使用Firebase Auth预制UI登录时如何添加onCompleteListener？

Question

我正在使用prebuilt Firebase UI对用户进行身份验证，如下所示：

val providers = arrayListOf(
            AuthUI.IdpConfig.EmailBuilder().build(),
            AuthUI.IdpConfig.GoogleBuilder().build())

startActivityForResult(
            AuthUI.getInstance().createSignInIntentBuilder()
                    .setAvailableProviders(providers)
                    .build(),
            RC_SIGN_IN)

如何在登录过程中附加OnCompleteListener？更具体地说，我想调用getAdditionalUserInfo().isNewUser()来检查用户是否是首次登录。我知道如果我使用onCompleteListener登录可以添加email and password-based method，但是我想使用上面的预构建UI方法。

Answer 1

override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
    super.onActivityResult(requestCode, resultCode, data)

    if (requestCode == RC_SIGN_IN) {

        // this class has all the needed data !
        val response = IdpResponse.fromResultIntent(data)

        if (resultCode == Activity.RESULT_OK) {
            // Successfully signed in            
            val isNewUser = response?.isNewUser!! // flag to check if the user is first time login 
        } 
    }
}