custom interface kotlin for alert dialog

class CustomAlertDialogOneButton( activity: Activity?,
private val alertOneButtonClickListener: OnAlertOneButtonClickListener):Dialog(activity!!) {

private var title = ""
private var text = ""
private var dialogId = -1
private var buttonName = ""

override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.custom_alert_one_button_dialog)
    setCancelable(false)
    this.window?.setBackgroundDrawable(ColorDrawable(android.graphics.Color.TRANSPARENT))
    viewsClickListenerInit()
}

override fun onStart() {
    initDialog()
    super.onStart()
}

private fun fillFields(title: String, text: String?, dialogId: Int, buttonName: String) {
    clearDialog()
    this.title = title
    this.text = text ?: ""
    this.dialogId = dialogId
    this.buttonName = buttonName
}

private fun clearDialog() {
    title = ""
    text = ""
}

private fun initDialog() {
    if (title.isNotBlank()) {
        tvAlertTitle.text = title
    }

    if (text.isNotBlank()) {
        tvAlertText.text = text
    }

    tvAlertButtonOk.text = buttonName
}

fun show(title: String, text: String?, dialogId: Int = -1, buttonName: String = ResourcesRepository.resources.getString(R.string.ok)) {
    fillFields(title, text, dialogId, buttonName)
    super.show()
}

private fun viewsClickListenerInit() {
    tvAlertButtonOk.setOnClickListener {
        alertOneButtonClickListener.okClickListener(dialogId)
        dismiss()
    }
}}