Flutter屏幕亮度控制插件screen_brightness_util的使用

screen_brightness_util 是一个Flutter插件，用于配置和监控屏幕亮度。本文将详细介绍如何使用该插件来获取、设置和监听屏幕亮度的变化。

Getting Started

Get Brightness

要获取当前屏幕的亮度，可以使用 getBrightness 方法：

final ScreenBrightnessUtil _screenBrightnessUtil = ScreenBrightnessUtil();
double brightness = await _screenBrightnessUtil.getBrightness();
if(brightness == -1) {
  debugPrint("Oops... something wrong!");
}

Set Brightness

要设置屏幕亮度，可以使用 setBrightness 方法：

double brightness = 0.5;
final ScreenBrightnessUtil _screenBrightnessUtil = ScreenBrightnessUtil();
bool success = await _screenBrightnessUtil.setBrightness(brightness);

Listen Brightness Change

要监听屏幕亮度的变化，可以使用 getBrightnessChangeStream 方法并订阅其流：

final ScreenBrightnessUtil _screenBrightnessUtil = ScreenBrightnessUtil();
StreamSubscription ss = _screenBrightnessUtil.getBrightnessChangeStream().listen((brightness) {
  debugPrint("brightness:$brightness");
});

// 记得在不再需要时取消订阅
ss.cancel();

示例代码

以下是一个完整的示例应用，展示了如何使用 screen_brightness_util 插件来获取、设置和监听屏幕亮度的变化：

import 'dart:async';

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

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

class MyApp extends StatefulWidget {
  const MyApp({Key? key}) : super(key: key);

  @override
  State<MyApp> createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
  late final ScreenBrightnessUtil _screenBrightnessUtil = ScreenBrightnessUtil();
  late StreamSubscription ss;
  String _info = "";
  double _sliderBrightness = 0;

  @override
  void initState() {
    // 监听屏幕亮度变化
    ss = _screenBrightnessUtil.getBrightnessChangeStream().listen((brightness) {
      _updateInfo(brightness);
    });

    // 获取当前屏幕亮度
    _screenBrightnessUtil.getBrightness().then((brightness) {
      _updateInfo(brightness);
    });

    super.initState();
  }

  @override
  void dispose() {
    // 取消订阅
    ss.cancel();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: const Text('Plugin example app'),
        ),
        body: Column(
          mainAxisSize: MainAxisSize.min,
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            const SizedBox(height: 36),
            Row(
              children: [
                const SizedBox(width: 24),
                Text(
                  _info,
                  style: const TextStyle(fontSize: 16),
                ),
              ],
            ),
            const SizedBox(height: 16),
            Slider(
              value: _sliderBrightness,
              onChanged: (setBrightness) {
                _screenBrightnessUtil.setBrightness(setBrightness);
                setState(() {
                  _sliderBrightness = setBrightness;
                });
              },
            ),
          ],
        ),
      ),
    );
  }

  void _updateInfo(double brightness) {
    setState(() {
      bool error = brightness < 0;
      if (error) {
        _info = "OOPS, something wrong!";
        return;
      } else {
        _info = "Brightness: $brightness";
      }
      _sliderBrightness = brightness;
    });
  }
}

说明

1. 初始化：在 initState 方法中，我们订阅了屏幕亮度变化的流，并获取了当前的屏幕亮度。
2. 更新信息：_updateInfo 方法用于更新屏幕亮度的信息，并设置滑块的值。
3. 滑块控件：使用 Slider 控件来调整屏幕亮度，并在滑块值改变时调用 setBrightness 方法。
4. 清理：在 dispose 方法中取消订阅，防止内存泄漏。

通过以上步骤，你可以轻松地在Flutter应用中实现屏幕亮度的控制和监控。希望这篇文章对你有所帮助！