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Java in a Nutshell

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The java.awt Package
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18.49 java.awt.PopupMenu (JDK 1.1)

PopupMenu is a simple subclass of Menu that represents a popup menu rather than a pulldown menu. You create a PopupMenu just as you would create a Menu object. The main difference is that a popup menu must be "popped up" in response to a user event by calling its show() method.

Another difference is that, unlike a Menu, which can only appear within a MenuBar or another Menu, a PopupMenu can be associated with any component in a graphical user interface. A PopupMenu is associated with a component by calling the add() method of the component.

Popup menus are popped up by the user in different ways on different platforms. In order to hide this platform-dependency, the MouseEvent class defines the isPopupTrigger() method. If this method returns true, the specified MouseEvent represents the platform-specific popup menu trigger event, and you should use the show() method to pop your PopupMenu up. Note that the X and Y coordinates passed to show() should be in the coordinate system of the specified Component.

public class PopupMenu extends Menu {
    // Public Constructors
            public PopupMenu();
            public PopupMenu(String label);
    // Public Instance Methods
            public synchronized void addNotify();  // Overrides Menu
            public void show(Component origin, int x, int y);
}

Hierarchy:

Object->MenuComponent(Serializable)->MenuItem->Menu(MenuContainer)->PopupMenu

Passed To:

Component.add(), Toolkit.createPopupMenu()


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