Flutter中如何阻止或检测带音频的屏幕录制？

针对你遇到的flutter_windowmanager仅能阻止屏幕内容但无法拦截音频录制的问题，需要针对Android和iOS分别通过原生层API实现检测与拦截，以下是具体方案：

Android 端实现 #

1. 检测屏幕录制状态并处理音频 #

Android 10（API 29）及以上可通过AudioManager监听音频捕获状态，结合MethodChannel实现Flutter与原生的通信，在录屏触发时暂停/恢复应用音频：

原生代码（Kotlin）

class MainActivity : FlutterActivity() {
    private val CHANNEL = "com.app.screen_capture/audio"
    private var isScreenRecording = false

    override fun configureFlutterEngine(flutterEngine: FlutterEngine) {
        super.configureFlutterEngine(flutterEngine)
        // 注册MethodChannel处理Flutter调用
        MethodChannel(flutterEngine.dartExecutor.binaryMessenger, CHANNEL).setMethodCallHandler { call, result ->
            when (call.method) {
                "isScreenRecording" -> result.success(isScreenRecording)
                else -> result.notImplemented()
            }
        }

        // 监听音频捕获状态，判断是否在录屏
        val audioManager = getSystemService(AUDIO_SERVICE) as AudioManager
        audioManager.registerAudioPlaybackCallback(object : AudioManager.AudioPlaybackCallback() {
            override fun onPlaybackConfigChanged(configs: MutableList<AudioPlaybackConfiguration>) {
                super.onPlaybackConfigChanged(configs)
                isScreenRecording = configs.any { it.clientType == AudioPlaybackConfiguration.CLIENT_TYPE_REMOTE_SUBMIX }
                // 通知Flutter端录屏状态变化
                MethodChannel(flutterEngine.dartExecutor.binaryMessenger, CHANNEL)
                    .invokeMethod("onScreenRecordingChanged", isScreenRecording)
            }
        }, Handler(Looper.getMainLooper()))
    }
}

Flutter 端代码

import 'package:flutter/services.dart';

class ScreenAudioGuard {
  static const MethodChannel _channel = MethodChannel('com.app.screen_capture/audio');
  static bool _isRecording = false;

  static Future<bool> get isScreenRecording async {
    final bool result = await _channel.invokeMethod('isScreenRecording');
    return result;
  }

  static void init() {
    _channel.setMethodCallHandler((call) async {
      if (call.method == 'onScreenRecordingChanged') {
        _isRecording = call.arguments as bool;
        // 录屏状态变化时处理音频
        if (_isRecording) {
          // 暂停应用内所有音频播放
          // 例如调用音频播放器的pause()方法
        } else {
          // 恢复音频播放
        }
      }
    });
  }
}

2. 强制音频不被捕获 #

可在原生层设置音频属性，让音频仅输出到扬声器且禁止被录制：

val audioAttributes = AudioAttributes.Builder()
    .setUsage(AudioAttributes.USAGE_MEDIA)
    .setContentType(AudioAttributes.CONTENT_TYPE_MUSIC)
    .setFlags(AudioAttributes.FLAG_AUDIBILITY_ENFORCED)
    .build()
val audioManager = getSystemService(AUDIO_SERVICE) as AudioManager
audioManager.setAudioAttributes(audioAttributes)

iOS 端实现 #

iOS 系统提供UIScreen.capturedDidChangeNotification通知监听录屏状态，同样通过MethodChannel实现跨端通信：

原生代码（Swift） #

import UIKit
import Flutter

class MainViewController: FlutterViewController {
    private let CHANNEL = "com.app.screen_capture/audio"
    private var isScreenRecording = false

    override func viewDidLoad() {
        super.viewDidLoad()
        let channel = FlutterMethodChannel(name: CHANNEL, binaryMessenger: flutterEngine!.binaryMessenger)
        channel.setMethodCallHandler { [weak self] call, result in
            guard let self = self else { return }
            switch call.method {
            case "isScreenRecording":
                result.success(self.isScreenRecording)
            default:
                result.notImplemented()
            }
        }

        // 监听屏幕录制状态变化
        NotificationCenter.default.addObserver(
            self,
            selector: #selector(screenCaptureChanged),
            name: UIScreen.capturedDidChangeNotification,
            object: nil
        )
    }

    @objc private func screenCaptureChanged() {
        isScreenRecording = UIScreen.main.isCaptured
        let channel = FlutterMethodChannel(name: CHANNEL, binaryMessenger: flutterEngine!.binaryMessenger)
        channel.invokeMethod("onScreenRecordingChanged", arguments: isScreenRecording)
    }
}

Flutter 端代码 #

复用Android端的ScreenAudioGuard类即可，通过监听回调处理音频暂停/恢复逻辑。

替代方案 #

如果无需保留应用音频，可在检测到录屏时直接静音应用音频输出，避免被录屏捕获。

内容的提问来源于stack exchange，提问作者Imarana