How to use MDCSnackbar on iOS 13?

Question

I am trying to use MDCSnackBar on my app.

my code

        let message = MDCSnackbarMessage()
        let action = MDCSnackbarMessageAction()
        let actionHandler = {() in
            let answerMessage = MDCSnackbarMessage()
            answerMessage.text = "Fascinating"
            MDCSnackbarManager.default.show(answerMessage)
        }
        action.handler = actionHandler
        action.title = "OK"
        message.action = action
        message.accessibilityLabel = "asd"
        message.accessibilityHint = "qwe"
        MDCSnackbarManager.default.show(message)

but didn't show anything in simulator nor real device. both iOS 13 any suggesstion ?