@Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        if (REQUEST_CODE_PERMISSION == requestCode) {
            if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                onRequestPermissionSuc(requestCode, permissions, grantResults);
            } else {
                onRequestPermissionError(permissions,
                        new SecurityException("request android.permission.READ_EXTERNAL_STORAGE error."));
            }
        }
    }
to clear all medias the first time(the page number is 0). do some clean work.
boxing/src/main/java/com/bilibili/boxing/AbsBoxingViewFragment.java