The right way for implementation of a view hierarchy in UIViewController

Question

Created Mar ’21

Replies 2

Boosts 0

Participants 3

Hello to everybody 👋

I and my coworkers can't solve a dispute about initialization of a view hierarchy for a long time. We implement a view hierarchy from code, without using Interface Builder. Each of us has own background experience about how it should work "right". If everything is clearly and understandably in Objective-C, there are some questions in Swift on which Apple hasn't answered.

We have three technical solutions and each of us applies own solution:

1️⃣

Code Block swiftclass SomeClass: UIViewController {
    
    private var someLabel: UILabel!
    private var someSwitch: UISwitch!
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        let someLabel = UILabel()
        someLabel.text = "Test"
        view.addSubview(someLabel)
        self.someLabel = someLabel
        let someSwitch = UISwitch()
        someSwitch.isOn = true
        view.addSubview(someSwitch)
        self.someSwitch = someSwitch
    }
}

2️⃣

Code Block swiftclass SomeClass: UIViewController {
    
    private let someLabel = UILabel()
    private let someSwitch = UISwitch()
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        someLabel.text = "Test"
        view.addSubview(someLabel)
        
        someSwitch.isOn = true
        view.addSubview(someSwitch)
    }
}

3️⃣

Code Block swiftclass SomeClass: UIViewController {
    
    private lazy var someLabel = UILabel()
    private lazy var someSwitch = UISwitch()
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        someLabel.text = "Test"
        view.addSubview(someLabel)
        
        someSwitch.isOn = true
        view.addSubview(someSwitch)
    }
}

I suppose that the same question has already discussed here, but I haven't found a discussion. If you know where there was the discussion, please, send to me.

Boost

Answer 1

OOPer OP

Mar ’21

I haven't found a discussion.

Neither have I.

I guess, the most preferred way by Apple would be using Interface Builder:

Code Block class SomeVC: UIViewController {
    
    @IBOutlet private weak var someLabel: UILabel!
    @IBOutlet private weak var someSwitch: UISwitch!
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
    }
}

If you do not prefer Apple's way, unless you have some reason to be forced to use 1️⃣ or 3️⃣, I would use 2️⃣.
For only one reason that it can represent someLabel and someSwitch may not be replaced.

But, as already noted, I have never found this sort of discussion in the dev forums, so not sure my opinion would be sort of leading or not.

0

Answer 2

Claude31 OP

Mar ’21

If you create programmatically, you need to define the frame or create constraints to position correctly the label in view.

But I do prefer using IB. Much simpler and it lets other understand what the UI design is. A big plus when working in team.

0