@Rui Wang
Thanks, but I know that. I'm triggering already the process based on activity. I need to use the activity data inside the macro in the conditional block in the process.
I've found some solution for that. Kentico fills these special fields which can be used in the macro:
AutomationState.StateCustomData["TriggerDataActivityItemDetailId"]
AutomationState.StateCustomData["TriggerDataActivityItemId"]
AutomationState.StateCustomData["TriggerDataActivityValue"]
AutomationState.StateCustomData["TriggerDataActivitySiteId"]