flutter_nearby_connections 0.0.4

Flutter plugin supports peer-to-peer connectivity and discovers nearby devices for Android and IOS

example/lib/main.dart

import 'dart:async';
import 'dart:convert';
import 'package:flutter/material.dart';
import 'package:flutter_nearby_connections/flutter_nearby_connections.dart';
import 'package:fluttertoast/fluttertoast.dart';

void main() {
  runApp(MyApp());
}

Route<dynamic> generateRoute(RouteSettings settings) {
  switch (settings.name) {
    case '/':
      return MaterialPageRoute(builder: (_) => Home());
    case 'browser':
      return MaterialPageRoute(
          builder: (_) => DevicesListScreen(deviceType: DeviceType.browser));
    case 'advertiser':
      return MaterialPageRoute(
          builder: (_) => DevicesListScreen(deviceType: DeviceType.advertiser));
    default:
      return MaterialPageRoute(
          builder: (_) => Scaffold(
                body: Center(
                    child: Text('No route defined for ${settings.name}')),
              ));
  }
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      onGenerateRoute: generateRoute,
      initialRoute: '/',
    );
  }
}

class Home extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Column(
        children: [
          Expanded(
            child: InkWell(
              onTap: () {
                Navigator.pushNamed(context, 'browser');
              },
              child: Container(
                color: Colors.red,
                child: Center(
                    child: Text(
                  'BROWSER',
                  style: TextStyle(color: Colors.white, fontSize: 40),
                )),
              ),
            ),
          ),
          Expanded(
            child: InkWell(
              onTap: () {
                Navigator.pushNamed(context, 'advertiser');
              },
              child: Container(
                color: Colors.green,
                child: Center(
                    child: Text(
                  'ADVERTISER',
                  style: TextStyle(color: Colors.white, fontSize: 40),
                )),
              ),
            ),
          ),
        ],
      ),
    );
  }
}

enum DeviceType { advertiser, browser }

class DevicesListScreen extends StatefulWidget {
  const DevicesListScreen({this.deviceType});

  final DeviceType deviceType;

  @override
  _DevicesListScreenState createState() => _DevicesListScreenState();
}

class _DevicesListScreenState extends State<DevicesListScreen> {
  List<Device> devices = [];
  List<Device> connectedDevices = [];
  final nearbyService = NearbyService(serviceType: 'mp-connection');
  StreamSubscription subscription;
  StreamSubscription receivedDataSubscription;

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

    subscription =
        nearbyService.stateChangedSubscription(callback: (devicesList) {
      setState(() {
        devices.clear();
        devices.addAll(devicesList);
        connectedDevices.clear();
        connectedDevices.addAll(devicesList
            .where((d) => d.state == SessionState.connected)
            .toList());
      });
    });

    receivedDataSubscription = nearbyService.dataReceivedSubscription(callback: (data) {
      Fluttertoast.showToast(msg: jsonEncode(data));
    });

    if (widget.deviceType == DeviceType.browser) {
      nearbyService.startBrowsingForPeers();
    } else {
      nearbyService.startAdvertisingPeer();
      nearbyService.startBrowsingForPeers();
    }
    WidgetsBinding.instance.addPostFrameCallback((timeStamp) {});
  }

  @override
  void dispose() {
    subscription?.cancel();
    receivedDataSubscription?.cancel();
    nearbyService.stopBrowsingForPeers();
    nearbyService.startAdvertisingPeer();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.deviceType.toString().substring(11).toUpperCase()),
      ),
      backgroundColor: Colors.white,
      body: ListView.builder(
          itemCount: getItemCount(),
          itemBuilder: (context, index) {
            final device = widget.deviceType == DeviceType.advertiser
                ? connectedDevices[index]
                : devices[index];
            return Container(
              margin: EdgeInsets.all(8.0),
              child: Column(
                children: [
                  Row(
                    children: [
                      Expanded(
                          child: GestureDetector(
                        onTap: () => _onTabItemListener(device),
                        child: Column(
                          children: [
                            Text(device.displayName),
                            Text(
                              getStateName(device.state),
                              style:
                                  TextStyle(color: getStateColor(device.state)),
                            ),
                          ],
                          crossAxisAlignment: CrossAxisAlignment.start,
                        ),
                      )),
                      GestureDetector(
                        onTap: () => _onButtonClicked(device),
                        child: Container(
                          margin: EdgeInsets.symmetric(horizontal: 8.0),
                          padding: EdgeInsets.all(8.0),
                          height: 35,
                          width: 100,
                          color: getButtonColor(device.state),
                          child: Center(
                            child: Text(
                              getButtonStateName(device.state),
                              style: TextStyle(
                                  color: Colors.white,
                                  fontWeight: FontWeight.bold),
                            ),
                          ),
                        ),
                      )
                    ],
                  ),
                  SizedBox(
                    height: 8.0,
                  ),
                  Divider(
                    height: 1,
                    color: Colors.grey,
                  )
                ],
              ),
            );
          }),
    );
  }

  String getStateName(SessionState state) {
    switch (state) {
      case SessionState.notConnected:
        return "disconnected";
      case SessionState.connecting:
        return "waiting";
      default:
        return "connected";
    }
  }

  String getButtonStateName(SessionState state) {
    switch (state) {
      case SessionState.notConnected:
      case SessionState.connecting:
        return "Connect";
      default:
        return "Disconnect";
    }
  }

  Color getStateColor(SessionState state) {
    switch (state) {
      case SessionState.notConnected:
        return Colors.black;
      case SessionState.connecting:
        return Colors.grey;
      default:
        return Colors.green;
    }
  }

  Color getButtonColor(SessionState state) {
    switch (state) {
      case SessionState.notConnected:
      case SessionState.connecting:
        return Colors.green;
      default:
        return Colors.red;
    }
  }

  _onTabItemListener(Device device) {
    if (device.state == SessionState.connected) {
      showDialog(
          context: context,
          builder: (BuildContext context) {
            final myController = TextEditingController();
            return AlertDialog(
              title: Text("Send message"),
              content: TextField(controller: myController),
              actions: [
                FlatButton(
                  child: Text("Cancel"),
                  onPressed: () {
                    Navigator.of(context).pop();
                  },
                ),
                FlatButton(
                  child: Text("Send"),
                  onPressed: () {
                    String jsonData = '{ "message": \" ${myController.text}\" }';
                    nearbyService.sendMessage(device.deviceID, jsonDecode(jsonData));
                    myController.text = '';
                  },
                )
              ],
            );
          });
    }
  }

  int getItemCount() {
    if (widget.deviceType == DeviceType.advertiser) {
      return connectedDevices.length;
    } else {
      return devices.length;
    }
  }

  _onButtonClicked(Device device) {
    switch (device.state) {
      case SessionState.notConnected:
        nearbyService.invitePeer(deviceID: device.deviceID);
        break;
      case SessionState.connected:
        nearbyService.disconnectPeer(deviceID: device.deviceID);
        break;
      case SessionState.connecting:
        break;
    }
  }
}