anchor.diff:  import 'package:flutter/material.dart';
  -import 'package:flutter/services.dart';
   import 'package:pay/pay.dart';
  -
  -Pay _googlePayClient = Pay.fromAsset('default_payment_profile.json');
   
   void main() {
     runApp(PayMaterialApp());
  
positive.code: }
  
  class _PaySampleAppState extends State<PaySampleApp> {
    void googlePayButtonPressed() async {
      var result = await _googlePayClient.showPaymentSelector(price: '99.99');
      debugPrint(result.toString());
    }
  
    Widget _getPaymentButtons() {
      return FutureBuilder<bool>(
        future: _googlePayClient.userCanPay(),
        builder: (context, snapshot) {
          if (snapshot.connectionState == ConnectionState.done) {
            if (snapshot.data == true) {
              return SizedBox(
                  width: double.infinity,
                  child: GooglePayButton(
                      color: GooglePayButtonColor.flat,
                      type: GooglePayButtonType.pay,
                      onPressed: googlePayButtonPressed));
            } else if (snapshot.hasError) {
              PlatformException exc = snapshot.error;
              return Text(exc.message);
            }
          }
  
          return CircularProgressIndicator();
        },
      );
    }
  
    @override
  
negative.code:             ),
            ),
            SizedBox(height: 15),
            Center(
              child: SizedBox(
                width: double.infinity,
                child: GooglePayButtonWidget(
                  paymentConfigurationAsset: 'default_payment_profile.json',
                  color: GooglePayButtonColor.flat,
                  type: GooglePayButtonType.pay,
                  onPressed: googlePayButtonPressed,
                  childOnError: Text('Google Pay is not available.'),
                  loadingIndicator: CircularProgressIndicator(),
                ),
              ),
            ),
            SizedBox(height: 15),
          ],
        ),
      );
    }
  }
  