UITextField, UITextView 입력 시 키보드창 가려짐 방지

UITextField, UITextView 입력 시 키보드가 활성화될 때 키보드에 가려지지 않도록 하는 방법을 알아보도록 한다.

아래 샘플은 UITableView에서 입력 시 키보드에 가려지지 않도록 처리하는 예제이다.

class ViewController: UIViewController, UITextFieldDelegate, UITextViewDelegate, UITableViewDataSource, UITableViewDelegate {
    @IBOutlet weak var tableView: UITableView!

    private var activeTextField: UITextField?
    private var activeTextView: UITextView?

    override func viewDidLoad() {
        super.viewDidLoad()
        tableView.delegate = self
        tableView.dataSource = self
        registerForKeyboardNotifications()
    }
	... 중간 생략 ...
    
    
    // 활성화된 TextView 입력 필드를 추적 및 갱신
    func textFieldDidBeginEditing(_ textField: UITextField) {
        activeTextField = textField
        activeTextView = nil
    }
    
    func textFieldDidEndEditing(_ textField: UITextField) {
        activeTextField = nil
    }
    
    
	// 활성화된 TextView 입력 필드를 추적 및 갱신
    func textViewDidBeginEditing(_ textView: UITextView) {
        activeTextView = textView
        activeTextField = nil
    }
    
    func textViewDidEndEditing(_ textView: UITextView) {
        activeTextView = nil
    }
}

extension ViewController {
	// 키보드가 나타날 때, 키보드가 내려갈 때 이벤트 등록
    func registerForKeyboardNotifications() {
        NotificationCenter.default.addObserver(self, selector: #selector(keyboardWasShown(_:)), name: UIResponder.keyboardDidShowNotification, object: nil)
        NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillBeHidden(_:)), name: UIResponder.keyboardWillHideNotification, object: nil)
    }
	
    // 키보드가 나타날 때 실행되며, 현재 활성화된 입력 필드가 키보드에 의해 가려지지 않도록 스크롤
    @objc func keyboardWasShown(_ notification: NSNotification) {
        guard let userInfo = notification.userInfo,
              let keyboardFrame = userInfo[UIResponder.keyboardFrameEndUserInfoKey] as? NSValue else { return }

        let keyboardRectangle = keyboardFrame.cgRectValue
        let keyboardHeight = keyboardRectangle.height

        let insets = UIEdgeInsets(top: 0, left: 0, bottom: keyboardHeight, right: 0)
        tableView.contentInset = insets
        tableView.scrollIndicatorInsets = insets

        var aRect = self.view.frame
        aRect.size.height -= keyboardHeight

        if let activeTextField = activeTextField, let textFieldRect = activeTextField.superview?.convert(activeTextField.frame, to: tableView) {
            if !aRect.contains(textFieldRect.origin) {
                tableView.scrollRectToVisible(textFieldRect, animated: true)
            }
        } else if let activeTextView = activeTextView, let textViewRect = activeTextView.superview?.convert(activeTextView.frame, to: tableView) {
            if !aRect.contains(textViewRect.origin) {
                tableView.scrollRectToVisible(textViewRect, animated: true)
            }
        }
    }
	
    // 키보드가 내려갈 때 
    @objc func keyboardWillBeHidden(_ notification: NSNotification) {
        tableView.contentInset = .zero
        tableView.scrollIndicatorInsets = .zero
    }
}