how to make three views the same size and resized depending on the container view? - ios

Question

I have three views on the bottom of the view. I'm trying to make them have the same size and the size can be resized automatically depending on the size of the container view. I'd like to do it programmatically.
Here's how I want them to look
Here's how it looks by my current code
import UIKit
class ViewController: UIViewController {
var view1 = UIView(frame: CGRect(x: 100, y: 100, width: 100, height: 100))
var view2 = UIView(frame: CGRect(x: 300, y: 300, width: 50, height: 50))
var view3 = UIView(frame: CGRect(x: 400, y: 500, width: 70, height: 70))
override func viewDidLoad() {
super.viewDidLoad()
view.addSubview(view1)
view.addSubview(view2)
view.addSubview(view3)
view1.backgroundColor = .orange
view2.backgroundColor = .black
view3.backgroundColor = .gray
view1.translatesAutoresizingMaskIntoConstraints = false
view2.translatesAutoresizingMaskIntoConstraints = false
view3.translatesAutoresizingMaskIntoConstraints = false
// view1.topAnchor.constraint(equalTo: view.topAnchor, constant: 10).isActive = true
view1.bottomAnchor.constraint(equalTo: view.bottomAnchor, constant: -10).isActive = true
view1.leadingAnchor.constraint(equalTo: view.leadingAnchor, constant: -10).isActive = true
view1.widthAnchor.constraint(equalTo: view.widthAnchor, constant: view.frame.size.width*0.01).isActive = true
view2.heightAnchor.constraint(equalToConstant: view.frame.size.height*0.1).isActive = true
//view2.topAnchor.constraint(equalTo: view.topAnchor, constant: 10).isActive = true
view2.bottomAnchor.constraint(equalTo: view.bottomAnchor, constant: -10).isActive = true
view2.leadingAnchor.constraint(equalTo: view1.leadingAnchor, constant: view.frame.size.width*(2/3)).isActive = true
view2.widthAnchor.constraint(equalTo: view1.widthAnchor, constant: 0).isActive = true
view2.heightAnchor.constraint(equalTo: view1.heightAnchor, constant: 0).isActive = true
// view3.topAnchor.constraint(equalTo: view.topAnchor, constant: 10).isActive = true
view3.bottomAnchor.constraint(equalTo: view.bottomAnchor, constant: -10).isActive = true
view3.leadingAnchor.constraint(equalTo: view2.leadingAnchor, constant: 10).isActive = true
view3.widthAnchor.constraint(equalTo: view2.widthAnchor, constant: 0).isActive = true
view3.heightAnchor.constraint(equalTo: view2.heightAnchor, constant: 0).isActive = true
}
}

Answer 1

Here, you can use the concept of UIStackView. Here, you can get your desired output using the following code(sample demo)
import UIKit
class ViewController: UIViewController {
var view1 = UIView()
var view2 = UIView()
var view3 = UIView()
override func viewDidLoad() {
super.viewDidLoad()
let stackView = UIStackView(arrangedSubviews: [view1, view2, view3])
stackView.translatesAutoresizingMaskIntoConstraints = false
stackView.axis = .horizontal
stackView.distribution = .fillEqually
stackView.spacing = 50 //add amount of space between your views
view.addSubview(stackView)
view1.backgroundColor = .orange
view2.backgroundColor = .black
view3.backgroundColor = .gray
stackView.bottomAnchor.constraint(equalTo: view.safeAreaLayoutGuide.bottomAnchor, constant: -10).isActive = true
stackView.leadingAnchor.constraint(equalTo: view.safeAreaLayoutGuide.leadingAnchor, constant: 10).isActive = true
stackView.trailingAnchor.constraint(equalTo: view.safeAreaLayoutGuide.trailingAnchor, constant: -10).isActive = true
stackView.heightAnchor.constraint(equalToConstant: view.frame.size.height*0.1).isActive = true
}
}
For more about UIStackView with example check this: https://nshipster.com/uistackview
Output:

Answer 2

Welcome to Stackoverflow. Please read on UIStackView. And by using that stackView, you can easily achieve what you want to achieve in your screenshot.
import UIKit
class ViewController: UIViewController {
var view1 = UIView()
var view2 = UIView()
var view3 = UIView()
lazy var stackView: UIStackView = {
return UIStackView(arrangedSubviews: [
self.view1,
self.view2,
self.view3
])
}()
override func viewDidLoad() {
super.viewDidLoad()
view.addSubview(stackView)
view1.backgroundColor = .orange
view2.backgroundColor = .black
view3.backgroundColor = .gray
stackView.translatesAutoresizingMaskIntoConstraints = false
stackView.axis = .horizontal
stackView.distribution = .equalSpacing
stackView.alignment = .center
view1.translatesAutoresizingMaskIntoConstraints = false
view2.translatesAutoresizingMaskIntoConstraints = false
view3.translatesAutoresizingMaskIntoConstraints = false
NSLayoutConstraint.activate([
self.stackView.leadingAnchor.constraint(equalTo: self.view.leadingAnchor, constant: 16),
self.stackView.trailingAnchor.constraint(equalTo: self.view.trailingAnchor, constant: -16),
self.stackView.bottomAnchor.constraint(equalTo: self.view.bottomAnchor, constant: -16),
self.view1.heightAnchor.constraint(equalToConstant: view.frame.size.height*0.1),
self.view1.widthAnchor.constraint(equalToConstant: view.frame.size.height*0.1),
self.view2.heightAnchor.constraint(equalToConstant: view.frame.size.height*0.1),
self.view2.widthAnchor.constraint(equalToConstant: view.frame.size.height*0.1),
self.view3.heightAnchor.constraint(equalToConstant: view.frame.size.height*0.1),
self.view3.widthAnchor.constraint(equalToConstant: view.frame.size.height*0.1)
])
}
}
RESULT: