear-off menu or not.
*
* @param s the text for the menu label
* @param b can the menu be torn off (not yet implemented)
*/
public JMenu(String s, boolean b) {
this(s);
}
/**
* Overriden to do nothing. We want JMenu to be focusable, but
* JMenuItem doesn't want to be, thus we override this
* do nothing. We don't invoke setFocusable(true) after
* super's constructor has completed as this has the side effect that
* JMenu will be considered traversable via the
* keyboard, which we don't want. Making a Component traversable by
* the keyboard after invoking setFocusable(true) is OK,
* as setFocusable is new API
* and is speced as such, but internally we don't want to use it like
* this else we change the keyboard traversability.
*/
void initFocusability() {
}
/**
* Resets the UI property with a value from the current look and feel.
*
* @see JComponent#updateUI
*/
public void updateUI() {
setUI((MenuItemUI)UIManager.getUI(this));
if ( popupMenu != null )
{
popupMenu.setUI((PopupMenuUI)UIManager.getUI(popupMenu));
}
}
/**
* Returns the name of the L&F class that renders this component.
*
* @return the string "MenuUI"
* @see JComponent#getUIClassID
* @see UIDefaults#getUI
*/
public String getUIClassID() {
return uiClassID;
}
// public void repaint(long tm, int x, int y, int width, int height) {
// Thread.currentThread().dumpStack();
// super.repaint(tm,x,y,width,height);
// }
/**
* Sets the data model for the "menu button" -- the label
* that the user clicks to open or close the menu.
*
* @param newModel the ButtonModel
* @see #getModel
* @beaninfo
* description: The menu's model
* bound: true
* expert: true
* hidden: true
*/
public void setModel(ButtonModel newModel) {
ButtonModel oldModel = getModel();
super.setModel(newModel);
if (oldModel != null && menuChangeListener != null) {
oldModel.removeChangeListener(menuChangeListener);
menuChangeListener = null;
}
model = newModel;
if (newModel != null) {
menuChangeListener = createMenuChangeListener();
newModel.addChangeListener(menuChangeListener);
}
}
/**
* Returns true if the menu is currently selected (highlighted).
*
* @return true if the menu is selected, else false
*/
public boolean isSelected() {
return getModel().isSelected();
}
/**
* Sets the selection status of the menu.
*
* @param b true to select (highlight) the menu; false to de-select
* the menu
* @beaninfo
* description: When the menu is selected, its popup child is shown.
* expert: true
* hidden: true
*/
public void setSelected(boolean b) {
ButtonModel model = getModel();
boolean oldValue = model.isSelected();
// TIGER - 4840653
// Removed code which fired an AccessibleState.SELECTED
// PropertyChangeEvent since this resulted in two
// identical events being fired since
// AbstractButton.fireItemStateChanged also fires the
// same event. This caused screen readers to speak the
// name of the item twice.
if (b != model.isSelected()) {
getModel().setSelected(b);
}
}
/**
* Returns true if the menu's popup window is visible.
*
* @return true if the menu is visible, else false
*/
public boolean isPopupMenuVisible() {
ensurePopupMenuCreated();
return popupMenu.isVisible();
}
/**
* Sets the visibility of the menu's popup. If the menu is
* not enabled, this method will have no effect.
*
* @param b a boolean value -- true to make the menu visible,
* false to hide it
* @beaninfo
* description: The popup menu's visibility
* expert: true
* hidden: true
*/
public void setPopupMenuVisible(boolean b) {
if (DEBUG) {
System.out.println("in JMenu.setPopupMenuVisible " + b);
// Thread.dumpStack();
}
boolean isVisible = isPopupMenuVisible();
if (b != isVisible && (isEnabled() || !b)) {
ensurePopupMenuCreated();
if ((b==true) && isShowing()) {
// Set location of popupMenu (pulldown or pullright)
Point p = getCustomMenuLocation();
if (p == null) {
p = getPopupMenuOrigin();
}
getPopupMenu().show(this, p.x, p.y);
} else {
getPopupMenu().setVisible(false);
}
}
}
/**
* Computes the origin for the JMenu's popup menu.
* This method uses Look and Feel properties named
* Menu.menuPopupOffsetX,
* Menu.menuPopupOffsetY,
* Menu.submenuPopupOffsetX, and
* Menu.submenuPopupOffsetY
* to adjust the exact location of popup.
*
* @return a Point in the coordinate space of the
* menu which should be used as the origin
* of the JMenu's popup menu
*
* @since 1.3
*/
protected Point getPopupMenuOrigin() {
int x;
int y;
JPopupMenu pm = getPopupMenu();
// Figure out the sizes needed to caclulate the menu position
Dimension s = getSize();
Dimension pmSize = pm.getSize();
// For the first time the menu is popped up,
// the size has not yet been initiated
if (pmSize.width==0) {
pmSize = pm.getPreferredSize();
}
Point position = getLocationOnScreen();
Toolkit toolkit = Toolkit.getDefaultToolkit();
GraphicsConfiguration gc = getGraphicsConfiguration();
Rectangle screenBounds = new Rectangle(toolkit.getScreenSize());
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(position)) {
gc = dgc;
break;
}
}
}
if (gc != null) {
screenBounds = gc.getBounds();
// take screen insets (e.g. taskbar) into account
Insets screenInsets = toolkit.getScreenInsets(gc);
screenBounds.width -=
Math.abs(screenInsets.left + screenInsets.right);
screenBounds.height -=
Math.abs(screenInsets.top + screenInsets.bottom);
position.x -= Math.abs(screenInsets.left);
position.y -= Math.abs(screenInsets.top);
}
Container parent = getParent();
if (parent instanceof JPopupMenu) {
// We are a submenu (pull-right)
int xOffset = UIManager.getInt("Menu.submenuPopupOffsetX");
int yOffset = UIManager.getInt("Menu.submenuPopupOffsetY");
if( SwingUtilities.isLeftToRight(this) ) {
// First determine x:
x = s.width + xOffset; // Prefer placement to the right
if (position.x + x + pmSize.width >= screenBounds.width
+ screenBounds.x &&
// popup doesn't fit - place it wherever there's more room
screenBounds.width - s.width < 2*(position.x
- screenBounds.x)) {
x = 0 - xOffset - pmSize.width;
}
} else {
// First determine x:
x = 0 - xOffset - pmSize.width; // Prefer placement to the left
if (position.x + x < screenBounds.x &&
// popup doesn't fit - place it wherever there's more room
screenBounds.width - s.width > 2*(position.x -
screenBounds.x)) {
x = s.width + xOffset;
}
}
// Then the y:
y = yOffset; // Prefer dropping down
if (position.y + y + pmSize.height >= screenBounds.height
+ screenBounds.y &&
// popup doesn't fit - place it wherever there's more room
screenBounds.height - s.height < 2*(position.y
- screenBounds.y)) {
y = s.height - yOffset - pmSize.height;
}
} else {
// We are a toplevel menu (pull-down)
int xOffset = UIManager.getInt("Menu.menuPopupOffsetX");
int yOffset = UIManager.getInt("Menu.menuPopupOffsetY");
if( SwingUtilities.isLeftToRight(this) ) {
// First determine the x:
x = xOffset; // Extend to the right
if (position.x + x + pmSize.width >= screenBounds.width
+ screenBounds.x &&
// popup doesn't fit - place it wherever there's more room
screenBounds.width - s.width < 2*(position.x
- screenBounds.x)) {
x = s.width - xOffset - pmSize.width;
}
} else {
// First determine the x:
x = s.width - xOffset - pmSize.width; // Extend to the left
if (position.x + x < screenBounds.x &&
// popup doesn't fit - place it wherever there's more room
screenBounds.width - s.width > 2*(position.x
- screenBounds.x)) {
x = xOffset;
}
}
// Then the y:
y = s.height + yOffset; // Prefer dropping down
if (position.y + y + pmSize.height >= screenBounds.height &&
// popup doesn't fit - place it wherever there's more room
screenBounds.height - s.height < 2*(position.y
- screenBounds.y)) {
y = 0 - yOffset - pmSize.height; // Otherwise drop 'up'
}
}
return new Point(x,y);
}
/**
* Returns the suggested delay, in milliseconds, before submenus
* are popped up or down.
* Each look and feel (L&F) may determine its own policy for
* observing the delay property.
* In most cases, the delay is not observed for top level menus
* or while dragging. The default for delay is 0.
* This method is a property of the look and feel code and is used
* to manage the idiosyncracies of the various UI implementations.
*
*
* @return the delay property
*/
public int getDelay() {
return delay;
}
/**
* Sets the suggested delay before the menu's PopupMenu
* is popped up or down. Each look and feel (L&F) may determine
* it's own policy for observing the delay property. In most cases,
* the delay is not observed for top level menus or while dragging.
* This method is a property of the look and feel code and is used
* to manage the idiosyncracies of the various UI implementations.
*
* @param d the number of milliseconds to delay
* @exception IllegalArgumentException if d
* is less than 0
* @beaninfo
* description: The delay between menu selection and making the popup menu visible
* expert: true
*/
public void setDelay(int d) {
if (d < 0)
throw new IllegalArgumentException("Delay must be a positive integer");
delay = d;
}
/**
* The window-closing listener for the popup.
*
* @see WinListener
*/
protected WinListener popupListener;
private void ensurePopupMenuCreated() {
if (popupMenu == null) {
final JMenu thisMenu = this;
this.popupMenu = new JPopupMenu();
popupMenu.setInvoker(this);
popupListener = createWinListener(popupMenu);
}
}
/*
* Return the customized location of the popup component.
*/
private Point getCustomMenuLocation() {
return customMenuLocation;
}
/**
* Sets the location of the popup component.
*
* @param x the x coordinate of the popup's new position
* @param y the y coordinate of the popup's new position
*/
public void setMenuLocation(int x, int y) {
customMenuLocation = new Point(x, y);
if (popupMenu != null)
popupMenu.setLocation(x, y);
}
/**
* Appends a menu item to the end of this menu.
* Returns the menu item added.
*
* @param menuItem the JMenuitem to be added
* @return the JMenuItem added
*/
public JMenuItem add(JMenuItem menuItem) {
ensurePopupMenuCreated();
return popupMenu.add(menuItem);
}
/**
* Appends a component to the end of this menu.
* Returns the component added.
*
* @param c the Component to add
* @return the Component added
*/
public Component add(Component c) {
ensurePopupMenuCreated();
popupMenu.add(c);
return c;
}
/**
* Adds the specified component to this container at the given
* position. If index equals -1, the component will
* be appended to the end.
* @param c the Component to add
* @param index the position at which to insert the component
* @return the Component added
* @see #remove
* @see java.awt.Container#add(Component, int)
*/
public Component add(Component c, int index) {
ensurePopupMenuCreated();
popupMenu.add(c, index);
return c;
}
/**
* 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));
}
/**
* Creates a new menu item attached to the specified
* Action object and appends it to the end of this menu.
*
* @param a the Action for the menu item to be added
* @see Action
*/
public JMenuItem add(Action a) {
JMenuItem mi = createActionComponent(a);
mi.setAction(a);
add(mi);
return mi;
}
/**
* Factory method which creates the JMenuItem for
* Actions added to the JMenu.
*
* @param a the 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 PropertyChangeListener
* which updates the control as changes to the Action occur.
*/
protected PropertyChangeListener createActionChangeListener(JMenuItem b) {
return b.createActionPropertyChangeListener0(b.getAction());
}
/**
* Appends a new separator to the end of the menu.
*/
public void addSeparator()
{
ensurePopupMenuCreated();
popupMenu.addSeparator();
}
/**
* Inserts a new menu item with the specified text at a
* given position.
*
* @param s the text for the menu item to add
* @param pos an integer specifying the position at which to add the
* new menu item
* @exception IllegalArgumentException when the value of
* pos < 0
*/
public void insert(String s, int pos) {
if (pos < 0) {
throw new IllegalArgumentException("index less than zero.");
}
ensurePopupMenuCreated();
popupMenu.insert(new JMenuItem(s), pos);
}
/**
* Inserts the specified JMenuitem at a given position.
*
* @param mi the JMenuitem to add
* @param pos an integer specifying the position at which to add the
* new JMenuitem
* @return the new menu item
* @exception IllegalArgumentException if the value of
* pos < 0
*/
public JMenuItem insert(JMenuItem mi, int pos) {
if (pos < 0) {
throw new IllegalArgumentException("index less than zero.");
}
ensurePopupMenuCreated();
popupMenu.insert(mi, pos);
return mi;
}
/**
* Inserts a new menu item attached to the specified Action
* object at a given position.
*
* @param a the Action object for the menu item to add
* @param pos an integer specifying the position at which to add the
* new menu item
* @exception IllegalArgumentException if the value of
* pos < 0
*/
public JMenuItem insert(Action a, int pos) {
if (pos < 0) {
throw new IllegalArgumentException("index less than zero.");
}
ensurePopupMenuCreated();
JMenuItem mi = new JMenuItem(a);
mi.setHorizontalTextPosition(JButton.TRAILING);
mi.setVerticalTextPosition(JButton.CENTER);
popupMenu.insert(mi, pos);
return mi;
}
/**
* Inserts a separator at the specified position.
*
* @param index an integer specifying the position at which to
* insert the menu separator
* @exception IllegalArgumentException if the value of
* index < 0
*/
public void insertSeparator(int index) {
if (index < 0) {
throw new IllegalArgumentException("index less than zero.");
}
ensurePopupMenuCreated();
popupMenu.insert( new JPopupMenu.Separator(), index );
}
/**
* Returns the JMenuItem at the specified position.
* If the component at pos is not a menu item,
* null is returned.
* This method is included for AWT compatibility.
*
* @param pos an integer specifying the position
* @exception IllegalArgumentException if the value of
* pos < 0
* @return the menu item at the specified position; or null
* if the item as the specified position is not a menu item
*/
public JMenuItem getItem(int pos) {
if (pos < 0) {
throw new IllegalArgumentException("index less than zero.");
}
Component c = getMenuComponent(pos);
if (c instanceof JMenuItem) {
JMenuItem mi = (JMenuItem) c;
return mi;
}
// 4173633
return null;
}
/**
* Returns the number of items on the menu, including separators.
* This method is included for AWT compatibility.
*
* @return an integer equal to the number of items on the menu
* @see #getMenuComponentCount
*/
public int getItemCount() {
return getMenuComponentCount();
}
/**
* Returns true if the menu can be torn off. This method is not
* yet implemented.
*
* @return true if the menu can be torn off, else false
* @exception Error if invoked -- this method is not yet implemented
*/
public boolean isTearOff() {
throw new Error("boolean isTearOff() {} not yet implemented");
}
/**
* Removes the specified menu item from this menu. If there is no
* popup menu, this method will have no effect.
*
* @param item the JMenuItem to be removed from the menu
*/
public void remove(JMenuItem item) {
if (popupMenu != null)
popupMenu.remove(item);
}
/**
* Removes the menu item at the specified index from this menu.
*
* @param pos the position of the item to be removed
* @exception IllegalArgumentException if the value of
* pos < 0, or if pos
* is greater than the number of menu items
*/
public void remove(int pos) {
if (pos < 0) {
throw new IllegalArgumentException("index less than zero.");
}
if (pos > getItemCount()) {
throw new IllegalArgumentException("index greater than the number of items.");
}
if (popupMenu != null)
popupMenu.remove(pos);
}
/**
* Removes the component c from this menu.
*
* @param c the component to be removed
*/
public void remove(Component c) {
if (popupMenu != null)
popupMenu.remove(c);
}
/**
* Removes all menu items from this menu.
*/
public void removeAll() {
if (popupMenu != null)
popupMenu.removeAll();
}
/**
* Returns the number of components on the menu.
*
* @return an integer containing the number of components on the menu
*/
public int getMenuComponentCount() {
int componentCount = 0;
if (popupMenu != null)
componentCount = popupMenu.getComponentCount();
return componentCount;
}
/**
* Returns the component at position n.
*
* @param n the position of the component to be returned
* @return the component requested, or null
* if there is no popup menu
*
*/
public Component getMenuComponent(int n) {
if (popupMenu != null)
return popupMenu.getComponent(n);
return null;
}
/**
* Returns an array of Components of the menu's
* subcomponents. Note that this returns all Components
* in the popup menu, including separators.
*
* @return an array of Components or an empty array
* if there is no popup menu
*/
public Component[] getMenuComponents() {
if (popupMenu != null)
return popupMenu.getComponents();
return new Component[0];
}
/**
* Returns true if the menu is a 'top-level menu', that is, if it is
* the direct child of a menubar.
*
* @return true if the menu is activated from the menu bar;
* false if the menu is activated from a menu item
* on another menu
*/
public boolean isTopLevelMenu() {
return getParent() instanceof JMenuBar;
}
/**
* Returns true if the specified component exists in the
* submenu hierarchy.
*
* @param c the Component to be tested
* @return true if the Component exists, false otherwise
*/
public boolean isMenuComponent(Component c) {
// Are we in the MenuItem part of the menu
if (c == this)
return true;
// Are we in the PopupMenu?
if (c instanceof JPopupMenu) {
JPopupMenu comp = (JPopupMenu) c;
if (comp == this.getPopupMenu())
return true;
}
// Are we in a Component on the PopupMenu
int ncomponents = this.getMenuComponentCount();
Component[] component = this.getMenuComponents();
for (int i = 0 ; i < ncomponents ; i++) {
Component comp = component[i];
// Are we in the current component?
if (comp == c)
return true;
// Hmmm, what about Non-menu containers?
// Recursive call for the Menu case
if (comp instanceof JMenu) {
JMenu subMenu = (JMenu) comp;
if (subMenu.isMenuComponent(c))
return true;
}
}
return false;
}
/*
* Returns a point in the coordinate space of this menu's popupmenu
* which corresponds to the point p in the menu's
* coordinate space.
*
* @param p the point to be translated
* @return the point in the coordinate space of this menu's popupmenu
*/
private Point translateToPopupMenu(Point p) {
return translateToPopupMenu(p.x, p.y);
}
/*
* Returns a point in the coordinate space of this menu's popupmenu
* which corresponds to the point (x,y) in the menu's coordinate space.
*
* @param x the x coordinate of the point to be translated
* @param y the y coordinate of the point to be translated
* @return the point in the coordinate space of this menu's popupmenu
*/
private Point translateToPopupMenu(int x, int y) {
int newX;
int newY;
if (getParent() instanceof JPopupMenu) {
newX = x - getSize().width;
newY = y;
} else {
newX = x;
newY = y - getSize().height;
}
return new Point(newX, newY);
}
/**
* Returns the popupmenu associated with this menu. If there is
* no popupmenu, it will create one.
*/
public JPopupMenu getPopupMenu() {
ensurePopupMenuCreated();
return popupMenu;
}
/**
* Adds a listener for menu events.
*
* @param l the listener to be added
*/
public void addMenuListener(MenuListener l) {
listenerList.add(MenuListener.class, l);
}
/**
* Removes a listener for menu events.
*
* @param l the listener to be removed
*/
public void removeMenuListener(MenuListener l) {
listenerList.remove(MenuListener.class, l);
}
/**
* Returns an array of all the MenuListeners added
* to this JMenu with addMenuListener().
*
* @return all of the MenuListeners added or an empty
* array if no listeners have been added
* @since 1.4
*/
public MenuListener[] getMenuListeners() {
return listenerList.getListeners(MenuListener.class);
}
/**
* Notifies all listeners that have registered interest for
* notification on this event type. The event instance
* is created lazily.
*
* @exception Error if there is a null listener
* @see EventListenerList
*/
protected void fireMenuSelected() {
if (DEBUG) {
System.out.println("In JMenu.fireMenuSelected");
}
// Guaranteed to return a non-null array
Object[] listeners = listenerList.getListenerList();
// Process the listeners last to first, notifying
// those that are interested in this event
for (int i = listeners.length-2; i>=0; i-=2) {
if (listeners[i]==MenuListener.class) {
if (listeners[i+1]== null) {
throw new Error(getText() +" has a NULL Listener!! " + i);
} else {
// Lazily create the event:
if (menuEvent == null)
menuEvent = new MenuEvent(this);
((MenuListener)listeners[i+1]).menuSelected(menuEvent);
}
}
}
}
/**
* Notifies all listeners that have registered interest for
* notification on this event type. The event instance
* is created lazily.
*
* @exception Error if there is a null listener
* @see EventListenerList
*/
protected void fireMenuDeselected() {
if (DEBUG) {
System.out.println("In JMenu.fireMenuDeselected");
}
// Guaranteed to return a non-null array
Object[] listeners = listenerList.getListenerList();
// Process the listeners last to first, notifying
// those that are interested in this event
for (int i = listeners.length-2; i>=0; i-=2) {
if (listeners[i]==MenuListener.class) {
if (listeners[i+1]== null) {
throw new Error(getText() +" has a NULL Listener!! " + i);
} else {
// Lazily create the event:
if (menuEvent == null)
menuEvent = new MenuEvent(this);
((MenuListener)listeners[i+1]).menuDeselected(menuEvent);
}
}
}
}
/**
* Notifies all listeners that have registered interest for
* notification on this event type. The event instance
* is created lazily.
*
* @exception Error if there is a null listener
* @see EventListenerList
*/
protected void fireMenuCanceled() {
if (DEBUG) {
System.out.println("In JMenu.fireMenuCanceled");
}
// Guaranteed to return a non-null array
Object[] listeners = listenerList.getListenerList();
// Process the listeners last to first, notifying
// those that are interested in this event
for (int i = listeners.length-2; i>=0; i-=2) {
if (listeners[i]==MenuListener.class) {
if (listeners[i+1]== null) {
throw new Error(getText() +" has a NULL Listener!! "
+ i);
} else {
// Lazily create the event:
if (menuEvent == null)
menuEvent = new MenuEvent(this);
((MenuListener)listeners[i+1]).menuCanceled(menuEvent);
}
}
}
}
// Overriden to do nothing, JMenu doesn't support an accelerator
void configureAcceleratorFromAction(Action a) {
}
class MenuChangeListener implements ChangeListener, Serializable {
boolean isSelected = false;
public void stateChanged(ChangeEvent e) {
ButtonModel model = (ButtonModel) e.getSource();
boolean modelSelected = model.isSelected();
if (modelSelected != isSelected) {
if (modelSelected == true) {
fireMenuSelected();
} else {
fireMenuDeselected();
}
isSelected = modelSelected;
}
}
}
private ChangeListener createMenuChangeListener() {
return new MenuChangeListener();
}
/**
* Creates a window-closing listener for the popup.
*
* @param p the JPopupMenu
* @return the new window-closing listener
*
* @see WinListener
*/
protected WinListener createWinListener(JPopupMenu p) {
return new WinListener(p);
}
/**
* A listener class that watches for a popup window closing.
* When the popup is closing, the listener deselects the menu.
*
* 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 JavaBeansTM
* has been added to the
* 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 JavaBeansTM
* has been added to the java.beans package.
* Please see {@link java.beans.XMLEncoder}.
*/
protected class WinListener extends WindowAdapter implements Serializable {
JPopupMenu popupMenu;
/**
* Create the window listener for the specified popup.
* @since 1.4
*/
public WinListener(JPopupMenu p) {
this.popupMenu = p;
}
/**
* Deselect the menu when the popup is closed from outside.
*/
public void windowClosing(WindowEvent e) {
setSelected(false);
}
}
/**
* Messaged when the menubar selection changes to activate or
* deactivate this menu.
* Overrides JMenuItem.menuSelectionChanged.
*
* @param isIncluded true if this menu is active, false if
* it is not
*/
public void menuSelectionChanged(boolean isIncluded) {
if (DEBUG) {
System.out.println("In JMenu.menuSelectionChanged to " + isIncluded);
}
setSelected(isIncluded);
}
/**
* Returns an array of MenuElements containing the submenu
* for this menu component. If popup menu is null returns
* an empty array. This method is required to conform to the
* MenuElement interface. Note that since
* JSeparators do not conform to the MenuElement
* interface, this array will only contain JMenuItems.
*
* @return an array of MenuElement objects
*/
public MenuElement[] getSubElements() {
if(popupMenu == null)
return new MenuElement[0];
else {
MenuElement result[] = new MenuElement[1];
result[0] = popupMenu;
return result;
}
}
// implements javax.swing.MenuElement
/**
* Returns the java.awt.Component used to
* paint this MenuElement.
* The returned component is used to convert events and detect if
* an event is inside a menu component.
*/
public Component getComponent() {
return this;
}
/**
* Sets the ComponentOrientation property of this menu
* and all components contained within it. This includes all
* components returned by {@link #getMenuComponents getMenuComponents}.
*
* @param o the new component orientation of this menu and
* the components contained within it.
* @exception NullPointerException if orientation is null.
* @see java.awt.Component#setComponentOrientation
* @see java.awt.Component#getComponentOrientation
* @since 1.4
*/
public void applyComponentOrientation(ComponentOrientation o) {
super.applyComponentOrientation(o);
if ( popupMenu != null ) {
int ncomponents = getMenuComponentCount();
for (int i = 0 ; i < ncomponents ; ++i) {
getMenuComponent(i).applyComponentOrientation(o);
}
popupMenu.setComponentOrientation(o);
}
}
public void setComponentOrientation(ComponentOrientation o) {
super.setComponentOrientation(o);
if ( popupMenu != null ) {
popupMenu.setComponentOrientation(o);
}
}
/**
* setAccelerator is not defined for JMenu.
* Use setMnemonic instead.
* @param keyStroke the keystroke combination which will invoke
* the JMenuItem's actionlisteners
* without navigating the menu hierarchy
* @exception Error if invoked -- this method is not defined for JMenu.
* Use setMnemonic instead
*
* @beaninfo
* description: The keystroke combination which will invoke the JMenuItem's
* actionlisteners without navigating the menu hierarchy
* hidden: true
*/
public void setAccelerator(KeyStroke keyStroke) {
throw new Error("setAccelerator() is not defined for JMenu. Use setMnemonic() instead.");
}
/**
* 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);
}
/**
* Programmatically performs a "click". This overrides the method
* AbstractButton.doClick in order to make the menu pop up.
* @param pressTime indicates the number of milliseconds the
* button was pressed for
*/
public void doClick(int pressTime) {
MenuElement me[] = buildMenuElementArray(this);
MenuSelectionManager.defaultManager().setSelectedPath(me);
}
/*
* Build an array of menu elements - from PopupMenu to
* the root JMenuBar.
* @param leaf the leaf node from which to start building up the array
* @return the array of menu items
*/
private MenuElement[] buildMenuElementArray(JMenu leaf) {
VectorreadObject 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 JMenu. 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 null.
*
* @return a string representation of this JMenu.
*/
protected String paramString() {
return super.paramString();
}
/////////////////
// Accessibility support
////////////////
/**
* Gets the AccessibleContext associated with this JMenu.
* For JMenus, the AccessibleContext takes the form of an
* AccessibleJMenu.
* A new AccessibleJMenu instance is created if necessary.
*
* @return an AccessibleJMenu that serves as the
* AccessibleContext of this JMenu
*/
public AccessibleContext getAccessibleContext() {
if (accessibleContext == null) {
accessibleContext = new AccessibleJMenu();
}
return accessibleContext;
}
/**
* This class implements accessibility support for the
* JMenu class. It provides an implementation of the
* Java Accessibility API appropriate to menu user-interface elements.
* java.beans package.
* Please see {@link java.beans.XMLEncoder}.
*/
protected class AccessibleJMenu extends AccessibleJMenuItem
implements AccessibleSelection {
/**
* Returns the number of accessible children in the object. If all
* of the children of this object implement Accessible, than this
* method should return the number of children of this object.
*
* @return the number of accessible children in the object.
*/
public int getAccessibleChildrenCount() {
Component[] children = getMenuComponents();
int count = 0;
for (Component child : children) {
if (child instanceof Accessible) {
count++;
}
}
return count;
}
/**
* Returns the nth Accessible child of the object.
*
* @param i zero-based index of child
* @return the nth Accessible child of the object
*/
public Accessible getAccessibleChild(int i) {
Component[] children = getMenuComponents();
int count = 0;
for (Component child : children) {
if (child instanceof Accessible) {
if (count == i) {
if (child instanceof JComponent) {
// FIXME: [[[WDW - probably should set this when
// the component is added to the menu. I tried
// to do this in most cases, but the separators
// added by addSeparator are hard to get to.]]]
AccessibleContext ac = child.getAccessibleContext();
ac.setAccessibleParent(JMenu.this);
}
return (Accessible) child;
} else {
count++;
}
}
}
return null;
}
/**
* Get the role of this object.
*
* @return an instance of AccessibleRole describing the role of the
* object
* @see AccessibleRole
*/
public AccessibleRole getAccessibleRole() {
return AccessibleRole.MENU;
}
/**
* Get the AccessibleSelection associated with this object. In the
* implementation of the Java Accessibility API for this class,
* return this object, which is responsible for implementing the
* AccessibleSelection interface on behalf of itself.
*
* @return this object
*/
public AccessibleSelection getAccessibleSelection() {
return this;
}
/**
* Returns 1 if a sub-menu is currently selected in this menu.
*
* @return 1 if a menu is currently selected, else 0
*/
public int getAccessibleSelectionCount() {
MenuElement me[] =
MenuSelectionManager.defaultManager().getSelectedPath();
if (me != null) {
for (int i = 0; i < me.length; i++) {
if (me[i] == JMenu.this) { // this menu is selected
if (i+1 < me.length) {
return 1;
}
}
}
}
return 0;
}
/**
* Returns the currently selected sub-menu if one is selected,
* otherwise null (there can only be one selection, and it can
* only be a sub-menu, as otherwise menu items don't remain
* selected).
*/
public Accessible getAccessibleSelection(int i) {
// if i is a sub-menu & popped, return it
if (i < 0 || i >= getItemCount()) {
return null;
}
MenuElement me[] =
MenuSelectionManager.defaultManager().getSelectedPath();
if (me != null) {
for (int j = 0; j < me.length; j++) {
if (me[j] == JMenu.this) { // this menu is selected
// so find the next JMenuItem in the MenuElement
// array, and return it!
while (++j < me.length) {
if (me[j] instanceof JMenuItem) {
return (Accessible) me[j];
}
}
}
}
}
return null;
}
/**
* Returns true if the current child of this object is selected
* (that is, if this child is a popped-up submenu).
*
* @param i the zero-based index of the child in this Accessible
* object.
* @see AccessibleContext#getAccessibleChild
*/
public boolean isAccessibleChildSelected(int i) {
// if i is a sub-menu and is pop-ed up, return true, else false
MenuElement me[] =
MenuSelectionManager.defaultManager().getSelectedPath();
if (me != null) {
JMenuItem mi = JMenu.this.getItem(i);
for (int j = 0; j < me.length; j++) {
if (me[j] == mi) {
return true;
}
}
}
return false;
}
/**
* Selects the ith menu in the menu.
* If that item is a submenu,
* it will pop up in response. If a different item is already
* popped up, this will force it to close. If this is a sub-menu
* that is already popped up (selected), this method has no
* effect.
*
* @param i the index of the item to be selected
* @see #getAccessibleStateSet
*/
public void addAccessibleSelection(int i) {
if (i < 0 || i >= getItemCount()) {
return;
}
JMenuItem mi = getItem(i);
if (mi != null) {
if (mi instanceof JMenu) {
MenuElement me[] = buildMenuElementArray((JMenu) mi);
MenuSelectionManager.defaultManager().setSelectedPath(me);
} else {
MenuSelectionManager.defaultManager().setSelectedPath(null);
}
}
}
/**
* Removes the nth item from the selection. In general, menus
* can only have one item within them selected at a time
* (e.g. one sub-menu popped open).
*
* @param i the zero-based index of the selected item
*/
public void removeAccessibleSelection(int i) {
if (i < 0 || i >= getItemCount()) {
return;
}
JMenuItem mi = getItem(i);
if (mi != null && mi instanceof JMenu) {
if (mi.isSelected()) {
MenuElement old[] =
MenuSelectionManager.defaultManager().getSelectedPath();
MenuElement me[] = new MenuElement[old.length-2];
for (int j = 0; j < old.length -2; j++) {
me[j] = old[j];
}
MenuSelectionManager.defaultManager().setSelectedPath(me);
}
}
}
/**
* Clears the selection in the object, so that nothing in the
* object is selected. This will close any open sub-menu.
*/
public void clearAccessibleSelection() {
// if this menu is selected, reset selection to only go
// to this menu; else do nothing
MenuElement old[] =
MenuSelectionManager.defaultManager().getSelectedPath();
if (old != null) {
for (int j = 0; j < old.length; j++) {
if (old[j] == JMenu.this) { // menu is in the selection!
MenuElement me[] = new MenuElement[j+1];
System.arraycopy(old, 0, me, 0, j);
me[j] = JMenu.this.getPopupMenu();
MenuSelectionManager.defaultManager().setSelectedPath(me);
}
}
}
}
/**
* Normally causes every selected item in the object to be selected
* if the object supports multiple selections. This method
* makes no sense in a menu bar, and so does nothing.
*/
public void selectAllAccessibleSelection() {
}
} // inner class AccessibleJMenu
}