How to control what subview comes on top in IB?

Suppose my view contains an image and a button. I'd like for the button to show up on top of the image? How can this be done as part of the Interface Builder?开发者_如何学运维

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In the xib file viewer, the view farthest down will be on top, the view highest up will be on the bottom. You can drag the views around to adjust their z-order.