A FocusTraversalPolicy defines the order in which Components with a
particular focus cycle root are traversed in a Container.
The core responsibility of a FocusTraversalPolicy is to provide algorithms
determining the next and previous Components to focus when traversing
forward or backward in a UI. Each FocusTraversalPolicy must also provide
algorithms for determining the default Components in a
traversal cycle. The default Component is the first
to receive focus when traversing down into a new focus traversal cycle.
if the next/previous searched null to be returned, it means can't found a
component to be focused.
public function getComponentAfter(c:Component):Component
Returns the Component that should receive the focus after c.
Parameters
| c:Component — the focus position used to count next
|
Returns
| Component —
the Component that should receive the focus after c, or
null if no Component can be found in this policy
|
public function getComponentBefore(c:Component):Component
Returns the Component that should receive the focus before c.
Parameters
| c:Component — the focus position used to count previous
|
Returns
| Component —
the Component that should receive the focus before c, or
null if no Component can be found in this policy
|
public function getDefaultComponent(container:Container):Component
Returns the default Component to focus in the specifield container.
This Component will be the first to receive focus when traversing down into
this container.
Parameters
| container:Container — the cirle root container
|
Returns
| Component —
the default Component in the container,
or null if no Component can be found
|
