Ytukyg

In my project, I made a subclass of a UIView, which is basically a container for a UITextField. Everything works fine except that I get a strange error message in my console when I am selecting the textfield on screen, and I don't know how to do to make it disapear :

[Snapshotting] Snapshotting a view (0x119d2d240, _UIReplicantView)
that has not been rendered at least once requires
afterScreenUpdates:YES.

I tried to place some view.layoutIfNeeded() at some points but the message remains. Here is my code :

import UIKit



class BTShimmerTextField: BTShimmerView {



    let nestedTextField = UITextField()



    var didPressReturn: (() -> ())? = nil



    var placeholder: String? {

        get {

            return nestedTextField.placeholder

        }

        set {

            nestedTextField.placeholder = newValue

        }

    }



    var darkColor: UIColor? {

        get {

            return darkView.backgroundColor

        }

        set {

            darkView.backgroundColor = newValue

        }

    }



    var lightColor: UIColor? {

        get {

            return lightView.backgroundColor

        }

        set {

            lightView.backgroundColor = newValue

        }

    }



    var isSecureTextEntry: Bool {

        get {

            return nestedTextField.isSecureTextEntry

        }

        set {

            nestedTextField.isSecureTextEntry = newValue

        }

    }



    var autocorrectionType: UITextAutocorrectionType {

        get {

            return nestedTextField.autocorrectionType

        }

        set {

            nestedTextField.autocorrectionType = newValue

        }

    }



    override init(){

        super.init()

        setupTextField()

    }



    override init(frame: CGRect) {

        super.init(frame: frame)

        setupTextField()

    }



    required init?(coder aDecoder: NSCoder) {

        super.init(coder: aDecoder)

        setupTextField()

    }



    fileprivate func setupTextField(){



        nestedTextField.backgroundColor = UIColor.white // UIColor(named: "BTDark")

        nestedTextField.textAlignment = .center

        nestedTextField.tintColor = UIColor(named: "BTDark")

        nestedTextField.font = UIFont(name: "Metropolis-Regular", size: 16)

        nestedTextField.keyboardAppearance = .dark

        nestedTextField.delegate = self



        self.addSubview(nestedTextField)



        nestedTextField.anchor(top: self.topAnchor, leading: self.leadingAnchor, trailing: self.trailingAnchor, bottom: self.bottomAnchor, padding: UIEdgeInsets(top: 2, left: 2, bottom: 2, right: 2))



    }



    @discardableResult

    override func becomeFirstResponder() -> Bool {

        return nestedTextField.becomeFirstResponder()

    }



}



extension BTShimmerTextField: UITextFieldDelegate {

    func textFieldShouldReturn(_ textField: UITextField) -> Bool {

        if textField == nestedTextField {

            nestedTextField.resignFirstResponder()

            if let didPressReturn = didPressReturn { didPressReturn() } 

            return false

        }

        return true

    }

}

Note: The BTShimmerView is also a subclass of a UIView, in which I set 2 UIView with 2 different backgrounds, with a CAGradientLayer to make some kind of reflection effect.

Here is how I add it to my view :

import UIKit



class LoginViewController: UIViewController {



    override var prefersStatusBarHidden: Bool {

        return true

    }





    var loginView = BTShimmerTextField()

    var passwordView = BTShimmerTextField()



    override func viewDidLoad() {

        super.viewDidLoad()

        view.backgroundColor = UIColor(named: "BTDark")

        setupLoginViews()



    }





    fileprivate func setupLoginViews(){



        loginView.darkColor = UIColor(named: "BTDarkGold")

        loginView.lightColor = UIColor(named: "BTGold")

        loginView.placeholder = "Identifiant"

        loginView.didPressReturn = { self.passwordView.becomeFirstResponder() }

        loginView.autocorrectionType = .no

        view.addSubview(loginView)



        loginView.translatesAutoresizingMaskIntoConstraints = false

        loginView.heightAnchor.constraint(equalToConstant: 30).isActive = true

        loginView.widthAnchor.constraint(equalTo: view.widthAnchor, multiplier: 0.7).isActive = true

        loginView.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true

        loginView.centerYAnchor.constraint(equalTo: view.centerYAnchor, constant: -25).isActive = true





        passwordView.darkColor = UIColor(named: "BTDarkGold")

        passwordView.lightColor = UIColor(named: "BTGold")

        passwordView.placeholder = "Mot de passe"

        passwordView.isSecureTextEntry = true

        passwordView.autocorrectionType = .no

        view.addSubview(passwordView)



        passwordView.translatesAutoresizingMaskIntoConstraints = false

        passwordView.heightAnchor.constraint(equalToConstant: 30).isActive = true

        passwordView.widthAnchor.constraint(equalTo: view.widthAnchor, multiplier: 0.7).isActive = true

        passwordView.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true

        passwordView.centerYAnchor.constraint(equalTo: view.centerYAnchor, constant: 25).isActive = true





    }



}

Does anyone know how I can resolve this error? Is this error really problematic?

Found the solution. I had to set my constraints by overriding updateConstraints method, considering it's a subclass, like so :

[...]

// Constraints

override func updateConstraints() {

    if(shouldSetupConstraints) {

        setupTextFieldConstraints()

    }

    super.updateConstraints()

}



fileprivate func setupTextFieldConstraints(){

     nestedTextField.anchor(top: self.topAnchor, leading: self.leadingAnchor, trailing: self.trailingAnchor, bottom: self.bottomAnchor, padding: UIEdgeInsets(top: 2, left: 2, bottom: 2, right: 2))

}

[...]