Flutter环境传感器插件environment_sensors的使用

Environment Sensors

Flutter plugin for accessing ambient temperature, relative humidity, ambient light, and barometric pressure sensors of a device.

Install

Add environment_sensors as a dependency in pubspec.yaml. For help on adding as a dependency, view the documentation.

dependencies:
  environment_sensors: ^latest_version

Replace ^latest_version with the latest version of the package. You can find the latest version on the pub.dev page for environment_sensors.

After adding the dependency, run flutter pub get to install it.

Usage

Check for availability of sensors

Before using the sensors, you should check if they are available on the device:

final environmentSensors = EnvironmentSensors();   

var tempAvailable = await environmentSensors.getSensorAvailable(SensorType.AmbientTemperature);
var humidityAvailable = await environmentSensors.getSensorAvailable(SensorType.Humidity);
var lightAvailable = await environmentSensors.getSensorAvailable(SensorType.Light);
var pressureAvailable = await environmentSensors.getSensorAvailable(SensorType.Pressure);

Get sensor stream

You can listen to changes in sensor data by subscribing to the streams provided by the plugin:

final environmentSensors = EnvironmentSensors();

environmentSensors.pressure.listen((pressure) {
  //Pressure in Millibars
  print(pressure.toString());
});

Complete Example Demo

Below is a complete example demo that integrates all the functionalities mentioned above into a simple Flutter application.

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

import 'package:environment_sensors/environment_sensors.dart';

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

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

class _MyAppState extends State<MyApp> {
  bool _tempAvailable = false;
  bool _humidityAvailable = false;
  bool _lightAvailable = false;
  bool _pressureAvailable = false;
  final environmentSensors = EnvironmentSensors();

  @override
  void initState() {
    super.initState();
    // Subscribe to the pressure stream
    environmentSensors.pressure.listen((pressure) {
      print(pressure.toString());
    });
    initPlatformState();
  }

  // Initialize the state of the platform sensors.
  Future<void> initPlatformState() async {
    bool tempAvailable;
    bool humidityAvailable;
    bool lightAvailable;
    bool pressureAvailable;

    tempAvailable = await environmentSensors.getSensorAvailable(SensorType.AmbientTemperature);
    humidityAvailable = await environmentSensors.getSensorAvailable(SensorType.Humidity);
    lightAvailable = await environmentSensors.getSensorAvailable(SensorType.Light);
    pressureAvailable = await environmentSensors.getSensorAvailable(SensorType.Pressure);

    setState(() {
      _tempAvailable = tempAvailable;
      _humidityAvailable = humidityAvailable;
      _lightAvailable = lightAvailable;
      _pressureAvailable = pressureAvailable;
    });
  }

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: const Text('Environment Sensors'),
        ),
        body: Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            (_humidityAvailable)
                ? StreamBuilder<double>(
                    stream: environmentSensors.humidity,
                    builder: (context, snapshot) {
                      if (!snapshot.hasData) return CircularProgressIndicator();
                      return Text(
                          'The Current Humidity is: ${snapshot.data?.toStringAsFixed(2)}%');
                    })
                : Text('No relative humidity sensor found'),
            (_tempAvailable)
                ? StreamBuilder<double>(
                    stream: environmentSensors.temperature,
                    builder: (context, snapshot) {
                      if (!snapshot.hasData) return CircularProgressIndicator();
                      return Text(
                          'The Current Temperature is: ${snapshot.data?.toStringAsFixed(2)}°C');
                    })
                : Text('No temperature sensor found'),
            (_lightAvailable)
                ? StreamBuilder<double>(
                    stream: environmentSensors.light,
                    builder: (context, snapshot) {
                      if (!snapshot.hasData) return CircularProgressIndicator();
                      return Text(
                          'The Current Light is: ${snapshot.data?.toStringAsFixed(2)} lux');
                    })
                : Text('No light sensor found'),
            (_pressureAvailable)
                ? StreamBuilder<double>(
                    stream: environmentSensors.pressure,
                    builder: (context, snapshot) {
                      if (!snapshot.hasData) return CircularProgressIndicator();
                      return Text(
                          'The Current Pressure is: ${snapshot.data?.toStringAsFixed(2)} hPa');
                    })
                : Text('No pressure sensor found'),
          ],
        ),
      ),
    );
  }
}

This demo creates a simple Flutter app that checks for the availability of different environment sensors and displays their current readings in real-time. If a sensor is not available, it will display a message indicating so.