Module java.desktop
Package java.awt.event

Class FocusAdapter

java.lang.Object
java.awt.event.FocusAdapter
All Implemented Interfaces:
FocusListener, EventListener
Direct Known Subclasses:
BasicSplitPaneUI.FocusHandler, BasicTabbedPaneUI.FocusHandler
public abstract class FocusAdapter extends Object implements FocusListener
An abstract adapter class for receiving keyboard focus events. The methods in this class are empty. This class exists as convenience for creating listener objects.

Extend this class to create a FocusEvent listener and override the methods for the events of interest. (If you implement the FocusListener interface, you have to define all of the methods in it. This abstract class defines null methods for them all, so you can only have to define methods for events you care about.)

Create a listener object using the extended class and then register it with a component using the component's addFocusListener method. When the component gains or loses the keyboard focus, the relevant method in the listener object is invoked, and the FocusEvent is passed to it.

Since:
1.1
See Also:
FocusEvent, FocusListener, Tutorial: Writing a Focus Listener

  • Constructor Details

    • FocusAdapter

      protected FocusAdapter()
      Constructs a FocusAdapter.

  • Method Details

    • focusGained

      public void focusGained​(FocusEvent e)
      Invoked when a component gains the keyboard focus.
      Specified by:
      focusGained in interface FocusListener
      Parameters:
      e - the event to be processed

    • focusLost

      public void focusLost​(FocusEvent e)
      Invoked when a component loses the keyboard focus.
      Specified by:
      focusLost in interface FocusListener
      Parameters:
      e - the event to be processed