以编程方式将系统图像添加到导航栏

Question

I'm trying to move from storyboards to coding programmatically. I'm trying to add a barbuttonitem to my navigation bar. However, I don't want to use my own images, I want to use the default system images, such as "magnifyingglass.circle".

Here is my code:

let button = UIBarButtonItem.init(image: UIImage(contentsOfFile: "magnifyingglass.circle") , style: .plain, target: nil, action: nil)
navigationItem.leftBarButtonItem = button

However, nothing is added to my navigation bar.

Answer 1

You are using the wrong UIImage initializer. The one you are trying to use requires a full path to an image file. You want UIImage(systemName:) .

let button = UIBarButtonItem(image: UIImage(systemName: "magnifyingglass.circle") , style: .plain, target: nil, action: nil)