iosios7navigationitem

Black bar appears under navigation bar

There are several similar questions which got no answers but were describe vaguely. I have reduced the problem into a very thin application, and added detailed screenshots. I would highly appreciate a solution for this!

The only involved code is one line added to viewDidLoad of the root VC. The purpose of this line is to make the navigation controller opaque:

- (void)viewDidLoad
{
    [super viewDidLoad];
    self.navigationController.navigationBar.translucent = NO;
}

A critical information for this question is that 'Title1' has a prompt in its navigation item, while 'Title2' has not prompt.

I have a storyboard with one navigation controller, one root VC called "Title1", with a segue button which takes to a second VC called "Title2"

storyboard

When pressing the button here:

pre press

I'm getting this strange screen:

after press

When pressing back (Title1), it gets worse (i.e.: the original label of Title1 was pushed up and now not being seen anymore!!!):

after back

Anyone please??

Solution

  • Late answer but I stumbled across this problem today and found your question and it doesn't have an accepted answer yet.

    I got this error while going from a prompted viewController to a non prompted viewController in storyboard.

    I got that black bar just like you.

    And to fix:

    // In prompted vc
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
    UIView.setAnimationsEnabled(false)
    self.navigationItem.prompt = nil
    UIView.setAnimationsEnabled(true)
}

    This will remove the prompt instantly before switching viewcontroller.

    UPDATE

    func prompt() -> String? {
    return nil
}

override func viewWillAppear(animated: Bool) {
    let action = { self.navigationItem.prompt = self.prompt() }
    
    if self.navigationController?.viewControllers.count <= 1 {
        UIView.performWithoutAnimation(action)
    }
    else {
        action()
    }
}

override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {        
    UIView.performWithoutAnimation {
        self.navigationItem.prompt = (segue.destinationViewController as? ViewController)?.prompt()
    }
}