How to Check Internet Connection in Flutter

In this example, we are going to show you how to check the internet connection in Flutter. You will learn to check if the device's internet connection is online or offline, if the device is online, then check if its connection with mobile data, wifi, wired ethernet, or Bluetooth is threatening. See the example below:

First, add connectivity_plus package in your project by adding the following lines in pubspec.yaml file.

dependencies:
  flutter:
    sdk: flutter
  connectivity_plus: ^2.2.1

Now, import the package in your script:

import 'package:connectivity_plus/connectivity_plus.dart';

var result = await Connectivity().checkConnectivity();
if(result == ConnectivityResult.mobile) {
      print("Internet connection is from Mobile data");
}else if(result == ConnectivityResult.wifi) {
    print("internet connection is from wifi");
}else if(result == ConnectivityResult.ethernet){
    print("internet connection is from wired cable");
}else if(result == ConnectivityResult.bluetooth){
    print("internet connection is from bluethooth threatening");
}else if(result == ConnectivityResult.none){
    print("No internet connection");
}

Here, you can check if the connection is online or offline, if the internet connection is online then check if it is connected via mobile data, wifi, wired ethernet, or Bluetooth threatening.

You subscribe to the internet connection status update stream so that you can show the automatic offline or online messages on your app. For example:

import 'dart:async';

StreamSubscription? connection;
bool isoffline = false;

connection = Connectivity().onConnectivityChanged.listen((ConnectivityResult result) {
    // whenevery connection status is changed.
    if(result == ConnectivityResult.none){
          //there is no any connection
          setState(() {
              isoffline = true;
          }); 
    }else if(result == ConnectivityResult.mobile){
          //connection is mobile data network
          setState(() {
            isoffline = false;
          });
    }else if(result == ConnectivityResult.wifi){
        //connection is from wifi
        setState(() {
            isoffline = false;
        });
    }else if(result == ConnectivityResult.ethernet){
        //connection is from wired connection
        setState(() {
            isoffline = false;
        });
    }else if(result == ConnectivityResult.bluetooth){
        //connection is from bluetooth threatening
        setState(() {
            isoffline = false;
        });
    }
});

You can show messages on your widget tree like below:

Container(
    color: isoffline?Colors.red:Colors.lightGreen, 
            //red color on offline, green on online
    padding:EdgeInsets.all(10),
    child: Text(isoffline?"Device is Offline":"Device is Online", 
            style: TextStyle(
              fontSize: 20, color: Colors.white
          ),
        ),
)

For More Details: How to Show Automatic Internet Connection Offline Message in Flutter

import 'dart:async';
import 'package:connectivity_plus/connectivity_plus.dart';
import 'package:flutter/material.dart';


Future<void> main() async {
  runApp(MyApp());
}

class MyApp extends StatelessWidget{
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Home(),
    );
  }
}

class Home extends StatefulWidget{
  @override
  _HomeState createState() => _HomeState();
}

class _HomeState extends State<Home> {
  StreamSubscription? connection;
  bool isoffline = false;

  

  @override
  void initState() {
    connection = Connectivity().onConnectivityChanged.listen((ConnectivityResult result) {
        // whenevery connection status is changed.
        if(result == ConnectivityResult.none){
             //there is no any connection
             setState(() {
                 isoffline = true;
             }); 
        }else if(result == ConnectivityResult.mobile){
             //connection is mobile data network
             setState(() {
                isoffline = false;
             });
        }else if(result == ConnectivityResult.wifi){
            //connection is from wifi
            setState(() {
               isoffline = false;
            });
        }else if(result == ConnectivityResult.ethernet){
            //connection is from wired connection
            setState(() {
               isoffline = false;
            });
        }else if(result == ConnectivityResult.bluetooth){
            //connection is from bluetooth threatening
            setState(() {
               isoffline = false;
            });
        }
    });
    super.initState();
  }

  @override
  void dispose() {
    connection!.cancel();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) { 
    return  Scaffold(
          appBar: AppBar( 
              title: Text("Check Internet Connection"),
              backgroundColor: Colors.redAccent,
          ),
          body: Container( 
            alignment: Alignment.center,
            child: Column(
               children:[
                  Container( 
                      width: double.infinity,
                      alignment: Alignment.center,
                      margin: EdgeInsets.only(bottom:30),
                      color: isoffline?Colors.red:Colors.lightGreen, 
                             //red color on offline, green on online
                      padding:EdgeInsets.all(10),
                      child: Text(isoffline?"Device is Offline":"Device is Online", 
                             style: TextStyle(
                                fontSize: 20, color: Colors.white
                             ),),
                  ),

                  ElevatedButton(onPressed: () async {
                      var result = await Connectivity().checkConnectivity();
                      if(result == ConnectivityResult.mobile) {
                           print("Internet connection is from Mobile data");
                      }else if(result == ConnectivityResult.wifi) {
                          print("internet connection is from wifi");
                      }else if(result == ConnectivityResult.ethernet){
                          print("internet connection is from wired cable");
                      }else if(result == ConnectivityResult.bluetooth){
                          print("internet connection is from bluethooth threatening");
                      }else if(result == ConnectivityResult.none){
                          print("No internet connection");
                      }
                  }, 
                  child: Text("Check Internet Connection")
                )
               ]
            )
          ),
           
       );
  }
}

When Internet Connection is Online