Kotlin File(path).walkTopDown() does not find files-CodePudding

The

The code used to "walk through the given directory"

import android.util.Log import java.io.File // path = "/storage/1B10-1D17/ReadTest/" class FileHelper { fun walkTest(path: String){ File(path).walkTopDown().forEach { // println(it) Log.e("walkTest extension", it.extension) if(it.isDirectory){ Log.e("walkTest", "Directory: ${it.name}") }else{ Log.e("walkTest", "File: ${it.name}") } } } }

This will output the following:

E/walkTest extension: E/walkTest: Directory: ReadTest E/walkTest extension: E/walkTest: Directory: SubFolder

In my android manifest file I have the following line and the permission is granted:

<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>

What is the flaw in my code, how can I find the three pdf files stored in these directories?

Update 1/2
As can be seen in the screenshot below, the media access is granted:

If I run the following command (as suggested by dan1st), I get the following output, which shows that pdf file in place:

> adb shell ls /storage/1B10-1D17/ReadTest/ File_1.pdf SubFolder

CodePudding user response：

You generally have no access to arbitrary files on removable storage. This is not changed by READ_EXTERNAL_STORAGE.

Your proposed solution is to use MANAGE_EXTERNAL_STORAGE. Technically, this works, and it is a fine solution for personal-use apps. If your intention is to distribute this app, you will need to file paperwork with Google (and perhaps other app stores) justifying your use of this permission. Stores that disagree with your justification may elect to not distribute your app.

Alternatively, you can use the Storage Access Framework. Use ACTION_OPEN_DOCUMENT_TREE / ActivityResultContracts.OpenDocumentTree and let the user decide where on the user's device (or in the user's cloud storage) the user wants your app to access the user's content. You can then use DocumentFile to walk the document tree to find sub-trees and documents.