title: Xcode 4 and Interface Builder: Editing Vertical Spacing Constraint (Anchor Top, not Bottom)
body: <p>I've got a widget that is not laying out correctly on device (its <em>looks</em> OK in IB, but its not quite right). The widget is a label and its located about mid-screen. Interface Builder gave it a Vertical Space Constraint with a 'Bottom Anchor'. Here, bottom means bottom of the screen (rather than a widget below, or anchor to top screen).</p>
  
  <p>I'm in the inspector, but I don't see how to change to a top anchor (preferably, to the widget above). I tried reading Apple's <a href="http://developer.apple.com/library/ios/#recipes/xcode_help-interface_builder/articles/UnderstandingAutolayout.html" rel="noreferrer">docs</a> and <a href="http://developer.apple.com/library/ios/#recipes/xcode_help-interface_builder/articles/AutolayoutEditing.html" rel="noreferrer">Editing Constraints</a> in particular, but it was a confusing and did not explain how to make the change (or I missed the discussion - which was 7 sentences).</p>
  
  <p>Below is a screen capture under Interface Builder showing the Vertical Space Constraint anchored to the bottom of the screen. And its attributes leave a lot to be desired - Equal, Constant and Priority don't really help.</p>
  
  <p><img src="https://i.stack.imgur.com/enSWx.png" alt="enter image description here"></p>
  
  <p>Does anyone know how to edit constraints? Specifically, I want to (1) change a vertical spacer's anchor from bottom <em>to</em> top; and (2) anchor against the widget above, and not the top of the screen.</p>