Flutter Payment Plugin — Step‑by‑Step Integration #

This guide explains how to add and use flutter_payment_plugin in any Flutter app.

1) Add the Package #

• Run: flutter pub add flutter_payment_plugin
• Import: import 'package:flutter_payment_plugin/flutter_payment_plugin.dart';

2) Android Setup #

• No additional Android changes are required.

3) iOS Setup #

• To make the deep links to open payment apps, add these URL schemes to ios/<YourAppName>/Info.plist:

<key>LSApplicationQueriesSchemes</key>
<array>
  <!-- Add the schemes you plan to support -->
  <string>upi</string>
  <string>gpay</string>
  <string>phonepe</string>
  <string>paytm</string>
  <!-- etc. -->
</array>

4) Prepare Your Inputs #

• url: your payment gateway base domain (e.g., https://your-gateway.example)
• params must include at least: api_key, order_id, salt, hash, mode, amount, name, phone, email, return_url
• Optional fields as required by your gateway: description, currency, country, city, state, address_line_1, address_line_2, zip_code, enable_auto_refund, udf1–udf5
• Generate hash according to your gateway’s spec (recommended on backend).

5) Trigger the Payment #

Future<void> startPayment() async {
  final params = <String, String>{
    'api_key': 'YOUR_API_KEY',
    'order_id': 'YOUR_ORDER_ID',
    'salt': 'YOUR_SALT',
    'hash': 'YOUR_GENERATED_HASH',
    'mode': 'LIVE',
    'amount': '100',
    'name': 'Buyer Name',
    'phone': '9999999999',
    'email': 'buyer@example.com',
    'return_url': 'https://your.domain/return',
    // optional fields...
  };

  final result = await FlutterPaymentPlugin.openPayment(
    url: 'https://your-gateway.example',
    params: params,
    title: 'Payment',
    javaScript: true,
  );

  if (result.cancelled) {
    // Handle cancellation
  } else if (result.success) {
    // Handle success, check result.data if provided
  } else {
    // Handle failure, inspect result.data
  }
}

6) Integration Tips #

• Ensure all required fields are set and trimmed.
• Use a reachable return_url provided by your gateway.
• Prefer generating hash securely on your backend.
• Payment initiation endpoint is fixed: BASE_URL + /v2/paymentrequest. Provide only the base url.

7) Common Issues #

• Wrong endpoint: ensure your base url is correct; the request path is always /v2/paymentrequest.
• Network errors: check device connectivity and the base url.
• iOS deep links: add URL schemes for the apps your flow targets.