I have added a navigation bar to the top of a view controller. I am trying to control whether a button is visible based a condition, but I am having trouble adding the butto
It’s simple. Put this line of code to the viewDidLoad:
self.navigationItem.rightBarButtonItem = UIBarButtonItem(title: "test", style: .done, target: self, action: #selector(addTapped))
Updated for Swift 4 or later:
A custom function:
@objc func action(sender: UIBarButtonItem) {
// Function body goes here
}
(Custom) Right bar button item:
self.navigationItem.rightBarButtonItem = UIBarButtonItem.init(title: "some_text", style: .done, target: self, action: #selector(self.action(sender:)))
(Custom) Left bar button item:
self.navigationItem.leftBarButtonItem = UIBarButtonItem.init(title: "some_text", style: .done, target: self, action: #selector(self.action(sender:)))
Also you can add a system bar button items something like this: UIBarButtonItem.SystemItem Defines system-supplied images for bar button items: .add, .done, .cancel, .edit, .save, .compose, .reply, .organize and more.
(System) Right bar button item:
self.navigationItem.rightBarButtonItem = UIBarButtonItem.init(barButtonSystemItem: UIBarButtonItem.SystemItem.add, target: self, action: #selector(self.action(sender:)))
(System) Left bar button item:
self.navigationItem.leftBarButtonItem = UIBarButtonItem.init(barButtonSystemItem: UIBarButtonItem.SystemItem.add, target: self, action: #selector(self.action(sender:)))