Flutter设备传感器访问插件flutter_sensors的使用

flutter_sensors 是一个简单的传感器事件监听插件，适用于Flutter（Android和iOS）。以下是详细的使用指南。

安装

首先在您的项目中添加插件。将以下行添加到 pubspec.yaml 文件中的 dependencies 下：

dependencies:
  flutter_sensors: ^1.0.1

然后导入依赖项：

import 'package:flutter_sensors/flutter_sensors.dart';

iOS配置

您需要在 ios/Runner 文件夹中的 Info.plist 文件内添加以下键值对：

<key>NSMotionUsageDescription</key>
<string>A reason to get the permission</string>

Android配置

为了使用步数计数器，您需要在 AndroidManifest.xml 中添加以下权限：

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

如何使用

您可以为特定的传感器注册一个新的监听器。例如，监听加速度计的数据：

final stream = await SensorManager().sensorUpdates(
        sensorId: Sensors.ACCELEROMETER,
        interval: Sensors.SENSOR_DELAY_GAME,
      );
_accelSubscription = stream.listen((sensorEvent) {
        setState(() {
          _accelData = sensorEvent.data;
        });
      });

您还可以检查特定传感器是否可用：

bool accelerometerAvailable =
        await SensorManager().isSensorAvailable(Sensors.ACCELEROMETER);

记得在使用完传感器更新后取消 StreamSubscriptions：

_accelSubscription.cancel();

Android Only

您可以直接提供传感器的ID，而无需使用 Sensors 类。例如，注册一个监听 TYPE_LIGHT 传感器的监听器：

int TYPE_LIGHT = 5; // TYPE_LIGHT is equals to 5
// Checking if is available.
bool isAvailable = await SensorManager().isSensorAvailable(TYPE_LIGHT);
// Initialize a stream to receive the updates.
final stream = await SensorManager().sensorUpdates(sensorId: TYPE_LIGHT);
_lightSubscription = stream.listen((sensorEvent) {
        setState(() {
          _lightData = sensorEvent.data;
        });
      });
// Cancel the stream after using it.
_lightSubscription.cancel();

其他传感器ID可以从 这里 获取。

示例代码

下面是一个完整的示例应用，展示了如何使用 flutter_sensors 插件来访问加速度计和陀螺仪数据，并显示这些数据。

import 'dart:async';

import 'package:flutter/material.dart';
import 'package:flutter_sensors/flutter_sensors.dart';

void main() => runApp(MyApp());

class MyApp extends StatefulWidget {
  @override
  _MyAppState createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
  bool _accelAvailable = false;
  bool _gyroAvailable = false;
  List<double> _accelData = List.filled(3, 0.0);
  List<double> _gyroData = List.filled(3, 0.0);
  StreamSubscription? _accelSubscription;
  StreamSubscription? _gyroSubscription;

  @override
  void initState() {
    _checkAccelerometerStatus();
    _checkGyroscopeStatus();
    super.initState();
  }

  @override
  void dispose() {
    _stopAccelerometer();
    _stopGyroscope();
    super.dispose();
  }

  void _checkAccelerometerStatus() async {
    await SensorManager()
        .isSensorAvailable(Sensors.ACCELEROMETER)
        .then((result) {
      setState(() {
        _accelAvailable = result;
      });
    });
  }

  Future<void> _startAccelerometer() async {
    if (_accelSubscription != null) return;
    if (_accelAvailable) {
      final stream = await SensorManager().sensorUpdates(
        sensorId: Sensors.ACCELEROMETER,
        interval: Sensors.SENSOR_DELAY_FASTEST,
      );
      _accelSubscription = stream.listen((sensorEvent) {
        setState(() {
          _accelData = sensorEvent.data;
        });
      });
    }
  }

  void _stopAccelerometer() {
    if (_accelSubscription == null) return;
    _accelSubscription?.cancel();
    _accelSubscription = null;
  }

  void _checkGyroscopeStatus() async {
    await SensorManager().isSensorAvailable(Sensors.GYROSCOPE).then((result) {
      setState(() {
        _gyroAvailable = result;
      });
    });
  }

  Future<void> _startGyroscope() async {
    if (_gyroSubscription != null) return;
    if (_gyroAvailable) {
      final stream =
          await SensorManager().sensorUpdates(sensorId: Sensors.GYROSCOPE);
      _gyroSubscription = stream.listen((sensorEvent) {
        setState(() {
          _gyroData = sensorEvent.data;
        });
      });
    }
  }

  void _stopGyroscope() {
    if (_gyroSubscription == null) return;
    _gyroSubscription?.cancel();
    _gyroSubscription = null;
  }

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: const Text('Flutter Sensors Example'),
        ),
        body: Container(
          padding: EdgeInsets.all(16.0),
          alignment: AlignmentDirectional.topCenter,
          child: Column(
            children: <Widget>[
              Text(
                "Accelerometer Test",
                textAlign: TextAlign.center,
              ),
              Text(
                "Accelerometer Enabled: $_accelAvailable",
                textAlign: TextAlign.center,
              ),
              Padding(padding: EdgeInsets.only(top: 16.0)),
              Text(
                "[0](X) = ${_accelData[0]}",
                textAlign: TextAlign.center,
              ),
              Padding(padding: EdgeInsets.only(top: 16.0)),
              Text(
                "[1](Y) = ${_accelData[1]}",
                textAlign: TextAlign.center,
              ),
              Padding(padding: EdgeInsets.only(top: 16.0)),
              Text(
                "[2](Z) = ${_accelData[2]}",
                textAlign: TextAlign.center,
              ),
              Padding(padding: EdgeInsets.only(top: 16.0)),
              Row(
                mainAxisAlignment: MainAxisAlignment.center,
                children: <Widget>[
                  MaterialButton(
                    child: Text("Start"),
                    color: Colors.green,
                    onPressed: _accelAvailable ? () => _startAccelerometer() : null,
                  ),
                  Padding(
                    padding: EdgeInsets.all(8.0),
                  ),
                  MaterialButton(
                    child: Text("Stop"),
                    color: Colors.red,
                    onPressed: _accelAvailable ? () => _stopAccelerometer() : null,
                  ),
                ],
              ),
              Padding(padding: EdgeInsets.only(top: 16.0)),
              Text(
                "Gyroscope Test",
                textAlign: TextAlign.center,
              ),
              Text(
                "Gyroscope Enabled: $_gyroAvailable",
                textAlign: TextAlign.center,
              ),
              Padding(padding: EdgeInsets.only(top: 16.0)),
              Text(
                "[0](X) = ${_gyroData[0]}",
                textAlign: TextAlign.center,
              ),
              Padding(padding: EdgeInsets.only(top: 16.0)),
              Text(
                "[1](Y) = ${_gyroData[1]}",
                textAlign: TextAlign.center,
              ),
              Padding(padding: EdgeInsets.only(top: 16.0)),
              Text(
                "[2](Z) = ${_gyroData[2]}",
                textAlign: TextAlign.center,
              ),
              Padding(padding: EdgeInsets.only(top: 16.0)),
              Row(
                mainAxisAlignment: MainAxisAlignment.center,
                children: <Widget>[
                  MaterialButton(
                    child: Text("Start"),
                    color: Colors.green,
                    onPressed: _gyroAvailable ? () => _startGyroscope() : null,
                  ),
                  Padding(
                    padding: EdgeInsets.all(8.0),
                  ),
                  MaterialButton(
                    child: Text("Stop"),
                    color: Colors.red,
                    onPressed: _gyroAvailable ? () => _stopGyroscope() : null,
                  ),
                ],
              ),
            ],
          ),
        ),
      ),
    );
  }
}

这个示例应用展示了如何使用 flutter_sensors 插件来访问和显示加速度计和陀螺仪的数据。希望这对您有所帮助！