Why does UIView fill the superView? - ios

Question

I am creating a subview programmatically that I would like to be positioned over a superView, but I do not want it to fill the enter superView.
I have been checking around to see if this question has been asked before but for some reason, I can only find answers to how to fill the entire view.
I would really appreciate it if someone could help critique my code and explain how to position a subView instead of filling the entire superview.
class JobViewController: UIViewController {
var subView : SubView { return self.view as! SubView }
var requested = false
let imageView: UIImageView = {
let iv = UIImageView(image: #imageLiteral(resourceName: "yo"))
iv.contentMode = .scaleAspectFill
iv.isUserInteractionEnabled = true
iv.translatesAutoresizingMaskIntoConstraints = false
return iv
}()
override func viewDidLoad() {
super.viewDidLoad()
view.addSubview(imageView)
imageView.fillSuperview()
subView.requestAction = { [ weak self ] in
guard let strongSelf = self else { return }
strongSelf.requested = !strongSelf.requested
if strongSelf.requested {
UIView.animate(withDuration: 0.5, animations: {
strongSelf.subView.Request.setTitle("Requested", for: .normal)
strongSelf.subView.contentView.backgroundColor = UIColor.red.withAlphaComponent(0.5)
})
} else {
UIView.animate(withDuration: 0.5, animations: {
strongSelf.subView.Request.setTitle("Requested", for: .normal)
strongSelf.subView.contentView.backgroundColor = UIColor.blue
})
}
}
}
override func loadView() {
// I know the issue lies here, but how would I go about setting the frame of the subview to just be positioned on top of the mainView?
self.view = SubView(frame: UIScreen.main.bounds)
}
}
I have my subView built in a separate file, I am not sure whether or not I would need its information since It is just what is inside of the subview.

Answer 1

You should add your subView as a subview of self.view and not set it equal your main view. And then set the constraints accordingly.
override func viewDidLoad() {
self.view.addSubview(subView)
subview.translatesAutoresizingMaskIntoConstraint = false
addSubview.leadingAnchor.constraint(equalTo: self.view.leadingAnchor, constant: 0).isActive = true
addSubview.trailingAnchor.constraint(equalTo: self.view.trailingAnchor, constant: 0).isActive = true
addSubview.topAnchor.constraint(equalTo: self.view.topAnchor, constant: 0).isActive = true
addSubview.bottomAnchor.constraint(equalTo: self.view.bottomAnchor, constant: 0).isActive = true
}
Regarding your initialisation problem try:
var subView = SubView()
I hope I understood your question correct.