Class FocusTraversalPolicy

Constructor Detail

• FocusTraversalPolicy

  public FocusTraversalPolicy()

Method Detail

• getComponentAfter

  public abstract Component getComponentAfter(Container aContainer,
                            Component aComponent)

  Returns the Component that should receive the focus after aComponent. aContainer must be a focus cycle root of aComponent or a focus traversal policy provider.

  Parameters:

  aContainer - a focus cycle root of aComponent or focus traversal policy provider

  aComponent - a (possibly indirect) child of aContainer, or aContainer itself

  Returns:

  the Component that should receive the focus after aComponent, or null if no suitable Component can be found

  Throws:

  IllegalArgumentException - if aContainer is not a focus cycle root of aComponent or a focus traversal policy provider, or if either aContainer or aComponent is null

• getComponentBefore

  public abstract Component getComponentBefore(Container aContainer,
                             Component aComponent)

  Returns the Component that should receive the focus before aComponent. aContainer must be a focus cycle root of aComponent or a focus traversal policy provider.

  Parameters:

  aContainer - a focus cycle root of aComponent or focus traversal policy provider

  aComponent - a (possibly indirect) child of aContainer, or aContainer itself

  Returns:

  the Component that should receive the focus before aComponent, or null if no suitable Component can be found

  Throws:

  IllegalArgumentException - if aContainer is not a focus cycle root of aComponent or a focus traversal policy provider, or if either aContainer or aComponent is null

• getFirstComponent

  public abstract Component getFirstComponent(Container aContainer)

  Returns the first Component in the traversal cycle. This method is used to determine the next Component to focus when traversal wraps in the forward direction.

  Parameters:

  aContainer - the focus cycle root or focus traversal policy provider whose first Component is to be returned

  Returns:

  the first Component in the traversal cycle of aContainer, or null if no suitable Component can be found

  Throws:

  IllegalArgumentException - if aContainer is null

• getLastComponent

  public abstract Component getLastComponent(Container aContainer)

  Returns the last Component in the traversal cycle. This method is used to determine the next Component to focus when traversal wraps in the reverse direction.

  Parameters:

  aContainer - the focus cycle root or focus traversal policy provider whose last Component is to be returned

  Returns:

  the last Component in the traversal cycle of aContainer, or null if no suitable Component can be found

  Throws:

  IllegalArgumentException - if aContainer is null

• getDefaultComponent

  public abstract Component getDefaultComponent(Container aContainer)

  Returns the default Component to focus. This Component will be the first to receive focus when traversing down into a new focus traversal cycle rooted at aContainer.

  Parameters:

  aContainer - the focus cycle root or focus traversal policy provider whose default Component is to be returned

  Returns:

  the default Component in the traversal cycle of aContainer, or null if no suitable Component can be found

  Throws:

  IllegalArgumentException - if aContainer is null

• getInitialComponent

  public Component getInitialComponent(Window window)

  Returns the Component that should receive the focus when a Window is made visible for the first time. Once the Window has been made visible by a call to show() or setVisible(true), the initial Component will not be used again. Instead, if the Window loses and subsequently regains focus, or is made invisible or undisplayable and subsequently made visible and displayable, the Window's most recently focused Component will become the focus owner. The default implementation of this method returns the default Component.

  Parameters:

  window - the Window whose initial Component is to be returned

  Returns:

  the Component that should receive the focus when window is made visible for the first time, or null if no suitable Component can be found

  Throws:

  IllegalArgumentException - if window is null

  See Also:

  getDefaultComponent(java.awt.Container), Window.getMostRecentFocusOwner()