Auto Layout in Xcode 6 - Pinning view to edge of parent view creates -8 constraint

Question

In Xcode 6 when I try to pin an image view to the edge of UICollectionViewCell, auto-layout creates constraints of -8.0. What changed? I've tried to find release notes or documentation updates but haven't seen anything.

1. Notice the imageview is up against the edges of the collectionview cell

2. Frame X and Y are both zero

3. Adding constraints for leading space and trailing space to container margin results in a settings of -8.0

Why is this happening and what is the preferred approach for edge to edge content?

Answer 1

Before you add a new constraint, you will need to untick the "Constain to Margins". It is ticked by default.