Integrate Stripe Android SDK in Payment Gateway

I have used many payment gateways in my projects till now. And I found that Stripe is providing a very simple way of integrating the library and also it is providing many types of payment methods like Card, Digital wallets, Bank debits, Authenticated bank debits, etc.

So Let’s begin with how to integrate stripe payment gateway in Android. To implement stripe in your project, go through the few steps which I have mentioned below.

Step 1 : Register project on stripe console. From there you will get a publishable key & secret key. For Android SDK, You will require only a publishable key. For stripe Android sdk integration, you will require only a publishable key.

Publishable API keys are meant solely to identify your account with Stripe, they aren’t secret. In other words, they can safely be published in places like your Stripe.js JavaScript code, or in an Android or iPhone app. Publishable keys only have the power to create tokens.

Step 2 : Add library to dependency section in build.gradle file.

implementation 'com.stripe:stripe-android:14.2.1'

Step 3 : Initialize payment configuration from your application class.

override fun onCreate() {
   super.onCreate()

PaymentConfiguration.init(applicationContext,resources.getString(R.string.stripe_publishable_key))

}

Step 4 : To initialize the Customer Session you need to get the Ephemeral key from the backend by calling APIs.

After getting Ephemeral key from backend you can initialize the customer session like below :

fun initializeCustomerSession(context: Context?, EphemeralKeyRawJson:String){

   context?.let {context->

       CustomerSession.initCustomerSession(
           context,
           StripeDemoEphemeralKeyProvider(EphemeralKeyRawJson)
       )
   }}


class StripeDemoEphemeralKeyProvider(private val ephemeralKeyRawJson: String) : EphemeralKeyProvider {

   override fun createEphemeralKey(
       @Size(min = 4) apiVersion: String,
       keyUpdateListener: EphemeralKeyUpdateListener
   ) {

       keyUpdateListener.onKeyUpdate(ephemeralKeyRawJson)

   }
}

Step 5 : If you want to save payment methods with your account for the later. Then you can directly call SDK’s Activity to save Payment Method :

PaymentMethodsActivityStarter(this)
   .startForResult(
       PaymentMethodsActivityStarter.Args.Builder()
           .build()
   )

Note: Before calling SDK’s activity make sure that you have initialized the customer Session.

Step 6 : For the payment you have to select any payment method which you had saved before or you can also add a new one at the time of payment.

Then call api to get client secret from backend, you will require amount, currency, customer to create payment intent, by creating payment intent you will get client secret in response. Using the client secret key you need to confirm payment.

private  var paymentMethodId:String="pm_1HJJ6nAKcjKtlZOHN79JOkPe"
private  val clientSecret:String="pi_1HJNNtAKcjKtlZOHbeYMvCLU_secret_FzF0mL6a94RkebcdJ5gvtHr0n"
private  var paymentSession: PaymentSession?=null



private fun makePayment() {
   initializeCustomerSession(this,"")
   paymentSession = PaymentSession(
       this,
       createPaymentSessionConfig()
   )

   paymentSession?.init(createPaymentSessionListener())

   PaymentMethodsActivityStarter(this)
       .startForResult(
           PaymentMethodsActivityStarter.Args.Builder()
               .build()
       )
}



private fun createPaymentSessionConfig(): PaymentSessionConfig {
   return PaymentSessionConfig.Builder()
       .setShippingMethodsRequired(false)
       .setShippingInfoRequired(false)
       .build()
}

private fun confirmPayment(
   clientSecret: String,
   paymentMethodId: String
) {

   stripe = Stripe(
       applicationContext,
       PaymentConfiguration.getInstance(this).publishableKey)

   stripe?.confirmPayment(
       this,
       ConfirmPaymentIntentParams.createWithPaymentMethodId(
           paymentMethodId,
           clientSecret
       )
   )

}

private fun createPaymentSessionListener(): PaymentSession.PaymentSessionListener {
   return object : PaymentSession.PaymentSessionListener {
       override fun onCommunicatingStateChanged(isCommunicating: Boolean) {
           Log.e(TAG,"onCommunicatingStateChanged "+isCommunicating)
       }

       override fun onError(errorCode: Int, errorMessage: String) {
           Log.e(TAG,"onError "+errorCode+"  "+errorMessage)
       }

       override fun onPaymentSessionDataChanged(data: PaymentSessionData) {
           Log.e(TAG,"onPaymentSessionDataChanged "+data.isPaymentReadyToCharge+"  "+data)

           if (data.isPaymentReadyToCharge){
               confirmPayment(
                   clientSecret,paymentMethodId
               )
           }
       }
   }
}



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

       data?.let {
           val result = PaymentMethodsActivityStarter.Result.fromIntent(data)

           val paymentMethod = result?.paymentMethod
           Log.e(TAG, "paymentMethodId : " + paymentMethod?.id)
           paymentMethodId = paymentMethod?.id.toString()
           paymentSession?.handlePaymentData(requestCode, resultCode, it)
       }
   }else {
       stripe?.onPaymentResult(
           requestCode,
           data,
           object : ApiResultCallback<PaymentIntentResult> {
               override fun onSuccess(result: PaymentIntentResult) {
                   val paymentIntent = result.intent
                   when (paymentIntent.status) {
                       StripeIntent.Status.Succeeded -> {
                           Log.e(TAG, "Payment Success")
                       }
                       StripeIntent.Status.RequiresPaymentMethod -> {
                           Log.e(
                               TAG,
                               "Payment Failed " + paymentIntent.lastPaymentError?.message
                           )
                       }
                       else -> {
                           Log.e(TAG, "Payment status unknown " + paymentIntent.status)

                       }
                   }
               }

               override fun onError(e: Exception) {
                   Log.e(TAG, "Payment Error " + e.localizedMessage)
               }
           })
   }
}

Git Source Code : https://github.com/kbmaradiya/StripePaymentAndroid

Reference : https://stripe.com/docs/mobile/android/basic