Current view
Hi,
commandData.Application.ActiveUIDocument.ActiveView = myLevel1View;
The complicated task is to find myLevel1View.
You have to find a ViewPlan whose GenLevel.Id matches your Level1.Id.
Also, this ViewPlan must be of ViewType.FloorPlan since there are also ViewPlans for ceilings and area plans.
In fact, there could still be several cadidate ViewPlans matching these conditions, perhaps just different by scale, detail level, display style etc.
It depends on yourself which one to use.
Revitalizer