Flutter Https 未处理异常：无效参数

Question

I want to show data in listview (example as hardcode)

When I want to get the value it's not working

I/flutter ( 9640): [{"No":0,"interest":"0.00","balance":"11,000,000,000.00","principal":"0.00","Installment":"0.00","Status":true},{"No":1,"interest":"110,000,000.00","balance":"0.00","principal":"11,000,000,000.00","Installment":"11,110,000,000.00","Status":true}]
I/flutter ( 9640): true
E/flutter ( 9640): [ERROR:flutter/lib/ui/ui_dart_state.cc(199)] Unhandled Exception: Invalid argument(s)
E/flutter ( 9640): #0      _StringBase.+ (dart:core-patch/string_patch.dart:272:57)

here is FetchData async

 List<LoanModel> _loanmodel = <LoanModel>[];

  Future<LoanModel> _fetchData() async {
    setState(() {
      loading = true;
    });
    final response =
    await http.get("http://192.168.0.23/Api/loansimulation.php?periodtime=" + periodtime + "&interestpermonth=" + interestpermonth + "&loanamountrequest=" +loanamountrequest); //with hardcode working fine
    if (response.statusCode == 200) {
      final data = jsonDecode(response.body);
      setState(() {
        for (Map i in data) {
          _loanmodel.add(LoanModel.fromJson(i));
        }
        loading = false;
      });
    }
  }

How to get the value of periodtime, interestpermonth and loanamountrequest from API and get value based on input value in flutter?

Answer 1

So I mentioned the below example how can you show the data you can fetch from this function.

    listView.Builder(

     itemcount=_loanmodel.length;
     builder(context,index)
    {
     return Container(
    child:Column(
    childern[
    Text(_loanmodel[index].balance)
    ])
    );
    }