Future incompatibility

Question

I extract data from the Firebase to make a list of FLSpots and try to assign it to LineChartBarData(spots: ) but the incompatibility doesn't allow it.

static Future<List<FlSpot>> _getDataFromFirestore() async {

  ...
  ...

  List<FlSpot> spots = listData.asMap().entries.map((e) {
    return FlSpot(e.key.toDouble(), e.value);
  }).toList();

  // print(spots);
  return spots;

how can I assign it to avoid the error: The argument type 'Future<List<FlSpot>>' can't be assigned to the parameter type 'List<FlSpot>'. when I try

LineChartBarData(
          spots: _getDataFromFirestore(),

you should await for _getDataFromFireStore. You could use initState to load the data. And while the data is loading you show a loading indicator. That's the common approach for async data — RegularGuy, Sep 30 '20 at 16:01
https://stackoverflow.com/questions/63017280/what-is-a-future-and-how-do-i-use-it — Doug Stevenson, Sep 30 '20 at 16:09

score 0 · Answer 1 · answered Sep 30 '20 at 16:04

0

LineChartBarData(
          spots:await _getDataFromFirestore(),

use await keyword before calling the function.

answered Sep 30 '20 at 16:04

Abhishek Ghaskata

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No change, just throw me 'Unexpected text await.' – Hober Mark Sep 30 '20 at 21:22
Use steam Builder if you are using firebase – Abhishek Ghaskata Oct 01 '20 at 03:54

Future incompatibility

1 Answers1