UIBarButtonItem not working in ios11

Question

Long story short iOS10 left, right buttons, custom label working without issues, iOS11 none of the showing. I've read elsewhere that I need to add constraints for the buttons but that is not helping. Code called in viewDidLoad().

self.connectionButton = [[UIButton alloc] initWithFrame:CGRectMake(0.0,0.0,74.0,29.0)];
[self.connectionButton.widthAnchor constraintEqualToConstant:74].active = YES;
[self.connectionButton.heightAnchor constraintEqualToConstant:29].active = YES;
self.connectionButton.backgroundColor = [UIColor yellowColor];
UIBarButtonItem *buttonItem = [[UIBarButtonItem alloc] initWithCustomView:self.connectionButton];
self.navigationItem.rightBarButtonItem = buttonItem;

Appearance:

[[UINavigationBar appearance] setTranslucent:YES];
[[UINavigationBar appearance] setShadowImage:[UIImage new]];
[[UINavigationBar appearance] setBackgroundImage:[UIImage new] forBarPosition:UIBarPositionAny barMetrics:UIBarMetricsDefault];
[[UINavigationBar appearance] setBackgroundColor:[UIColor clearColor]];

When I check the frame during run time it's correct (0,0,74,29). No button is shown in the bar though.

XCode 9 beta 8, not working on either device nor simulator.

Answer 1

With more testing I found out that the navigation bar doesn't show anything - not even the title in default appearance. After hours wasted on commenting/uncommenting pieces of unrelated code I found the culprit:

    override var traitCollection: UITraitCollection {  
        var horizTraitCollection = UITraitCollection(horizontalSizeClass: .regular)  
        if view.bounds.width < view.bounds.height {  
            horizTraitCollection = UITraitCollection(horizontalSizeClass: .compact)  
        }

        return UITraitCollection(traitsFrom: [horizTraitCollection, UITraitCollection(verticalSizeClass: super.traitCollection.verticalSizeClass)])
     }

This is what I use override size class for portrait/landscape presentation. IMO completely unrelated to navigation bar appearance. No idea why is it breaking the navigation bar or how to fix it .

EDIT: After some tweaking I was able to get it working on iPads but not iPhones. After some more tweaking I got it working on iPhone as well:

override var traitCollection: UITraitCollection {  
    if UIDevice.current.userInterfaceIdiom == .pad {  
        var horizTraitCollection = UITraitCollection(horizontalSizeClass: .regular)  
        if UIDevice.current.orientation.isPortrait {  
            horizTraitCollection = UITraitCollection(horizontalSizeClass: .compact)  
        }  
        return UITraitCollection(traitsFrom: [horizTraitCollection, UITraitCollection(verticalSizeClass: super.traitCollection.verticalSizeClass)])  
    }  
    return super.traitCollection  
}