iOS模拟器：“空白应用”无法同时满足约束

Question

1. Create new single-view application (no other editing).
2. Build and launch to an iPhone in the Simulator.
3. Toggle in-call status bar.
4. "Unable to simultaneously satisfy constraints"

This is with Xcode 7.2, Simulator 9.2, iOS 9.2, OS X 10.11.2.

Was getting the constrains error in our project for no reason, and pared things back to the beginning. Now what when there's no custom content, just the default blank view controller??

Testing on real devices only and hoping for the best doesn't seem like a good solution...

Answer 1

Indeed it shows an error log but if you check the conflicting views they seem to be private ( UIInputSetContainerView , UITextEffectsWindow ) which might be an indication of an Apple bug.

2016-01-14 14:45:22.765 Teste[17945:2314568] Unable to simultaneously satisfy constraints.
    Probably at least one of the constraints in the following list is one you don't want. 
    Try this: 
        (1) look at each constraint and try to figure out which you don't expect; 
        (2) find the code that added the unwanted constraint or constraints and fix it. 
(
    "<NSLayoutConstraint:0x7fee78e27a00 V:|-(20)-[UIInputSetContainerView:0x7fee78e25000]   (Names: '|':UITextEffectsWindow:0x7fee78e20330 )>",
    "<NSLayoutConstraint:0x7fee78c90e30 'UIInputWindowController-top' V:|-(0)-[UIInputSetContainerView:0x7fee78e25000]   (Names: '|':UITextEffectsWindow:0x7fee78e20330 )>"
)

Will attempt to recover by breaking constraint 
<NSLayoutConstraint:0x7fee78e27a00 V:|-(20)-[UIInputSetContainerView:0x7fee78e25000]   (Names: '|':UITextEffectsWindow:0x7fee78e20330 )>

I found the same issue being reported on Apple Developer Forums .

I think if you don't actually see anything breaking you can safely disregard it. I hope that helps.