Flutter在线支付功能插件online_payments_sdk的使用

好的，下面是一个完整的Flutter在线支付功能插件online_payments_sdk的使用示例。这个示例展示了如何初始化SDK、获取支付产品、加密支付请求以及处理响应。

import 'package:flutter/material.dart';
import 'package:online_payments_sdk/online_payments_sdk.dart';

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  [@override](/user/override)
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Online Payments Flutter SDK',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: MyHomePage(),
    );
  }
}

class MyHomePage extends StatefulWidget {
  [@override](/user/override)
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  Session session;
  PaymentProduct paymentProduct;

  void initState() {
    super.initState();
    // 初始化Session
    session = Session(
      "47e9dc332ca24273818be2a46072e006", // client session id
      "9991-0d93d6a0e18443bd871c89ec6d38a873", // customer id
      "https://clientapi.com", // client API URL
      "https://assets.com", // asset URL
      isEnvironmentProduction: false, // states if the environment is production
      appIdentifier: "Flutter Example Application/v1.0.0", // application identifier
      loggingEnabled: true, // Controls whether logging is enabled - use for development purposes.
    );

    // 获取支付产品
    paymentProductResponseListener = PaymentProductResponseListener(
      onSuccess: (response) {
        setState(() {
          paymentProduct = response.paymentProduct;
        });
      },
      onError: (apiError) {
        print('Error retrieving payment product: $apiError');
      },
      onException: (throwable) {
        print('Exception while retrieving payment product: $throwable');
      },
    );

    await session.getPaymentProduct(
      request: PaymentProductRequest(
        productId: "1", // id of the payment product you want to retrieve
        paymentContext: paymentContext, // PaymentContext
      ),
      listener: paymentProductResponseListener, // listener to be called when the payment product is retrieved or an error occurred
    );
  }

  void onEncryptPaymentRequest(PaymentRequestPreparedListener paymentRequestPreparedListener) async {
    // 加密支付请求
    paymentRequestPreparedListener = PaymentRequestPreparedListener(
      onSuccess: (response) {
        print('Encrypted fields: $response');
      },
      onError: (apiError) {
        print('Error encrypting payment request: $apiError');
      },
      onException: (throwable) {
        print('Exception while encrypting payment request: $throwable');
      },
    );

    await session.preparePaymentRequest(
      request: paymentRequest, // the payment request that should be encrypted
      listener: paymentRequestPreparedListener, // listener to be called when the payment request is encrypted
    );
  }

  void onCreatePaymentRequest(String encryptedFields) async {
    // 创建支付请求
    await createPaymentRequest(encryptedFields);
  }

  void createPaymentRequest(String encryptedFields) async {
    // 从服务器创建支付请求
    // 将加密字段传递给服务器进行处理
  }

  [@override](/user/override)
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Online Payments'),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            Text('Welcome to Online Payments'),
            SizedBox(height: 2),
            ElevatedButton(
              onPressed: () {
                // 初始化Session
                session = Session(
                  "47e9dc332ca24273818be2a46072e006", // client session id
                  "9991-0d93d6a0e18443bd871c89ec6d38a873", // customer id
                  "https://clientapi.com", // client API URL
                  "https://assets.com", // asset URL
                  isEnvironmentProduction: false, // states if the environment is production
                  appIdentifier: "Flutter Example Application/v11.0.0", // application identifier
                  loggingEnabled: true, // Controls whether logging is enabled - use for development purposes.
                );

                // 获取支付产品
                paymentProductResponseListener = PaymentProductResponseListener(
                  onSuccess: ( response {
                    setState(() {
                      paymentProduct = response.paymentProduct;
                    });
                  },
                  onError: ( apiError {
                    print('Error retrieving payment product: $apiError');
                  },
                  onException: : throwable {
                    print('Exception while retrieving payment product: $throwable');
                  },
                );

                await session.getPaymentProduct(
                  request: PaymentProductRequest(
                    productId: "1", // id of the payment product you want to retrieve
                    paymentContext: paymentContext, // PaymentContext
                  ),
                  listener: paymentProductResponseListener, // listener to be called when the payment product is retrieved or an error occurred
                );
              },
              child: Text('Get Payment Product'),
            ),
            SizedBox(height: 1),
            ElevatedButton(
              onPressed: () {
                // 加密支付请求
                paymentRequestPreparedListener = PaymentRequestPreparedListener(
                  onSuccess: : response {
                    print('Encrypted fields: $response');
                  },
                  onError: : apiError {
                    print('Error encrypting payment request: $apiError');
                  },
                  onException: : throwable {
                    print('Exception while encrypting payment request: $throwable');
                  },
                );

                await session.preparePaymentRequest(
                  request: paymentRequest, // the payment request that should be encrypted
                  listener: paymentRequestPreparedListener, // listener to be called when the payment request is encrypted
                );
              },
              child: Text('Encrypt Payment Request'),
            ),
            SizedBox(height: 1),
            ElevatedButton(
              onPressed: () {
                // 创建支付请求
                await createPaymentRequest(encryptedFields);
              },
              child: Text('Create Payment Request'),
            ),
          ],
        ),
      ),
    );
  }
}