Bottom bar added with interface builder doesn't display
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I wont to add a bottom toolbar to an iPad view. Although I add it with interface builder...

![enter image description here][1]

![enter image description here][2]

... I can't visualize it in my app. The only way to add a bar to the bottom is by dragging a toolbar from the library. Could you explain me why ?

thanks


  [1]: http://i.stack.imgur.com/XfaTe.png
  [2]: http://i.stack.imgur.com/Ys6gU.png