The method '[]' was called on null, but it's not null

Question

That title error is pointed on this line:

Text('${intData['summary']['intrested']}')

I want to display here data from backend, but I don't know how to accomplish that I am getting this error, but this is not null.

Here is my code:


var intData;

Future<Map> loadMyFriends(String eventId) async {
    
    var request = await EndPoints.interest(eventId, userId);
    print(request.body);
    intData = jsonDecode(request.body)['data'] as Map;
    return jsonDecode(request.body)['data'];
  }


@override
  void initState() {
    super.initState();
    userId = widget.userId;
    loadMyFriends(widget.partyMap['id']).then((value) => print('$intData'));
  }

@override
  void didUpdateWidget(SquareBoxMovableBuilder oldWidget) {
    super.didUpdateWidget(oldWidget);
    if (widget.partyMap != oldWidget.partyMap) {
      loadMyFriends(widget.partyMap['id']);
      print(intData);
    }
  }

and here are console prints what intData contains:

//print(request.body) in loadMyFriends function
{"data":{"intrested":null,"participate":null,"summary":{"intrested":0,"participate":0},"friends":{"list":[],"sum":0}}}

//print(intData) in initState
{intrested: null, participate: null, summary: {intrested: 0, participate: 0}, friends: {list: [], sum: 0}}

//print(intData) in didUpdateWidget
{intrested: null, participate: null, summary: {intrested: 0, participate: 0}, friends: {list: [], sum: 0}}

I tried to do this with FutureBuilder but I had same result. How to fix it or how to do it? How to display data downloaded from backend every time when I open this widget?

that's why you have that error, what you really need is `FutureBuilder` - first check the official docs for that class - they have some sample code — pskink, Jul 04 '22 at 14:22
most likely you didn't follow the sample code from the official docs — pskink, Jul 04 '22 at 14:23
more here https://api.flutter.dev/flutter/widgets/FutureBuilder-class.html — pskink, Jul 04 '22 at 14:27

score 0 · Answer 1 · answered Jul 04 '22 at 14:18

0

While the loadMyFriends is a future method and it will take some time to get data and after getting data you need to call setState((){}) to update the UI. You can try on

Future<Map> loadMyFriends(String eventId) async {
    
    var request = await EndPoints.interest(eventId, userId);
    print(request.body);
    intData = jsonDecode(request.body)['data'] as Map;
    setState((){}); //here
    return jsonDecode(request.body)['data'];
  }

answered Jul 04 '22 at 14:18

Md. Yeasin Sheikh

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It's launching now, but error screen its still showing, for 1 second, maybe less, but it's showing. – Karol Wiśniewski Jul 04 '22 at 14:23
It's showing and it's dissappear immediately – Karol Wiśniewski Jul 04 '22 at 14:24
Can you remove from `didUpdateWidget` for now. – Md. Yeasin Sheikh Jul 04 '22 at 14:25
It's happening only on initState actually – Karol Wiśniewski Jul 04 '22 at 14:26
try to create another x method and place it inside initState, then put `loadMyFriends` inside x method. also you need to make x method as async. If it fails can you include full widget of [minimal-reproducible-example](https://stackoverflow.com/help/minimal-reproducible-example), initState cant be async – Md. Yeasin Sheikh Jul 04 '22 at 14:29

The method '[]' was called on null, but it's not null

1 Answers1