I use User tasks in my process models.
In some of these, I care to know when the user starts working on the task.
(note the difference of the moment of instantiation of a User task and the moment that the user starts to perform the actual work, i.e., putting a task item on someone’s task inbox, doesn’t mean that the task started as the operator might start working on it later).
How shall I model it?
One option might be to have a form field (e.g. checkbox) or a button in a task form, where the user can indicate that he will start working on the task. But what if this indication shall trigger some other action? How can I trigger a message from a form? Should I use an non-interrupting message boundary event?
Another option is to have an event subprocess to catch such action and then take action. But in that case I will miss the visual connection with the user task.