ios - Unable to simultaneously satisfy constraints Warnings with AVPlayerViewController embedded in storyboard

Question

I'm trying to set up an AVPlayerViewController completely through storyboards by embedding in a separate View Controller.

Steps:

1. Create Single View Application in Xcode.
2. Embed VC in navigation Controller.
3. Add toolbar at the bottom.(pinned to superView (Leading, Trailing, Bottom Layout Guide, Height(44)).
4. Add container View in parent View Controller.(pinned to superView (Leading, Trailing), Top Layout Guide, toolbar Top).
5. Remove the default View Controller that comes with container view.
6. Drag AV Player View Controller object from Object Library.
7. Connect embed segue from Container View to AV Player View Controller.

NO CODE ADDED.

This is what my storyboard looks like:

View hierarchy:

Everything runs fine: BUT THE PROBLEM IS: As soon as i run it I get these warnings in the debugger:

2015-09-30 12:58:35.904 AVPlayerTest[9352:446772] 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. (Note: If you're seeing NSAutoresizingMaskLayoutConstraints that you don't understand, refer to the documentation for the UIView property translatesAutoresizingMaskIntoConstraints) 
(
    "<NSAutoresizingMaskLayoutConstraint:0x7f93259513b0 h=-&- v=-&- _UIBackdropContentView:0x7f9325860000.width == _UIBackdropView:0x7f932585e990.width>",
    "<NSLayoutConstraint:0x7f932592bc70 H:|-(14)-[UILabel:0x7f9325925590'Hi-Speed Scrubbing']   (Names: '|':_UIBackdropContentView:0x7f9325860000 )>",
    "<NSLayoutConstraint:0x7f932592bcf0 H:[UILabel:0x7f9325925590'Hi-Speed Scrubbing']-(14)-|   (Names: '|':_UIBackdropContentView:0x7f9325860000 )>",
    "<NSLayoutConstraint:0x7f932592b770 H:|-(0)-[_UIBackdropView:0x7f932585e990]   (Names: '|':UIView:0x7f932585e830 )>",
    "<NSLayoutConstraint:0x7f932592b7f0 H:[_UIBackdropView:0x7f932585e990]-(0)-|   (Names: '|':UIView:0x7f932585e830 )>",
    "<NSLayoutConstraint:0x7f932592b450 H:|-(0)-[UIView:0x7f932585e830]   (Names: '|':AVAlphaUpdatingView:0x7f932585e310 )>",
    "<NSLayoutConstraint:0x7f932592b4d0 H:[UIView:0x7f932585e830]-(0)-|   (Names: '|':AVAlphaUpdatingView:0x7f932585e310 )>",
    "<NSLayoutConstraint:0x7f932594aa10 'UIView-Encapsulated-Layout-Width' H:[AVAlphaUpdatingView:0x7f932585e310(0)]>"
)

Will attempt to recover by breaking constraint 
<NSLayoutConstraint:0x7f932592bcf0 H:[UILabel:0x7f9325925590'Hi-Speed Scrubbing']-(14)-|   (Names: '|':_UIBackdropContentView:0x7f9325860000 )>

Make a symbolic breakpoint at UIViewAlertForUnsatisfiableConstraints to catch this in the debugger.
The methods in the UIConstraintBasedLayoutDebugging category on UIView listed in <UIKit/UIView.h> may also be helpful.
2015-09-30 12:58:35.905 AVPlayerTest[9352:446772] 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. (Note: If you're seeing NSAutoresizingMaskLayoutConstraints that you don't understand, refer to the documentation for the UIView property translatesAutoresizingMaskIntoConstraints) 
(
    "<NSAutoresizingMaskLayoutConstraint:0x7f93259513b0 h=-&- v=-&- _UIBackdropContentView:0x7f9325860000.width == _UIBackdropView:0x7f932585e990.width>",
    "<NSLayoutConstraint:0x7f932592bdd0 H:|-(14)-[UILabel:0x7f9325929bb0'Slide your finger up to a...']   (Names: '|':_UIBackdropContentView:0x7f9325860000 )>",
    "<NSLayoutConstraint:0x7f932592be50 H:[UILabel:0x7f9325929bb0'Slide your finger up to a...']-(14)-|   (Names: '|':_UIBackdropContentView:0x7f9325860000 )>",
    "<NSLayoutConstraint:0x7f932592b770 H:|-(0)-[_UIBackdropView:0x7f932585e990]   (Names: '|':UIView:0x7f932585e830 )>",
    "<NSLayoutConstraint:0x7f932592b7f0 H:[_UIBackdropView:0x7f932585e990]-(0)-|   (Names: '|':UIView:0x7f932585e830 )>",
    "<NSLayoutConstraint:0x7f932592b450 H:|-(0)-[UIView:0x7f932585e830]   (Names: '|':AVAlphaUpdatingView:0x7f932585e310 )>",
    "<NSLayoutConstraint:0x7f932592b4d0 H:[UIView:0x7f932585e830]-(0)-|   (Names: '|':AVAlphaUpdatingView:0x7f932585e310 )>",
    "<NSLayoutConstraint:0x7f932594aa10 'UIView-Encapsulated-Layout-Width' H:[AVAlphaUpdatingView:0x7f932585e310(0)]>"
)

Will attempt to recover by breaking constraint 
<NSLayoutConstraint:0x7f932592be50 H:[UILabel:0x7f9325929bb0'Slide your finger up to a...']-(14)-|   (Names: '|':_UIBackdropContentView:0x7f9325860000 )>

Make a symbolic breakpoint at UIViewAlertForUnsatisfiableConstraints to catch this in the debugger.
The methods in the UIConstraintBasedLayoutDebugging category on UIView listed in <UIKit/UIView.h> may also be helpful.
2015-09-30 12:58:35.906 AVPlayerTest[9352:446772] 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. (Note: If you're seeing NSAutoresizingMaskLayoutConstraints that you don't understand, refer to the documentation for the UIView property translatesAutoresizingMaskIntoConstraints) 
(
    "<NSLayoutConstraint:0x7f932592b5e0 V:|-(>=0)-[UIView:0x7f932585e830]   (Names: '|':AVAlphaUpdatingView:0x7f932585e310 )>",
    "<NSLayoutConstraint:0x7f932592b660 V:[UIView:0x7f932585e830]-(0)-|   (Names: '|':AVAlphaUpdatingView:0x7f932585e310 )>",
    "<NSLayoutConstraint:0x7f932592af50 V:[UIView:0x7f932585e830(44)]>",
    "<NSLayoutConstraint:0x7f9325952c30 'UIView-Encapsulated-Layout-Height' V:[AVAlphaUpdatingView:0x7f932585e310(0)]>"
)

Will attempt to recover by breaking constraint 
<NSLayoutConstraint:0x7f932592b660 V:[UIView:0x7f932585e830]-(0)-|   (Names: '|':AVAlphaUpdatingView:0x7f932585e310 )>

Make a symbolic breakpoint at UIViewAlertForUnsatisfiableConstraints to catch this in the debugger.
The methods in the UIConstraintBasedLayoutDebugging category on UIView listed in <UIKit/UIView.h> may also be helpful.
2015-09-30 12:58:35.907 AVPlayerTest[9352:446772] 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. (Note: If you're seeing NSAutoresizingMaskLayoutConstraints that you don't understand, refer to the documentation for the UIView property translatesAutoresizingMaskIntoConstraints) 
(
    "<NSAutoresizingMaskLayoutConstraint:0x7f93259513b0 h=-&- v=-&- _UIBackdropContentView:0x7f9325860000.width == _UIBackdropView:0x7f932585e990.width>",
    "<NSLayoutConstraint:0x7f932592ba00 H:|-(0)-[UIView:0x7f932585fbc0]   (Names: '|':_UIBackdropContentView:0x7f9325860000 )>",
    "<NSLayoutConstraint:0x7f932592ba80 H:[UIView:0x7f932585fbc0]-(0)-|   (Names: '|':_UIBackdropContentView:0x7f9325860000 )>",
    "<NSLayoutConstraint:0x7f932592b770 H:|-(0)-[_UIBackdropView:0x7f932585e990]   (Names: '|':UIView:0x7f932585e830 )>",
    "<NSLayoutConstraint:0x7f932592b7f0 H:[_UIBackdropView:0x7f932585e990]-(0)-|   (Names: '|':UIView:0x7f932585e830 )>",
    "<NSLayoutConstraint:0x7f932592b450 H:|-(0)-[UIView:0x7f932585e830]   (Names: '|':AVAlphaUpdatingView:0x7f932585e310 )>",
    "<NSLayoutConstraint:0x7f932592b4d0 H:[UIView:0x7f932585e830]-(0)-|   (Names: '|':AVAlphaUpdatingView:0x7f932585e310 )>",
    "<NSLayoutConstraint:0x7f932582a040 H:|-(14)-[AVButton:0x7f93258609b0](LTR)   (Names: '|':UIView:0x7f932585fbc0 )>",
    "<NSLayoutConstraint:0x7f9325829f90 H:[AVButton:0x7f93258609b0]-(15)-[UILabel:0x7f932347dc20'--:--'](LTR)>",
    "<NSLayoutConstraint:0x7f9325839550 H:[UILabel:0x7f932347dc20'--:--']-(12)-[AVScrubber:0x7f93234a4350](LTR)>",
    "<NSLayoutConstraint:0x7f932585a2f0 AVScrubber:0x7f93234a4350.right == UILabel:0x7f932583a470'--:--'.left - 12>",
    "<NSLayoutConstraint:0x7f932580b390 UILabel:0x7f932583a470'--:--'.right == AVButton:0x7f932585e480.left - 15>",
    "<NSLayoutConstraint:0x7f932586f490 AVButton:0x7f932585e480.right == AVButton:0x7f93234d1790.left - 10>",
    "<NSLayoutConstraint:0x7f932580b340 AVButton:0x7f93234d1790.right == AVButton:0x7f93234d6540.left - 10>",
    "<NSLayoutConstraint:0x7f932584c870 AVButton:0x7f93234d6540.right == UIView:0x7f932585fbc0.right - 14>",
    "<NSLayoutConstraint:0x7f932594aa10 'UIView-Encapsulated-Layout-Width' H:[AVAlphaUpdatingView:0x7f932585e310(0)]>"
)

Will attempt to recover by breaking constraint 
<NSLayoutConstraint:0x7f9325829f90 H:[AVButton:0x7f93258609b0]-(15)-[UILabel:0x7f932347dc20'--:--'](LTR)>

Make a symbolic breakpoint at UIViewAlertForUnsatisfiableConstraints to catch this in the debugger.
The methods in the UIConstraintBasedLayoutDebugging category on UIView listed in <UIKit/UIView.h> may also be helpful.
2015-09-30 12:58:35.909 AVPlayerTest[9352:446772] 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. (Note: If you're seeing NSAutoresizingMaskLayoutConstraints that you don't understand, refer to the documentation for the UIView property translatesAutoresizingMaskIntoConstraints) 
(
    "<NSAutoresizingMaskLayoutConstraint:0x7f93259513b0 h=-&- v=-&- _UIBackdropContentView:0x7f9325860000.width == _UIBackdropView:0x7f932585e990.width>",
    "<NSLayoutConstraint:0x7f932592ba00 H:|-(0)-[UIView:0x7f932585fbc0]   (Names: '|':_UIBackdropContentView:0x7f9325860000 )>",
    "<NSLayoutConstraint:0x7f932592ba80 H:[UIView:0x7f932585fbc0]-(0)-|   (Names: '|':_UIBackdropContentView:0x7f9325860000 )>",
    "<NSLayoutConstraint:0x7f932592b770 H:|-(0)-[_UIBackdropView:0x7f932585e990]   (Names: '|':UIView:0x7f932585e830 )>",
    "<NSLayoutConstraint:0x7f932592b7f0 H:[_UIBackdropView:0x7f932585e990]-(0)-|   (Names: '|':UIView:0x7f932585e830 )>",
    "<NSLayoutConstraint:0x7f932592b450 H:|-(0)-[UIView:0x7f932585e830]   (Names: '|':AVAlphaUpdatingView:0x7f932585e310 )>",
    "<NSLayoutConstraint:0x7f932592b4d0 H:[UIView:0x7f932585e830]-(0)-|   (Names: '|':AVAlphaUpdatingView:0x7f932585e310 )>",
    "<NSLayoutConstraint:0x7f932582a040 H:|-(14)-[AVButton:0x7f93258609b0](LTR)   (Names: '|':UIView:0x7f932585fbc0 )>",
    "<NSLayoutConstraint:0x7f932586f490 AVButton:0x7f932585e480.right == AVButton:0x7f93234d1790.left - 10>",
    "<NSLayoutConstraint:0x7f932580b340 AVButton:0x7f93234d1790.right == AVButton:0x7f93234d6540.left - 10>",
    "<NSLayoutConstraint:0x7f932584c870 AVButton:0x7f93234d6540.right == UIView:0x7f932585fbc0.right - 14>",
 

Answer 1

In fact, I think it's bug on Apple side.

I found a workaround : set showsPlaybackControls to YES after the AVPlayerViewController.player have been set.

I modify your sample with the following lines and no more Constraint error appears :

@interface ViewController ()

@property(weak, nonatomic) AVPlayerViewController * playerViewController;


@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];

    NSString *path = [[NSBundle mainBundle] pathForResource:@"test" ofType:@"mp4"];
    NSURL *url = [[NSURL alloc] initFileURLWithPath: path];
    AVPlayer * player = [AVPlayer playerWithURL:url];

    self.playerViewController.player = player;
    self.playerViewController.showsPlaybackControls = YES;
}


- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
    if ([segue.identifier isEqualToString:@"AVPlayerSegue"]) {
        self.playerViewController = segue.destinationViewController;
    }
}


@end

Please note that the file test.mp4 have been added to the project.