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:

  • Constructor Summary

    Constructors
    Modifier
    Constructor
    Description
    protected
    FocusAdapter()
    Constructs a FocusAdapter.

  • Method Summary

    Modifier and Type
    Method
    Description
    void
    focusGained(FocusEvent e)
    Invoked when a component gains the keyboard focus.
    void
    focusLost(FocusEvent e)
    Invoked when a component loses the keyboard focus.

    Methods declared in class Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
    Modifier and Type
    Method
    Description
    protected Object
    clone()
    Creates and returns a copy of this object.
    boolean
    equals(Object obj)
    Indicates whether some other object is "equal to" this one.
    protected void
    finalize()
    Deprecated, for removal: This API element is subject to removal in a future version.
    Finalization is deprecated and subject to removal in a future release.
    final Class<?>
    getClass()
    Returns the runtime class of this Object.
    int
    hashCode()
    Returns a hash code value for this object.
    final void
    notify()
    Wakes up a single thread that is waiting on this object's monitor.
    final void
    notifyAll()
    Wakes up all threads that are waiting on this object's monitor.
    String
    toString()
    Returns a string representation of the object.
    final void
    wait()
    Causes the current thread to wait until it is awakened, typically by being notified or interrupted.
    final void
    wait(long timeoutMillis)
    Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.
    final void
    wait(long timeoutMillis, int nanos)
    Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

  • 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