2 Replies
Walt Hamilton

Right Click the object, and choose Bring to Front, or Send to Back

In the home tab, select the Arrange icon, and choose Bring to Front, or Send to Back

Or, the coolest way of all, drag the object up or down in the timeline pane. Their order in this pane represents the Z position or all the objects.

Doing it dynamically while it is running requires smoke and mirrors, and a lot of work. You could probably do it by changing one object to a Hidden state, and another to a Normal state.