Will it be a good practice to call the getExternalFilesDir() method inside the Dispatchers.IO of coroutine?

Question

In the production app we have seen few cases where getExternalFilesDir(Environment.DIRECTORY_DOWNLOADS)?.absolutePath method call is causing the ANR issue.

So to solve this issue can we utilize the Coroutine?

something like this

lifecycleScope.launch {
    val envPath = withContext(Dispatchers.IO) { getExternalFilesDir(Environment.DIRECTORY_DOWNLOADS)?.absolutePath.orEmpty() }
    // code, which will utilize the envPath
  }

as the getExternalFilesDir() method is the part of ContextWrapper so will it create any problem if we will call it inside a different thread using the coroutine?

Answer 1

getExternalFilesDir uses android.os.storage.StorageManager which is Android system service. StorageManager is executed in a separate process, so it may block for a large of time.

Kotlin Coroutines: Deep Dive (Dispatchers chapter) recommends using Dispatchers.IO for code that may block a thread.

To sum up, it totally makes sense to use background thread for getExternalFilesDir.