IOS 7 vs iOS 8 Limitations vary in size
While working with auto layout and constraints in the interface builder, I noticed that I get different results with the same constraints when I run iOS7 vs iOS8 simulator.
For example, I have a very simple set of trailing limits on UIButton 8pts. These 8pts look very different in placement when running on iOS7 and iOS8. The iOS8 simulator seems to add several constraints to the constraint. It's as if there were functionality for Constraint Delta's ...
Any ideas why constraints behave differently in iOS7 and iOS8?
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The reason is that iOS 8 has layout boundaries, while iOS 7 does not. You made your constraints between the edge of the label and the supervisor mark, but there are no margins in iOS 7. Thus, to be compatible with both, the runtime must do something. So it treats fields as zero in iOS 7, which is what they are because they don't exist at all.
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