Receiving Errors for IAccessible Interface Pointers

This topic describes situations in which you might receive an error for an IAccessible interface pointer. IAccessible functions can return errors for IAccessible interface pointers when a user closes an application that the object belongs to, or if a user dismisses a control through the user interface.

User Closes an Application

If a user closes the application that contains an object to which the IAccessible interface pointer was pointing, then all future calls to that object will return an error code. The error, such as CO_E_OBJNOTCONNECTED, will indicate that the object does not exist anymore. This applies to all IAccessible interface pointers.

User Dismisses a Control

If a user dismisses a control (for example, by pressing a push button), clients can still call IAccessible methods and properties on this object because the object has not been released. However, future calls will receive error messages.

This situation applies to the following functions and methods:

• AccessibleObjectFromEvent
• AccessibleObjectFromPoint
• AccessibleObjectFromWindow
• IAccessible::accHitTest
• IAccessible::accNavigate
• IAccessible::get_accFocus
• IAccessible::get_accSelection