I needed a completely transparent navigation bar for the mapView so I did this:
[self.navigationController.navigationBar setBackgroundImage:[UIImage new] forBarM
Set nil for image of navigation Controller on viewWillDisappear
on map view
Set this two method in your mapview
MapView.m
-(void)viewWillAppear:(BOOL)animated{
[self.navigationController.navigationBar setBackgroundImage:[UIImage new] forBarMetrics:UIBarMetricsDefault];
[self.navigationController.navigationBar setShadowImage:[UIImage new]];
}
-(void)viewWillDisappear:(BOOL)animated{
[self.navigationController.navigationBar setBackgroundImage:nil forBarMetrics:UIBarMetricsDefault];
[self.navigationController.navigationBar setShadowImage:nil];
}
For Swift 3:
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
self.navigationController?.navigationBar.setBackgroundImage(UIImage(), for: UIBarMetrics.default)
self.navigationController?.navigationBar.shadowImage = UIImage()
}
override func viewWillDisappear(_ animated: Bool) {
super.viewWillDisappear(animated)
self.navigationController?.navigationBar.setBackgroundImage(nil, for: UIBarMetrics.default)
self.navigationController?.navigationBar.shadowImage = nil
}
by the way, you get get the original background image by using function
UIImageView *imageView = [self.navigationController.navigationBar
backgroundImageForBarMetrics:UIBarMetricsDefault];
and store the image somewhere, then you use
[self.navigationController.navigationBar setBackgroundImage:imageView
forBarMetrics:UIBarMetricsDefault];
to set it back,but most time, set to nil will solve your problem.