3. Initiate payment - Drop Checkout

Drop flow

Drop flow is the standard flow for Cashfree payment gateway's React Native SDK. In this flow, SDK provides a pre-built native screen to facilitate a quick integration with our payment gateway. Your customers can fill in the necessary details here and complete the payment.

This mode handles all the business logic and UI Components to make the payment smooth and easy to use. The SDK allows the merchant to customize the UI in terms of color coding and payment modes shown.

Initiating the payment

To initiate the Drop checkout payment in the SDK, follow these steps

Create a CFSession object.
Create a CFPaymentComponents object.
Create a CFTheme object.
Create a Drop Checkout Payment object.
Set payment callback.
Initiate the payment using the payment object created from [step 4]

Create a session

The payment_session_id created from Step2 is used to authenticate the payment. The SDK exposes a class CFSession class which accepts the payment_session_id, Environment and order ID values.

Cashfree provides two environments, one being the sandbox environment for developers to test the payment flow and responses and the other being production environment which gets shipped to production. This environment can be set in this session object.

The values for environment can be either .SANDBOX or .PRODUCTION.

import {
  CFEnvironment,
  CFSession,
} from 'cashfree-pg-api-contract';

try {
      const session = new CFSession(
        'payment_session_id',
        'order_id',
        CFEnvironment.SANDBOX
      );
		} catch (e: any) {
      console.log(e.message);
		}

Payment Components

The Cashfree's Drop checkout allows the merchant to control the payment modes shown to their customer using the payment component parameter.

const paymentModes = new CFPaymentComponentBuilder()
        .add(CFPaymentModes.CARD)
        .add(CFPaymentModes.UPI)
        .add(CFPaymentModes.NB)
        .add(CFPaymentModes.WALLET)
        .add(CFPaymentModes.PAY_LATER)
        .build();

If this method is not called, by default all the payment modes are enabled.

Set a Theme

const theme = new CFThemeBuilder()
        .setNavigationBarBackgroundColor('#E64A19')
        .setNavigationBarTextColor('#FFFFFF')
        .setButtonBackgroundColor('#FFC107')
        .setButtonTextColor('#FFFFFF')
        .setPrimaryTextColor('#212121')
        .setSecondaryTextColor('#757575')
        .build();

The CFThemeBuilder class used to create CFTheme used to set the theming for Drop checkout screen.

Create a Drop Checkout Payment object

Code Snippet to create a payment object for Drop Checkout (pre-built UI SDK)

try {
  const dropPayment = new CFDropCheckoutPayment(
        session,
        paymentModes,
        theme
      );
	CFPaymentGatewayService.doPayment(dropPayment);
	} catch (e: any) {
		console.log(e.message);
	}

📘
If payment component object is not provided then all the payment modes that are enabled for the merchant account is shown.

Setup Payment Callback

The SDK exposes an interface CFCallback to receive callbacks from the SDK once the payment flow ends.

This protocol comprises of 2 methods:

public void onVerify(String orderID)
public void onError(CFErrorResponse cfErrorResponse, String orderID)

Code snippet demonstrating it's usage:

import {
  CFErrorResponse,
  CFPaymentGatewayService,
} from 'react-native-cashfree-pg-sdk';

export default class App extends Component {
  constructor() {
    super();
  }
  
  componentDidMount() {
    console.log('MOUNTED');
    CFPaymentGatewayService.setCallback({
      onVerify(orderID: string): void {
        this.changeResponseText('orderId is :' + orderID);
      },
      onError(error: CFErrorResponse, orderID: string): void {
        this.changeResponseText(
          'exception is : ' + JSON.stringify(error) + '\norderId is :' + orderID
        );
      },
    });
  }

  componentWillUnmount() {
    console.log('UNMOUNTED');
    CFPaymentGatewayService.removeCallback();
  }
}

🚧
Make sure to set the callback at componentDidMount and remove the callback at componentWillUnmount as this also handles the activity restart cases and prevents memory leaks.

Sample Code

import * as React from 'react';
import { Component } from 'react';

import {
  CFErrorResponse,
  CFPaymentGatewayService,
} from 'react-native-cashfree-pg-api';
import {
  CFDropCheckoutPayment,
  CFEnvironment,
  CFPaymentComponentBuilder,
  CFPaymentModes,
  CFSession,
  CFThemeBuilder,
} from 'cashfree-pg-api-contract';

export default class App extends Component {

  constructor() {
    super();
  }
  
  componentDidMount() {
    console.log('MOUNTED');
    CFPaymentGatewayService.setCallback({
      onVerify(orderID: string): void {
        this.changeResponseText('orderId is :' + orderID);
      },
      onError(error: CFErrorResponse, orderID: string): void {
        this.changeResponseText(
          'exception is : ' + JSON.stringify(error) + '\norderId is :' + orderID
        );
      },
    });
  }

  componentWillUnmount() {
    console.log('UNMOUNTED');
    CFPaymentGatewayService.removeCallback();
  }

  async _startCheckout() {
    try {
      const session = new CFSession(
        'payment_session_id',
        'order_id',
        CFEnvironment.SANDBOX
      );
      const paymentModes = new CFPaymentComponentBuilder()
        .add(CFPaymentModes.CARD)
        .add(CFPaymentModes.UPI)
        .add(CFPaymentModes.NB)
        .add(CFPaymentModes.WALLET)
        .add(CFPaymentModes.PAY_LATER)
        .build();
      const theme = new CFThemeBuilder()
        .setNavigationBarBackgroundColor('#E64A19')
        .setNavigationBarTextColor('#FFFFFF')
        .setButtonBackgroundColor('#FFC107')
        .setButtonTextColor('#FFFFFF')
        .setPrimaryTextColor('#212121')
        .setSecondaryTextColor('#757575')
        .build();
      const dropPayment = new CFDropCheckoutPayment(
        session,
        paymentModes,
        theme
      );
      CFPaymentGatewayService.doPayment(dropPayment);
    } catch (e: any) {
      console.log(e.message);
    }
  }
}

You can check our demo app located here.

Updated 8 months ago