src/share/classes/java/awt/event/FocusListener.java

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  25 
  26 package java.awt.event;
  27 
  28 import java.util.EventListener;
  29 
  30 /**
  31  * The listener interface for receiving keyboard focus events on
  32  * a component.
  33  * The class that is interested in processing a focus event
  34  * either implements this interface (and all the methods it
  35  * contains) or extends the abstract <code>FocusAdapter</code> class
  36  * (overriding only the methods of interest).
  37  * The listener object created from that class is then registered with a
  38  * component using the component's <code>addFocusListener</code>
  39  * method. When the component gains or loses the keyboard focus,
  40  * the relevant method in the listener object
  41  * is invoked, and the <code>FocusEvent</code> is passed to it.
  42  *
  43  * @see FocusAdapter
  44  * @see FocusEvent
  45  * @see <a href="http://docs.oracle.com/javase/tutorial/uiswing/events/focuslistener.html">Tutorial: Writing a Focus Listener</a>
  46  *
  47  * @author Carl Quinn
  48  * @since 1.1
  49  */
  50 public interface FocusListener extends EventListener {
  51 
  52     /**
  53      * Invoked when a component gains the keyboard focus.
  54      */
  55     public void focusGained(FocusEvent e);
  56 
  57     /**
  58      * Invoked when a component loses the keyboard focus.
  59      */
  60     public void focusLost(FocusEvent e);
  61 }


  25 
  26 package java.awt.event;
  27 
  28 import java.util.EventListener;
  29 
  30 /**
  31  * The listener interface for receiving keyboard focus events on
  32  * a component.
  33  * The class that is interested in processing a focus event
  34  * either implements this interface (and all the methods it
  35  * contains) or extends the abstract <code>FocusAdapter</code> class
  36  * (overriding only the methods of interest).
  37  * The listener object created from that class is then registered with a
  38  * component using the component's <code>addFocusListener</code>
  39  * method. When the component gains or loses the keyboard focus,
  40  * the relevant method in the listener object
  41  * is invoked, and the <code>FocusEvent</code> is passed to it.
  42  *
  43  * @see FocusAdapter
  44  * @see FocusEvent
  45  * @see <a href="https://docs.oracle.com/javase/tutorial/uiswing/events/focuslistener.html">Tutorial: Writing a Focus Listener</a>
  46  *
  47  * @author Carl Quinn
  48  * @since 1.1
  49  */
  50 public interface FocusListener extends EventListener {
  51 
  52     /**
  53      * Invoked when a component gains the keyboard focus.
  54      */
  55     public void focusGained(FocusEvent e);
  56 
  57     /**
  58      * Invoked when a component loses the keyboard focus.
  59      */
  60     public void focusLost(FocusEvent e);
  61 }