How to properly hide&show the actionbar using the new design library API?

Question

Background

Suppose I have these elements in the activity:

• actionbar (actually a Toolbar)
• tabs (using TabLayout )
• ViewPager, with fr

Answer 1

this is a nice workaround, but It's still very different than what the Play Store shows:

for each fragment, call something like that:

    recyclerView.addOnScrollListener(new OnScrollListener() {
        @Override
        public void onScrollStateChanged(final RecyclerView recyclerView, final int newState) {
            super.onScrollStateChanged(recyclerView, newState);
            ((MainActivity) getActivity()).onScrollStateChanged(recyclerView, newState);
        }

        @Override
        public void onScrolled(final RecyclerView recyclerView, final int dx, final int dy) {
            super.onScrolled(recyclerView, dx, dy);
            ((MainActivity) getActivity()).onScrolled(recyclerView, dx,dy);
        }
    });

for the hosting activity:

public void onScrollStateChanged(final RecyclerView recyclerView, final int newState) {
    switch (newState) {
        case RecyclerView.SCROLL_STATE_IDLE:
            mAppBarLayout.setExpanded(mLastDy <= 0, true);
            mLastDy = 0;
            break;
    }
}

public void onScrolled(final RecyclerView recyclerView, final int dx, final int dy) {
    mLastDy = dy == 0 ? mLastDy : dy;
}

Still, if anyone knows how to make it work well (using either ListView or RecyclerView for the fragments), just like on the Play-Store and other apps, please write it down.