import IQKeyboardReturnManager

class ViewController: UIViewController {

    let returnManager: IQKeyboardReturnManager = .init()

    override func viewDidLoad() {
        super.viewDidLoad()

        // This will add all textInputView of the controller and start observing for textFieldShouldReturn events
        returnManager.addResponderSubviews(of: self.view, recursive: true)

        // If you would like to dismiss the UITextView on tapping on return then add this
        returnManager.dismissTextViewOnReturn = true

        // If you would like to change last textInputView return key type to done or something else, then add this
        returnManager.lastTextInputViewReturnKeyType = .done

        // If you would like to customize the navigation between textField by your own order then add them manually
        returnManager.add(textInputView: textField1)
        returnManager.add(textInputView: textField2)
        returnManager.add(textInputView: textField3)
        returnManager.add(textInputView: textField4)
    }
}

// IQKeyboardReturnManager will forward all delegate callbacks to you, so you can customize the decisions 
extension ViewController: UITextFieldDelegate {
    @objc public func textFieldShouldBeginEditing(_ textField: UITextField) -> Bool {...}
}