flutter_tracker/lib/pages/track_page.dart

import 'package:flutter/material.dart';
import 'package:flutter_blue/flutter_blue.dart';
import 'package:flutter_tracker/utils/app_util.dart';
import 'package:flutter_tracker/views/contact_card.dart';

import 'bluetooth_off_page.dart';

/// Description:
/// Time       : 2021年12月03日 Friday
/// Author     : liuyuqi.gov@msncn
class TrackPage extends StatefulWidget {
  const TrackPage({Key key}) : super(key: key);

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

class _TrackPageState extends State<TrackPage> {
  String testText = '';
  List<dynamic> contactTraces = [];
  List<dynamic> contactTimes = [];
  List<dynamic> contactLocations = [];
  FlutterBlue flutterBlue = FlutterBlue.instance;

  @override
  Widget build(BuildContext context) {
    return StreamBuilder<BluetoothState>(
        stream: FlutterBlue.instance.state,
        initialData: BluetoothState.unknown,
        builder: (c, snapshot) {
          final state = snapshot.data;
          if (state == BluetoothState.on) {
            return buildContent();
          }
          return BluetoothOffPage(state: state);
        });
  }

  Column buildContent() {
    return Column(
      children: <Widget>[
        Expanded(
          child: Padding(
            padding: const EdgeInsets.only(
              left: 25.0,
              right: 25.0,
              bottom: 10.0,
              top: 30.0,
            ),
            child: Container(
              height: 50.0,
              width: double.infinity,
              decoration: BoxDecoration(
                color: Colors.deepPurple[500],
                borderRadius: BorderRadius.circular(20.0),
                boxShadow: const [
                  BoxShadow(
                    color: Colors.black,
                    blurRadius: 4.0,
                    spreadRadius: 0.0,
                    offset: Offset(2.0, 2.0), // shadow direction: bottom right
                  )
                ],
              ),
              child: Row(
                children: const <Widget>[
                  Expanded(
                    child: Image(
                      image: AssetImage('assets/images/corona.png'),
                    ),
                  ),
                  Expanded(
                    flex: 2,
                    child: Text(
                      '附近用户',
                      textAlign: TextAlign.left,
                      style: TextStyle(
                        fontSize: 21.0,
                        color: Colors.white,
                        fontWeight: FontWeight.w500,
                      ),
                    ),
                  )
                ],
              ),
            ),
          ),
        ),
        buildStartButton(),
        Expanded(
          flex: 2,
          child: Padding(
            padding: const EdgeInsets.symmetric(horizontal: 25.0),
            child: ListView.builder(
              itemBuilder: (context, index) {
                return ContactCard(
                  imagePath: 'assets/images/head.jpg',
                  infection: '健康',
                  contactUsername: contactTraces[index],
                  contactTime: contactTimes[index],
                );
              },
              itemCount: contactTraces.length,
            ),
          ),
        ),
      ],
    );
  }

  StreamBuilder<bool> buildStartButton() {
    return StreamBuilder<bool>(
        stream: flutterBlue.isScanning,
        initialData: false,
        builder: (context, snapshot) {
          if (snapshot.data) {
            return Padding(
              padding: EdgeInsets.only(bottom: 200.0),
              child: RaisedButton(
                shape: RoundedRectangleBorder(
                    borderRadius: BorderRadius.circular(20.0)),
                elevation: 5.0,
                color: Colors.red,
                onPressed: () async {
                  startTrack(snapshot.data);
                },
                child: const Text(
                  '停止追踪',
                  style: TextStyle(
                    fontSize: 20.0,
                    fontWeight: FontWeight.bold,
                    color: Colors.white,
                  ),
                ),
              ),
            );
          } else {
            return Padding(
              padding: EdgeInsets.only(bottom: 200.0),
              child: RaisedButton(
                shape: RoundedRectangleBorder(
                    borderRadius: BorderRadius.circular(20.0)),
                elevation: 5.0,
                color: Colors.deepPurple[400],
                onPressed: () async {
                  startTrack(snapshot.data);
                },
                child: const Text(
                  '开始追踪',
                  style: TextStyle(
                    fontSize: 20.0,
                    fontWeight: FontWeight.bold,
                    color: Colors.white,
                  ),
                ),
              ),
            );
          }
        });
  }

  void startTrack(bool flag) async {
    if (flag) {
      flutterBlue.stopScan();
    } else {
      AppUtil.buildToast("正在搜索附近的人...");
      flutterBlue.startScan(timeout: const Duration(seconds: 4));
      //  扫描周围蓝牙设备
      // List<BluetoothService> services = await device.discoverServices();
      var subscription = flutterBlue.scanResults.listen((scanResult) {
        for (ScanResult scan in scanResult) {
          BluetoothDevice device = scan.device;
          print("------------------------------" +
              '${device.name} found! rssi: ${scan.rssi}dBm' +
              device.id.toString());
        }
      });
      // 上传周边设备到服务器

      //  循环对每个设备检测安全性

      //更新结果

    }

    // try {
    //   bool a = await Nearby().startAdvertising(
    //     loggedInUser.email,
    //     strategy,
    //     onConnectionInitiated: null,
    //     onConnectionResult: (id, status) {
    //       print(status);
    //     },
    //     onDisconnected: (id) {
    //       print('Disconnected $id');
    //     },
    //   );
    //
    //   print('ADVERTISING ${a.toString()}');
    // } catch (e) {
    //   print(e);
    // }

    discovery();
    AppUtil.buildToast("追踪用户状态中...");
  }

  void discovery() async {}
}