How a view breaks its agreement with update in a state:
Rejected: it sends a message that update rejects, so the control that sends it does nothing: a button
shown in the wrong state, or a value typed that update does not store;
ActsTwice: a message it sends acts again when sent twice from the same frame (a double tap), so a one-shot
action would happen twice;
Missing: update accepts a message that it does not send: a control missing from the screen.
How a view breaks its agreement with
updatein a state:Rejected: it sends a message thatupdaterejects, so the control that sends it does nothing: a button shown in the wrong state, or a value typed thatupdatedoes not store;ActsTwice: a message it sends acts again when sent twice from the same frame (a double tap), so a one-shot action would happen twice;Missing:updateaccepts a message that it does not send: a control missing from the screen.