Flutter权限请求插件rx_permissions的使用

rx_permissions 是一个用于在 Flutter 中请求和检查权限的响应式跨平台（iOS 和 Android）API。它依赖于 permission_handler 包。

如何使用

首先，你需要安装 rx_permissions 插件。在 pubspec.yaml 文件中添加以下依赖：

dependencies:
  rx_permissions: ^1.0.0

然后运行 flutter pub get 来获取该包。

请求权限

要请求特定的权限，可以创建一个 RxPermissions 实例，并请求所需的权限列表。

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

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

class MyApp extends StatelessWidget {
  [@override](/user/override)
  Widget build(BuildContext context) {
    return MaterialApp(
      home: MyHomePage(),
    );
  }
}

class MyHomePage extends StatefulWidget {
  [@override](/user/override)
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  RxPermissions rx_permissions = RxPermissions();

  [@override](/user/override)
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text('权限请求示例')),
      body: Center(
        child: ElevatedButton(
          onPressed: () {
            requestPermissions();
          },
          child: Text('请求权限'),
        ),
      ),
    );
  }

  void requestPermissions() async {
    List<Permission> requiredPermission = [Permission.camera, Permission.microphone];

    // 请求权限
    rx_permissions.request(requiredPermission).then((isGranted) {
      if (isGranted) {
        print("权限已授予");
      } else {
        print("权限未被授予");
      }
    });
  }
}

监听权限状态变化

你可以监听权限的状态变化，并根据这些变化执行相应的操作。

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

class MyHomePage extends StatefulWidget {
  [@override](/user/override)
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  RxPermissions rx_permissions = RxPermissions();
  StreamSubscription<List<Permission>> subscription;

  [@override](/user/override)
  void initState() {
    super.initState();
    // 监听权限状态变化
    subscription = rx_permissions.permissions([Permission.camera, Permission.microphone]).listen(onPermissionUpdate);
  }

  [@override](/user/override)
  void dispose() {
    // 订阅取消订阅
    subscription.cancel();
    super.dispose();
  }

  void onPermissionUpdate(List<Permission> result) async {
    List<PermissionResult> permissionResults = await Future.wait(result.map((i) async {
      final granted = await i.isGranted;
      final revoked = await i.isPermanentlyDenied;
      return PermissionResult(i, granted, revoked);
    }));

    // 打印权限结果
    print("权限更新结果: $permissionResults");
  }

  [@override](/user/override)
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text('权限请求示例')),
      body: Center(
        child: ElevatedButton(
          onPressed: () {
            requestPermissions();
          },
          child: Text('请求权限'),
        ),
      ),
    );
  }

  void requestPermissions() async {
    List<Permission> requiredPermission = [Permission.camera, Permission.microphone];

    // 请求权限
    rx_permissions.request(requiredPermission).then((isGranted) {
      if (isGranted) {
        print("权限已授予");
      } else {
        print("权限未被授予");
      }
    });
  }
}

// 定义权限结果类
class PermissionResult {
  final Permission permission;
  final bool granted;
  final bool revoked;

  PermissionResult(this.permission, this.granted, this.revoked);
}