For an application I\'m developing, I need to display a custom back button in a navigation bar. I have the button asset as a PNG image, and I\'m writing this code:
As @pgb suggested you can use leftBarButtonItem instead of back button item. And to remove the default back button item set it to nil like follows;
navigationController?.navigationBar.backIndicatorImage = nil
navigationController?.navigationBar.backIndicatorTransitionMaskImage = nil
let button = UIButton.init(type: .custom)
button.imageView?.contentMode = UIViewContentMode.scaleAspectFit
button.setImage(UIImage.init(named: "top_back"), for: UIControlState.normal)
button.frame = CGRect.init(x: 0, y: 0, width: 75, height: 50)
button.addTarget(self, action: #selector(handleBackButton), for: .touchUpInside)
let barButton = UIBarButtonItem.init(customView: button)
self.navigationItem.leftBarButtonItem = barButton