Android Q (10) ask permission to get access all storage. Scoped storage

Question

In Android 10 apps that need to access storage need to ask permission to access a concrete path. But apps like file explorer can ask permission for access to the root storage and gain permission to read/write to all storage. That is what I am trying to do.

According to Android we must use ACTION_OPEN_DOCUMENT_TREE for this. The problem I have is that everything seems correct, but the permission is not granted to the app.

  private void askAndroid10Perm()
    {
        Intent intent = new Intent(Intent.ACTION_OPEN_DOCUMENT_TREE);
        intent.addFlags(
                Intent.FLAG_GRANT_READ_URI_PERMISSION
                        | Intent.FLAG_GRANT_WRITE_URI_PERMISSION
                        | Intent.FLAG_GRANT_PERSISTABLE_URI_PERMISSION
                        | Intent.FLAG_GRANT_PREFIX_URI_PERMISSION);
        startActivityForResult(intent, REQUEST_CODE_OPEN_DOCUMENT_TREE);
    }

Here the user can see Android file tree and, with main storage selected, click to grant permission. "It will allow - app name - to have full access to all files currently store under this location, and any future content stored here" -> Allow

Then:

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    switch (requestCode) {
        case REQUEST_CODE_OPEN_DOCUMENT_TREE:
            if (resultCode == Activity.RESULT_OK) {
                Uri treeUri = data.getData();
                int takeFlags = data.getFlags();
                takeFlags &= (Intent.FLAG_GRANT_READ_URI_PERMISSION |
                        Intent.FLAG_GRANT_WRITE_URI_PERMISSION);

                if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {

                    Log.i("TAG", "takePersistableUriPermission: " + treeUri);
                    this.getContentResolver().takePersistableUriPermission(treeUri, takeFlags);

                }

            }
    }
}

Log:

takePersistableUriPermission: content://com.android.externalstorage.documents/tree/primary%3A

Then the app will still not have permission to access to root.

open failed: EACCES (Permission denied)

Of course I have:

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

Granted by the user.

Answer 1

Scoped Storage not accept by PlayConsole so now its not Worked.

For Work Android 11 or Up.

in Android Q If you giving permission and its granted or not working so go to Manifest and add

<application
    android:allowBackup="true"
    android:icon="@mipmap/ic_launcher"
    android:requestLegacyExternalStorage="true" //Add this Line
    android:label="@string/app_name">

---------<Activity, Sevices or Recivers>----------

</application>

and in build.gradle

compileSdkVersion 29 //SDK Version don't update to 30
defaultConfig {
    applicationId 'com.example.application'
    minSdkVersion 16
    targetSdkVersion 29 //SDK Version don't update to 30
    versionCode 1
    versionName "1.0"
    testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
}