遇到一个没有直接给进度监听回调的库怎么办呢？

如题，遇到一个没有直接给进度监听回调的库怎么办呢？ Android Jetpack Media3库：Android Jetpack Media3

已知条件：

val progressHolder = ProgressHolder()  
// 返回一个状态  
val progressState = transformer.getProgress(progressHolder)  
// 返回当前的进度  
val progress = progressHolder.progress

实现方式：

fun setProgressListener(transformer: Transformer, block: (progress: Int) -> Unit) {  
    val progressHolder = ProgressHolder()  
    viewModelScope.launch {  
        while (isActive) {  
            val progressState = transformer.getProgress(progressHolder)  
            when (progressState) {  
                Transformer.PROGRESS_STATE_AVAILABLE -> {  
                    val progress = progressHolder.progress  
                    block.invoke(progress)  
                }  
  
                Transformer.PROGRESS_STATE_UNAVAILABLE -> {  
                    cancel()  
                }  
  
                Transformer.PROGRESS_STATE_NOT_STARTED -> {  
                    // Nothing to do.  
                }  
  
                Transformer.PROGRESS_STATE_WAITING_FOR_AVAILABILITY -> {  
                    Timber.d("视频处理等待进度可用")  
                }  
            }  
            delay(1000)  
        }  
    }  
}