Based on a ton of observation I believe (but cannot know for certain) that the constraints named UIView-Encapsulated-Layout-Width
and UIView-Encapsulated-Layout-Height
are created by UICollectionView
and friends, and exist to enforce the size returned by the sizeForItemAtIndexPath
delegate method. I guess it's there to ensure that the UICollectionViewCell
set up by cellForItemAtIndexPath
ends up the size that it was told it would be.
Which answers my initial question here. A second question is why were the constraints unsatisfiable? The cell's intrinsic height should have been the same as UIView-Encapsulated-Layout-Height
. Again, I don't know for certain, but I suspect it was a rounding error (i.e. intrinsic height came to 200.1 pixels, the UIView-Encapsulated-Layout-Height
maybe rounded to 200. The fix I came up with was to just lower the priority of the relevant cell constraint to allow UIView-Encapsulated-Layout-Height
to have the last word.