| Notifies this content provider that the given viewer's input
has been switched to a different element.
A typical use for this method is registering the content provider as a listener
to changes on the new input (using model-specific means), and deregistering the viewer
from the old input. In response to these change notifications, the content provider
should update the viewer (see the add, remove, update and refresh methods on the viewers).
The viewer should not be updated during this call, as it might be in the process
of being disposed.
Parameters: viewer - the viewer Parameters: oldInput - the old input element, or null if the viewerdid not previously have an input Parameters: newInput - the new input element, or null if the viewerdoes not have an input |