default authenticator activity

AuthenticatorActivity.kt

package com.amazon.aws.mobile.samples.tasks.activities

import android.support.v7.app.AppCompatActivity
import android.os.Bundle
import com.amazon.aws.mobile.samples.tasks.providers.AWSProvider
import com.amazonaws.mobile.auth.ui.SignInUI

class AuthenticatorActivity : AppCompatActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)

        // Pull in the SignInUI
        val ui = AWSProvider.instance!!.getClient(this, SignInUI::class.java) as SignInUI
        ui.login(this, MainActivity::class.java).execute()
    }
}