Debugging Constraints

You have added constraints to BNRDetailViewController.xib that will allow Auto Layout to determine alignment rectangles for every view in the hierarchy and give you the layout that you want on the iPhone and the iPad. Given the sheer number of constraints, it is easy to introduce problems. You can miss a constraint, you could have constraints that conflict, or you could have a constraint that conflicts with how a view appears on the canvas.

Fortunately, there are several tools you can use to debug Auto Layout constraints. Let’s take a look at each of these in turn and see ways to fix them.

Ambiguous layout

An ambiguous layout occurs when there is more then one way to fulfill a set of constraints. ...

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