Flutter: Performing HTTP Requests with DART

 

An alternative to consume data from external data source within a Flutter APP is through the performance of HTTP Requests.

For this purpose, the first step is to import the http package, include a new dependency in pubspec.yaml file.



 

The you also has to include the permission to allow your APP to access internet. In case of ANDROID app, add a this permission statement in AndroidManifest.xml.

<uses-permission android:name="android.permission.INTERNET" />

 



 

Now you are ready to perform HTTP requests. In a .dart file include the following dependencies:

import 'package:http/http.dart' as http; //perform http request
import 'dart:convert'; // convert response string to JSON (map)

 

Now you are able to perform the HTTP request to a certain endpoint using a code like the one in the method below:

performHTTPRequest() async {

  String output="";

  final response = await http.get(Uri.parse('https://jsonplaceholder.typicode.com/albums/1'));

  if (response.statusCode == 200) {

    output=response.body;

    var json=jsonDecode(output);

    setState(() {

      this.data = output;

      this.title= json['title'];

    });

    print(response.body);

  } else {

    throw Exception('Failed to load data');

  }

  return output;

}

 

You may find the complete source code on github:  https://github.com/rafaelqg/code/blob/main/http_request_fetch.dart

You may also see a video class about how to perform the instructions described in this post.

https://www.youtube.com/watch?v=ZEnWA8c3e_4



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