Oreo (WRITE EXTERNAL STORAGE) Permission

Question

According to \"developer.android.com\"

If the app targets Android 8.0 (API level 26), the system grants only 
READ_EXTERNAL_STORAGE at that time; however, i         


        

Answer 1

You are correct in adding the permissions to the manifest:

For versions of Lollipop and higher, you need to also request the permissions at runtime. To solve this problem, I created a new method requestAppPermission that I call when the main activity is created. This method runs only for Lollipop and higher, and returns early otherwise:

private void requestAppPermissions() {
    if (android.os.Build.VERSION.SDK_INT < Build.VERSION_CODES.LOLLIPOP) {
        return;
    }

    if (hasReadPermissions() && hasWritePermissions()) {
        return;
    }

    ActivityCompat.requestPermissions(this,
            new String[] {
                    Manifest.permission.READ_EXTERNAL_STORAGE,
                    Manifest.permission.WRITE_EXTERNAL_STORAGE
            }, REQUEST_WRITE_STORAGE_REQUEST_CODE); // your request code
}

private boolean hasReadPermissions() {
    return (ContextCompat.checkSelfPermission(getBaseContext(), Manifest.permission.READ_EXTERNAL_STORAGE) == PackageManager.PERMISSION_GRANTED);
}

private boolean hasWritePermissions() {
    return (ContextCompat.checkSelfPermission(getBaseContext(), Manifest.permission.WRITE_EXTERNAL_STORAGE) == PackageManager.PERMISSION_GRANTED);
}

I call this method in the activity's onCreate:

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    // Other things
    requestAppPermissions();
}

On first load, this will prompt the user to accept permissions.

Then, before you run any code that needs to read and write to storage, you can check these permissions, either by storing the values or running those checks again using methods hasReadPermissions() and hasWritePermissions() defined above.