A base class for ref change request events
Cancels the operation, providing a message explaining why.
The cancellation message is required, and should be as descriptive and clear as possible to allow end
users to correct, if possible, the issue that triggered cancellation.
||a descriptive message explaining why the operation has been canceled
Retrieves a flag indicating whether the operation has been canceled.
In situations where multiple observers have the option to cancel an operation, for example when multiple
listeners receive the same
CancelableEvent, this flag
can be useful for determining that another observer has already canceled the operation.
true if the operation has been