AppBarLayout.java

   appBarLayout.addOnOffsetChangedListener(new AppBarLayout.OnOffsetChangedListener() {
      boolean isShow = false;
      int scrollRange = -1;

      @Override public void onOffsetChanged(AppBarLayout appBarLayout, int verticalOffset) {
        if (scrollRange == -1) {
          scrollRange = appBarLayout.getTotalScrollRange();
        }
        if (scrollRange + verticalOffset == 0) {
          getSupportActionBar().setTitle(series.title_english);
          isShow = true;
        } else if (isShow) {
          getSupportActionBar().setTitle("");
          isShow = false;
        }
      }
    });