Cannot READ/WRITE on External Storage, even having given Permissions

Gouz :

Running my App on a Huawei Mate 20, the following lines:

    String ext_path = Environment.getExternalStorageDirectory().getAbsolutePath();
    File ext_folder = new File(ext_path);
    System.out.println("Path: " + ext_path + " Dir Check: " + ext_folder.isDirectory() + " Can read: " + ext_folder.canRead());

Return: "Path: /storage/emulated/0 Dir Check: true Can read: false"

However, I have given all permissions and I have also included these in the manifest:

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

Shouldn't canRead() return True? I cannot write or read files. What could be the reason?

I also tried:

    String extStore = System.getenv("EXTERNAL_STORAGE");
    File f_exts = new File(extStore);
    System.out.println(f_exts);
    System.out.println(Arrays.toString(f_exts.listFiles()));

and I get: "EXTERNAL_STORAGE" and "null"

quealegriamasalegre :

you need to explicitly ask the user to grant said permissions. else it wont work in newer android vesions.try adding this in onCreate

ActivityCompat.requestPermissions(MainActivity.this, new String[]{READ_EXTERNAL_STORAGE, WRITE_EXTERNAL_STORAGE},111);

And also

If you are TARGETING Android Q also Environment.getExternalStorageDirectory() no longer leading to an accessible folder, which i think is actually your problem. it is deprecated in favor of Context.getExternalFilesDir(null) which returns a file. that is worth a try as your apps external storage should be something like "/storage/emulated/0/Android/data/com.example.android.YourApp/" and on that one you should have read and write access