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flutter - 如何在 onPressed Flutter 中声明一个变量？

问题描述

我正在尝试在onPressed. 但它说错误：expected {。有人可以展示一个 onPressed 的示例，其中一个变量被初始化、声明和使用？

这是我的代码：

import 'package:flutter/material.dart';
import 'package:http/http.dart' as http;

class TestingWidget extends StatefulWidget {
  @override
  _TestingWidgetState createState() => _TestingWidgetState();
}
var requestbody = {
  "apiKey":"z_P!EJ?dsverbtbspV3K4GxaET",
  "operationType":"register_user_otp",
  "operationData": {
    "email": "shewfwrvam@fvbtrg.com",
    "userName":"dvre",
    "accessKey":"2defr",
    "accessValue":"32rfg43v5",
    "registrationTimeStamp": 1616919213853
  }
};
var url = Uri.parse('https://script.google.com/macros/s/AKfycbz7kTROol8u509M_p9pMZ9XRnL-myVjcRQKeb9Etp_OIMPnH640vHf_0Jp2dvRIco7kOg/exec');


class _TestingWidgetState extends State<TestingWidget> {
  @override
  Widget build(BuildContext context) {
    return ElevatedButton(
      onPressed: () => {
        var response = await http.post(url, body: requestbody);
        print('Response status: ${response.statusCode}');
        print('Response body: ${response.body}');
      },
      child: new Text('Click me'),
    );
  }
}

标签： flutterdart

解决方案

对于匿名函数，使用=>或{}不使用两者。https://dart.dev/guides/language/language-tour#anonymous-functions

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