IssueTracker

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Android build and device used:
Google Pixel 3a XL - R(RPPP1.200123.017)

Expected output:
I would like to be able to pass a file path to an external library, in this case, FFmpeg. Once again quoting the docs-

Starting in Android 11, apps that have the READ_EXTERNAL_STORAGE permission can read a device's media files using direct file paths and native libraries. This new capability allows your app to work more smoothly with third-party media libraries.

Current output:
There is no API (I could find), to even receive a file path from media store.

What I have tried:

• Retrieving the path directly from the Uri (I know this is not recommended):

String path = data.getData().getPath();

Result (As I suspected):

/document/B1DE-1114:VID_25060906_162219.mp4: No such file or directory

• Using proc protocol:

ParcelFileDescriptor parcelFileDescriptor = null;
try {
    parcelFileDescriptor = getContentResolver().openFileDescriptor(data.getData(), "r");

} catch (FileNotFoundException e) {
    e.printStackTrace();
}
int fd = 0;
try {
    fd = parcelFileDescriptor.getFd();
} catch (Exception e) {
    e.printStackTrace();
}
//Process process = new Process()
int pid = Process.myPid();
String path = "/proc/" + pid + "/fd/" + fd;

Result:
/proc/9751/fd/68: Permission denied

• I have also tried accessing the data column, which was deprecated in 29, just to make sure. But I was not able to retrieve the path.

The docs state that we can pass a file path to a native library, but I could not find a way of doing this.

I tried again and I was able to get the path using the data column.

But, in the documentation, it says that we should not use the data column as it is deprecated - https://developer.android.com/reference/android/provider/MediaStore.MediaColumns#DATA

Is it save to keep using the data column even if it is deprecated? Will there be a new API made available replacing the data column?

Also, once again quoting the docs - https://developer.android.com/preview/privacy/storage#scoped-storage

After you update your app to target Android 11, you cannot use requestLegacyExternalStorage to opt out of scoped storage.

So, does this mean that we can remove requestLegacyExternalStorage when targeting Android 11 and we will still be able to read file paths on Android 10? Or should we keep requestLegacyExternalStorage in our manifest when targeting Android 11?

Re #8: Do keep requestLegacyExternalStorage in the manifest if you need legacy storage on Q devices. It will be ignored on R devices once you target R. We are improving the documentation on this.

Re DATA column: will publish more guidance on this soon

#10 anyway to have some insight about https://issuetracker.google.com/issues/148189415 ?

#14 - requestLegacyExternalStorage is only necessary for Android 10(Q). On Android R, this will be ignored - file access is once again available in Android R, so you can leave requestLegacyExternalStorage in your Manifest if you want to use legacy storage on Android Q devices.

Re 10#: The documentation has not yet been updated, nor has the clarification about the data column. Android R release is near and developers want to get ready for the release. Can you please confirm when this will be updated?

Sorry about the delay. The detailed guide is still in the works. However I can summarize the recommendation to unblock you:

Don't use DATA column for inserting or updating into Media Store - use DISPLAY_NAME and RELATIVE_PATH for this. For existing Media Store entries if the file exists on disk DATA column will have a valid file path, which can be used with java File api or NDK library (fopen etc). Apps should however be prepared to handle any file I/O errors from these operations and should not assume file is always available.

Hope this helps