If you have a UIViewController
in a UINavigationController
you can set the left and the right bar button of the view controller with
// System item
self.navigationItem.leftBarButtonItem = UIBarButtonItem(barButtonSystemItem: .action, target: self, action: #selector(action))
self.navigationItem.rightBarButtonItem = UIBarButtonItem(barButtonSystemItem: .action, target: self, action: #selector(action))
// Tittle
self.navigationItem.leftBarButtonItem = UIBarButtonItem(title: "Left Button", style: .plain, target: self, action: #selector(action))
self.navigationItem.rightBarButtonItem = UIBarButtonItem(title: "Right Button", style: .plain, target: self, action: #selector(action))
// Image
self.navigationItem.leftBarButtonItem = UIBarButtonItem(image: image, style: .plain, target: self, action: #selector(action))
self.navigationItem.rightBarButtonItem = UIBarButtonItem(image: image, style: .plain, target: self, action: #selector(action))
// Custom view
self.navigationItem.leftBarButtonItem = UIBarButtonItem(customView: view)
self.navigationItem.rightBarButtonItem = UIBarButtonItem(customView: view)