State Initialization Activity
The State Initialization Activity is a sequence activity that contains child activities. When the State machine transitions to a state, the children inside the initialization activity will execute. We can only have one initialization activity per state. Once we have dropped this activity inside a state, we can double-click to edit the children.
The StateInitializationActivity functions much like a typical SequenceActivity, except that it is used as the first activity in a state in a StateMachineWorkflowActivity.
You have an ability to simply drag and drop the StateInitializationActivity within any State Activity of the Workflow as displayed below.