title: how to show/hide FAB on scroll Recycler view with coordinator parent
body: <p>I have an activity with coordinator layout.inside activity there is a fragment with Recycler view and float button.how can I show/hide float button when Scroll Recycler view and avoid to use fab behavior?!</p>
  <p>in activity layout:
  CoordinatorLayout-----&gt;AppBarLayout----&gt;Toolbar and FrameLayout and Bottom bar view</p>
  <p>in fragment layout:
  RelativeLayout----&gt;Recycler view and float button</p>
  <p>I want to implement something like Google+ home page.
  how can I implement this scenario?</p>
  <hr />
  <h3>Temporary I used this solution for my problem:</h3>
  <p>using coordinator layout of activity by interface in my fragment and show/hide fab with fab behavior ... until I find better solution!!!</p>