viewcontroller thing

// https://github.com/andruzzzhka/BeatSaverDownloader/blob/master/BeatSaverDownloader/PluginUI/ViewControllers/SearchKeyboardViewController.cs
    class KeyboardViewController : HMUI.ViewController
    {
        GameObject keyboardGO;

        CustomUIKeyboard keyboard;

        TextMeshProUGUI _inputText;
        public string _inputString = "";

        public event Action<string> confirmPressed;
        public event Action cancelPressed;

        protected override void DidActivate(bool firstActivation, ActivationType type)
        {
            if (type == ActivationType.AddedToHierarchy && firstActivation)
            {
                var kb = Resources.FindObjectsOfTypeAll<UIKeyboard>().First(x => x.name != "CustomUIKeyboard");
                Logger.log.Debug("Found UIKeyboard object: " + kb);
                keyboardGO = Instantiate(kb, rectTransform, false).gameObject;

                Destroy(keyboardGO.GetComponent<UIKeyboard>());
                keyboard = keyboardGO.AddComponent<CustomUIKeyboard>();

                keyboard.textKeyWasPressedEvent += delegate (char input) { _inputString += input; UpdateInputText(); };
                keyboard.deleteButtonWasPressedEvent += delegate () { _inputString = _inputString.Substring(0, _inputString.Length - 1); UpdateInputText(); };
                keyboard.cancelButtonWasPressedEvent += () => { cancelPressed?.Invoke(); };
                keyboard.okButtonWasPressedEvent += () => { confirmPressed?.Invoke(_inputString); };

                _inputText = BeatSaberMarkupLanguage.BeatSaberUI.CreateText(rectTransform, "Enter PIN...", new Vector2(0f, 22f));
                _inputText.alignment = TextAlignmentOptions.Center;
                _inputText.fontSize = 6f;

            }
            else
            {
                _inputString = "";
                UpdateInputText();
            }

        }

        void UpdateInputText()
        {
            if (_inputText != null)
            {
                _inputText.text = _inputString?.ToUpper() ?? "";
                if (string.IsNullOrEmpty(_inputString) || _inputString.Length <= 5)
                {
                    keyboard.OkButtonInteractivity = false;
                }
                else
                {
                    keyboard.OkButtonInteractivity = true;
                }
            }
        }

        void ClearInput()
        {
            _inputString = "";
        }

        void Back()
        {
            _inputString = "";
            cancelPressed?.Invoke();
        }
    }