Module java.desktop
Package java.awt.event

Interface FocusListener

All Superinterfaces:
EventListener
All Known Implementing Classes:
AWTEventMulticaster, BasicButtonListener, BasicComboBoxEditor, BasicComboBoxEditor.UIResource, BasicComboBoxUI.FocusHandler, BasicListUI.FocusHandler, BasicSliderUI.FocusHandler, BasicSplitPaneUI.FocusHandler, BasicTabbedPaneUI.FocusHandler, BasicTableUI.FocusHandler, BasicTextUI.BasicCaret, BasicToolBarUI.ToolBarFocusListener, BasicTreeUI.FocusHandler, Component.AccessibleAWTComponent.AccessibleAWTFocusHandler, DefaultCaret, FocusAdapter, JComponent.AccessibleJComponent.AccessibleFocusHandler, MetalComboBoxEditor, MetalComboBoxEditor.UIResource
public interface FocusListener extends EventListener
The listener interface for receiving keyboard focus events on a component. The class that is interested in processing a focus event either implements this interface (and all the methods it contains) or extends the abstract FocusAdapter class (overriding only the methods of interest). The listener object created from that class is then registered 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:
FocusAdapter, FocusEvent, Tutorial: Writing a Focus Listener

  • 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.

  • Method Details

    • focusGained

      void focusGained​(FocusEvent e)
      Invoked when a component gains the keyboard focus.
      Parameters:
      e - the event to be processed

    • focusLost

      void focusLost​(FocusEvent e)
      Invoked when a component loses the keyboard focus.
      Parameters:
      e - the event to be processed