@Override
    public void onCreate(@Nullable Bundle savedInstanceState) {
        BoxingConfig config;
        if (savedInstanceState != null) {
            config = savedInstanceState.getParcelable(Boxing.EXTRA_CONFIG);
        } else {
            config = BoxingManager.getInstance().getBoxingConfig();
        }
        setPickerConfig(config);
        onCreateWithSelectedMedias(savedInstanceState, parseSelectedMedias(savedInstanceState, getArguments()));
        super.onCreate(savedInstanceState);

        initCameraPhotoPicker(savedInstanceState);
    }
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