Flex SDK Wiki

class spark.accessibility.PanelAccImpl

This is the accessibility implementation class for spark.components.Panel. When a Spark Panel is created, the accessibilityImplementation property of its titleDisplay is set to an instance of this class. The Flash Player then uses this class to allow MSAA clients such as screen readers to see and manipulate the Panel. See the mx.accessibility.AccImpl and flash.accessibility.AccessibilityImplementation classes for background information about accessibility implementation classes and MSAA.

Children

A Panel has no MSAA children. All children of the actual Panel are siblings of the Panel in the FlashPlayer's MSAA tree, because Flash Player does not support objects with accessibility implementations having children with their own accessibility implementations.

The PanelAccImpl is set as the accessibilityImplementation of the titleDisplay object because setting it on the Panel itself would not allow the Panel's children to be exposed in MSAA. Because of this an invisible rectangle drawn in the titleDisplay making it the same size as the Panel as a whole so that the MSAA Location is the bounding rectangle of the entire Panel. Screen readers like JAWS rely on the accLocation to announce whether some component is in the grouping since the MSAA structure is flat.

Role

The MSAA Role of a Panel is ROLE_SYSTEM_GROUPING.

Name

The MSAA Name of a Panel is, by default, the title that it displays. To override this behavior, set the Panel's accessibilityName property.

When the Name changes, a Panel dispatches the MSAA event EVENT_OBJECT_NAMECHANGE.

Description

The MSAA Description of a Panel is, by default, the empty string, but you can set the Panel's accessibilityDescription property.

State

The MSAA State of a Panel is always STATE_SYSTEM_NORMAL, indicating that no state flags are set.

Since the state does not change, a Panel does not dispatch the MSAA event EVENT_OBJECT_STATECHANGE.

Value

The MSAA Value of a Panel is always the empty string.

Location

The MSAA Location of a Panel is its bounding rectangle.

Default Action

The MSAA DefaultAction of a Panel is the empty string.

Focus

A Panel does not accept focus.

Selection

A Panel does not support selection in the MSAA sense.