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Java in a Nutshell

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The java.awt.event Package
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20.12 java.awt.event.FocusEvent (JDK 1.1)

An event of this type indicates that a Component has gained or lost focus on a temporary or permanent basis.

Use the inherited getComponent() method to determine which component has gained or lost focus. Use getID() to determine the type of focus event; it returns FOCUS_GAINED or FOCUS_LOST.

When focus is lost, you can call isTemporary() to determine whether it is a temporary loss of focus. Temporary focus loss occurs when the window that contains the component loses focus, for example, or when focus is temporarily diverted to a popup menu or a scrollbar. Similarly, you can also use isTemporary() to determine whether focus is being granted to a component on a temporary basis.

public class FocusEvent extends ComponentEvent {
    // Public Constructors
            public FocusEvent(Component source, int id, boolean temporary);
            public FocusEvent(Component source, int id);
    // Constants
            public static final int FOCUS_FIRST;
            public static final int FOCUS_GAINED;
            public static final int FOCUS_LAST;
            public static final int FOCUS_LOST;
    // Public Instance Methods
            public boolean isTemporary();
            public String paramString();  // Overrides ComponentEvent
}

Hierarchy:

Object->EventObject(Serializable)->AWTEvent->ComponentEvent->FocusEvent

Passed To:

AWTEventMulticaster.focusGained(), AWTEventMulticaster.focusLost(), Component.processFocusEvent(), FocusAdapter.focusGained(), FocusAdapter.focusLost(), FocusListener.focusGained(), FocusListener.focusLost()


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