final compressProgress$ = ObservableBuilder<double>();  final _channel = const MethodChannel('video_compress');
  @protected  void initProcessCallback() {    _channel.setMethodCallHandler(_progressCallback);  }
  MethodChannel get channel => _channel;
  bool _isCompressing = false;
  bool get isCompressing => _isCompressing;
  @protected  void setProcessingStatus(bool status) {    _isCompressing = status;  }
  Future<void> _progressCallback(MethodCall call) async {    switch (call.method) {      case 'updateProgress':        final progress = double.tryParse(call.arguments.toString());        if (progress != null) compressProgress$.next(progress);        break;    }  }

封装请求方法，传递压缩参数final jsonStr = await _invoke<String>('compressVideo', {  'path': path,  'quality': quality.index,  'deleteOrigin': deleteOrigin,  'startTime': startTime,  'duration': duration,  'includeAudio': includeAudio,  'frameRate': frameRate,});

const CHANNEL_NAME = "video_compress";
private methodChannel: MethodChannel | null = null;  private applicationContext: Context | null = null;  private ability: UIAbility | null = null;  private unity: Unity | null = null;  private videoCompress: VideoCompress | null = null;
  onAttachedToAbility(binding: AbilityPluginBinding): void {    Log.i(TAG, "onAttachedToAbility");    this.ability = binding.getAbility();    this.unity = new Unity(this.ability.context);    this.videoCompress = new VideoCompress(this.ability.context);  }
  onDetachedFromAbility(): void {    Log.i(TAG, "onDetachedFromAbility");    this.ability = null;  }
  onAttachedToEngine(binding: FlutterPluginBinding): void {    this.applicationContext = binding.getApplicationContext();    this.methodChannel = new MethodChannel(binding.getBinaryMessenger(), CHANNEL_NAME);    this.methodChannel.setMethodCallHandler(this);  }
  onDetachedFromEngine(binding: FlutterPluginBinding): void {    this.applicationContext = null;    this.methodChannel?.setMethodCallHandler(null);    this.methodChannel = null;  }    onMethodCall(call: MethodCall, result: MethodResult): void {    Log.d(TAG, "call: " + call.method)
    try {      switch (call.method) {        case 'compressVideo': {          const path = call.argument("path") as string;          const quality = call.argument("quality") as number;          const deleteOrigin = call.argument("deleteOrigin") as boolean;          const startTime = call.argument("startTime") as number;          const duration = call.argument("duration") as number;
          Log.d(TAG, JSON.stringify({            path,            quality,            deleteOrigin,            startTime,            duration          }))          Log.d(TAG, path)
          let includeAudio = call.argument("includeAudio") as boolean | undefined;          if (includeAudio === undefined) {            includeAudio = true;          }
          let frameRate = call.argument("frameRate") as number | undefined;          if (frameRate === undefined) {            frameRate = 30;          }
          const tempDir = this.applicationContext!.tempDir;          const out: string = dayjs().format('YYYY-MM-DD HH-mm-ss');          const destPath: string = tempDir + "/VID_" + out + ".mp4";
          Log.d(TAG, destPath)
          this.methodChannel?.invokeMethod("updateProgress", 1)          this.videoCompress?.compress(path, quality).then(out => {            if (deleteOrigin) {              fs.unlinkSync(path);            }            this.unity?.getMediaInfoJson(out).then((json) => {              Log.d(TAG, JSON.stringify(json))              json['isCancel'] = false;              this.methodChannel?.invokeMethod("updateProgress", 100)              result.success(JSON.stringify(json))            })          })          break;        }        default:          result.notImplemented()      }    } catch (err) {      result.error("Name not found", err.message, null)    }  }