参数类型“String”不能分配给参数类型“List<Widget>”

Question

飞镖 >我在我的第一个个人开支应用程序中遇到问题。我在他们的日常开支图表中遇到了这个问题。请为我提供有关该问题的正确解决方案

import 'package:flutter/material.dart';
import './transaction.dart';
import 'package:intl/intl.dart';

class Chart extends StatelessWidget {
  final List <Transaction> recenttransaction;
  Chart(this.recenttransaction);

  List <Map<String,Object>> get groupedTransactionValues{
    return List.generate(7, (index) {
      final weekday = DateTime.now().subtract(Duration(days: index),);
      var totalSum = 0.0;

      for(var i=0 ; i<recenttransaction.length;i++){
        if(recenttransaction[i].date.day == weekday.day &&
        recenttransaction[i].date.month == weekday.month &&
        recenttransaction[i].date.year == weekday.year){
          totalSum += recenttransaction[i].amount;
        }
      }
      // print(DateFormat.E().format(weekday));
      // print(totalSum);

      return {"day":DateFormat.E().format(weekday).substring(0,1),"amount":totalSum};
    });
  }


  @override
  Widget build(BuildContext context) {
    // print(groupedTransactionValues);
    return Card(
      elevation: 6,
      margin: EdgeInsets.all(20),
     child: Row(
       **Error part**
       children: groupedTransactionValues.map((data){
       return Text('${data['data']} : ${data['amount']}');
       }).toString(),

      ));
  }
}

Answer 1

改变

 children: groupedTransactionValues.map((data){
       return Text('${data['data']} : ${data['amount']}');
       }).toString(),

到

 children: groupedTransactionValues.map((data){
       return Text('${data['data']} : ${data['amount']}');
       }).toList(),