Class ContainerOrderFocusTraversalPolicy

• java.lang.Object
• • java.awt.FocusTraversalPolicy
  • • java.awt.ContainerOrderFocusTraversalPolicy

All Implemented Interfaces:

Serializable

Direct Known Subclasses:

DefaultFocusTraversalPolicy

public class ContainerOrderFocusTraversalPolicy
extends FocusTraversalPolicy
implements Serializable

Since:

1.4

See Also:

Container.getComponents(), Serialized Form

Constructors

ContainerOrderFocusTraversalPolicy

public ContainerOrderFocusTraversalPolicy()

Methods

getComponentAfter

public Component getComponentAfter(Container aContainer,
                                   Component aComponent)

Specified by:

getComponentAfter in class FocusTraversalPolicy

Parameters:

aContainer - a focus cycle root of aComponent or a 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 focus traversal policy provider, or if either aContainer or aComponent is null

getComponentBefore

public 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.

Specified by:

getComponentBefore in class FocusTraversalPolicy

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 focus traversal policy provider, or if either aContainer or aComponent is null

getFirstComponent

public 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.

Specified by:

getFirstComponent in class FocusTraversalPolicy

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 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.

Specified by:

getLastComponent in class FocusTraversalPolicy

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 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. The default implementation of this method returns the same Component as getFirstComponent.

Specified by:

getDefaultComponent in class FocusTraversalPolicy

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

See Also:

getFirstComponent(java.awt.Container)

setImplicitDownCycleTraversal

public void setImplicitDownCycleTraversal(boolean implicitDownCycleTraversal)

Sets whether this ContainerOrderFocusTraversalPolicy transfers focus down-cycle implicitly. If true, during normal forward focus traversal, the Component traversed after a focus cycle root will be the focus-cycle-root's default Component to focus. If false, the next Component in the focus traversal cycle rooted at the specified focus cycle root will be traversed instead. The default value for this property is true.

Parameters:

implicitDownCycleTraversal - whether this ContainerOrderFocusTraversalPolicy transfers focus down-cycle implicitly

See Also:

getImplicitDownCycleTraversal(), getFirstComponent(java.awt.Container)

getImplicitDownCycleTraversal

public boolean getImplicitDownCycleTraversal()

Returns whether this ContainerOrderFocusTraversalPolicy transfers focus down-cycle implicitly. If true, during normal forward focus traversal, the Component traversed after a focus cycle root will be the focus-cycle-root's default Component to focus. If false, the next Component in the focus traversal cycle rooted at the specified focus cycle root will be traversed instead.

Returns:

whether this ContainerOrderFocusTraversalPolicy transfers focus down-cycle implicitly

See Also:

setImplicitDownCycleTraversal(boolean), getFirstComponent(java.awt.Container)

accept

protected boolean accept(Component aComponent)

Determines whether a Component is an acceptable choice as the new focus owner. By default, this method will accept a Component if and only if it is visible, displayable, enabled, and focusable.

Parameters:

aComponent - the Component whose fitness as a focus owner is to be tested

Returns:

true if aComponent is visible, displayable, enabled, and focusable; false otherwise