Provides event-based control flow modeling. It behaves similarly to Switch in that it executes only one of several activities in response to events. It contains PickBranches with each branch having a Trigger and an Action. At the beginning of a Pick element's execution, all the trigger activities from all PickBranch elements are scheduled. When the first (leftmost) activity completes, the corresponding action activity is scheduled, and all other trigger activities are canceled.
In this example we have 3 branches, each branch having a delay activity as a trigger with 3, 2, 1 second(s) delay. Since the third one completes first(1 second delay), the third activity will be executed.