如何使用 Swift IOS 以编程方式创建布局和约束

Question

How do you programmatically create layout and constraints using Swift IOS. I'm familiar with storyboards, however I'm not sure how to use code to make ui elements.

Answer 1

There are three main steps. First you have to define the element, add it to the view, then add constraints.

For example,

let button = UIButton() 
button.translatesAutoresizingMaskIntoConstraints = false
view.addSubview(button) 

NSLayoutConstraint.activate([
        button.heightAnchor.constraint(equalTo: view.heightAnchor)
      
        
])