Fetch Api Data Automatically with Interval in Flutter

Futures can have 2 states: completed or uncompleted. Futures cannot "progress", but Streams can, so for your use case Streams make more sense.

You can use them like this:

Stream.periodic(Duration(seconds: 5)).asyncMap((i) => getSakaryaAir())

periodic emits empty events every 5 seconds and we use asyncMap to map that event into another stream, which get us the data.

Here is working example:

import 'package:flutter/material.dart';import 'package:http/http.dart' as http;class ExamplePage extends StatelessWidget {  Future<String> getSakaryaAir() async {    String url =        'https://www.random.org/integers/?num=1&min=1&max=6&col=1&base=10&format=plain&rnd=new';    final response =        await http.get(url, headers: {"Accept": "application/json"});    return response.body;  }  @override  Widget build(BuildContext context) {    return StreamBuilder(      stream: Stream.periodic(Duration(seconds: 5))          .asyncMap((i) => getSakaryaAir()), // i is null here (check periodic docs)      builder: (context, snapshot) => Text(snapshot.data.toString()), // builder should also handle the case when data is not fetched yet    );  }}

You can refactor your FutureBuilder to use a Future variable instead of calling the method in the FutureBuilder. This would require you to use a StatefulWidget and you can set up the future in your initState and update it by calling setState.

So you have a future variable field like:

Future< SakaryaAir> _future;

So your initState would look like this :

@override  void initState() {    super.initState();    setUpTimedFetch();  }

where setUpTimedFetch is defined as

  setUpTimedFetch() {    Timer.periodic(Duration(milliseconds: 5000), (timer) {      setState(() {        _future = getSakaryaAir();      });    });  }

Finally, your FutureBuilder will be changed to:

FutureBuilder<SakaryaAir>(          future: _future,          builder: (context, snapshot) {            //Rest of your code          }),

Here is a DartPad demo: https://dartpad.dev/2f937d27a9fffd8f59ccf08221b82be3