Flutter WiFi Direct Plugin

THIS IS MY CODE:

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

import 'package:flutter_p2p/flutter_p2p.dart';
import 'package:flutter_p2p/gen/protos/protos.pb.dart';

class HomePage extends StatefulWidget {
@override
_HomePageState createState() => _HomePageState();
}

class _HomePageState extends State with WidgetsBindingObserver {
@override
void initState() {
super.initState();
_register();
WidgetsBinding.instance.addObserver(this);
}

@override
void dispose() {
WidgetsBinding.instance.removeObserver(this);
super.dispose();
}

@override
void didChangeAppLifecycleState(AppLifecycleState state) {
if (state == AppLifecycleState.resumed) {
_register();
} else if (state == AppLifecycleState.paused) {
_unregister();
}
}

List devices = [];

var _isConnected = false;
var _isHost = false;

List _subscriptions = [];

void _register() async {
if (!await _checkPermission()) {
return;
}
_subscriptions.add(FlutterP2p.wifiEvents.stateChange.listen((change) {
print("stateChange: ${change.isEnabled}");
}));

_subscriptions.add(FlutterP2p.wifiEvents.connectionChange.listen((change) {
  setState(() {
    _isConnected = change.networkInfo.isConnected;
    _isHost = change.wifiP2pInfo.isGroupOwner;
    _deviceAddress = change.wifiP2pInfo.groupOwnerAddress;
  });
  print(
      "connectionChange: ${change.wifiP2pInfo.isGroupOwner}, Connected: ${change.networkInfo.isConnected}");
}));

_subscriptions.add(FlutterP2p.wifiEvents.thisDeviceChange.listen((change) {
  print(
      "deviceChange: ${change.deviceName} / ${change.deviceAddress} / ${change.primaryDeviceType} / ${change.secondaryDeviceType} ${change.isGroupOwner ? 'GO' : '-GO'}");
}));

_subscriptions.add(FlutterP2p.wifiEvents.discoveryChange.listen((change) {
  print("discoveryStateChange: ${change.isDiscovering}");
}));

_subscriptions.add(FlutterP2p.wifiEvents.peersChange.listen((change) {
  print("peersChange: ${change.devices.length}");
  change.devices.forEach((device) {
    print("device: ${device.deviceName} / ${device.deviceAddress}");
  });

  setState(() {
    devices = change.devices;
  });
}));

FlutterP2p.register();

}

void _unregister() {
_subscriptions.forEach((subscription) => subscription.cancel());
FlutterP2p.unregister();
}

P2pSocket _socket;
void _openPortAndAccept(int port) async {
var socket = await FlutterP2p.openHostPort(port);
setState(() {
_socket = socket;
});

var buffer = "";
socket.inputStream.listen((data) {
  var msg = String.fromCharCodes(data.data);
  buffer += msg;
  if (data.dataAvailable == 0) {
    snackBar("Data Received: $buffer");
    socket.writeString("Successfully received: $buffer");
    buffer = "";
  }
});

print("_openPort done");

await FlutterP2p.acceptPort(port);
print("_accept done");

}

var _deviceAddress = "";

_connectToPort(int port) async {
var socket = await FlutterP2p.connectToHost(
_deviceAddress,
port,
timeout: 100000,
);

setState(() {
  _socket = socket;
});

_socket.inputStream.listen((data) {
  var msg = utf8.decode(data.data);
  snackBar("Received from Host: $msg");
});

print("_connectToPort done");

}

Future _checkPermission() async {
if (!await FlutterP2p.isLocationPermissionGranted()) {
await FlutterP2p.requestLocationPermission();
return false;
}
return true;
}

final _scaffoldKey = GlobalKey();

@override
Widget build(BuildContext context) {
return Scaffold(
key: _scaffoldKey,
appBar: AppBar(
title: const Text('Plugin example app 2'),
),
body: Column(
children: [
Text(_isConnected
? "Connected: ${_isHost ? "Host" : "Client"}"
: "Disconnected"),
RaisedButton(
onPressed: () => FlutterP2p.discoverDevices(),
child: Text("Discover Devices"),
),
RaisedButton(
onPressed:
_isConnected && _isHost ? () => _openPortAndAccept(8888) : null,
child: Text("Open and accept data from port 8888"),
),
RaisedButton(
onPressed: _isConnected ? () => _connectToPort(8888) : null,
child: Text("Connect to port 8888"),
),
RaisedButton(
onPressed: _socket != null
? () => _socket.writeString("Hello World")
: null,
child: Text("Send hello world"),
),
RaisedButton(
onPressed: _isConnected ? () => FlutterP2p.removeGroup() : null,
child: Text("Disconnect"),
),
Expanded(
child: ListView(
children: this.devices.map((d) {
return ListTile(
title: Text(d.deviceName),
subtitle: Text(d.deviceAddress),
onTap: () {
print(
"${_isConnected ? "Disconnect" : "Connect"} to device: $_deviceAddress");
return _isConnected
? FlutterP2p.cancelConnect(d)
: FlutterP2p.connect(d);
},
);
}).toList(),
),
),
],
),
);
}

snackBar(String text) {
_scaffoldKey.currentState.showSnackBar(
SnackBar(
content: Text(text),
duration: Duration(seconds: 2),
),
);
}
}

ERROR OCCURED TO ME:

A problem occurred configuring project ':flutter_p2p'.

Could not resolve all artifacts for configuration ':flutter_p2p:classpath'.
Could not download kotlin-compiler-embeddable.jar (org.jetbrains.kotlin:kotlin-compiler-embeddable:1.2.71)
> Could not get resource 'jcenter.bintray.com/org/jetbrains/...'.
> Premature end of Content-Length delimited message body (expected: 29106171; received: 27524912
Could not get unknown property 'android' for project ':flutter_p2p' of type org.gradle.api.Project.

Dear sir thank you for providing help on wifi direct and p2p connection . i have issue in transferring data like image videos and some else format over the socket basically how the data is going to be encoded and decoded at server and client side please help

Can you please provide with sample code because discover devices showing empty List everytime.

I've seen it. Very nice Library thank you. But the minimum API level that it supports is API level 23. What about for API level below 23?

how I can send and receive files like images, docs, etc. using p2p

AFAIK, iOS does not support Wi-Fi direct. Link: forums.developer.apple.com/thread/...

Hello Sir , i was working with your package provided on flutterp2p i was having a query that is can i send files (jpg , png , pdf etc.) using this package. please help
thank you

please give solution to me , my source code is below

Sir, please provide a manual how to use the plugin .