private void checkPermissionAndLoad() {
        try {
            if (!BoxingBuilderConfig.TESTING && Build.VERSION.SDK_INT >= Build.VERSION_CODES.M
                    && ContextCompat.checkSelfPermission(getActivity(), STORAGE_PERMISSIONS[0]) != PERMISSION_GRANTED
                    && ContextCompat.checkSelfPermission(getActivity(), STORAGE_PERMISSIONS[1]) != PERMISSION_GRANTED) {
                requestPermissions(STORAGE_PERMISSIONS, REQUEST_CODE_PERMISSION);
            } else {
                startLoading();
            }
        } catch (IllegalArgumentException | IllegalStateException e) {
            onRequestPermissionError(STORAGE_PERMISSIONS, e);
        }

    }
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