BraintreeViewController for coordinating the Add Payment Method form.Activity encompassing Braintree's Drop-In UI.PaymentButton or Drop-in.PaymentButton or Drop-in.PaymentButton or Drop-in.String returned when specified in PaymentRequest that device data should be
collected.Activity.onActivityResult(int, int, android.content.Intent) if responseCode is not Activity.RESULT_OK or Activity.RESULT_CANCELEDPaymentMethodNonce returned by successfully exiting the flow.Intent that can be used in Activity.startActivityForResult(Intent, int)
to launch BraintreePaymentActivity and the Drop-in UI.PaymentButton using the CheckoutRequest and add it
to the Activity's FragmentManager.BaseAdapter to handle a List of PaymentMethodNonces.BraintreePaymentActivity and PaymentButton with specified options.ProgressBar with extra graphics for waiting states.BraintreeViewController for handling manipulation of existing payment method nonces.PaymentButton is clicked.PaymentButton.