title: RecyclerView with action button as the last element, but It float or stick at bottom when there is many items
body: <p>what I want to implement is a screen where I have RecyclerView that shows a list .. it may has many or few items, when it has many items the Button must be floating and sticky at the end of the screen.</p>
  
  <p>and if the items are few, where there is an empty space in the screen, the button must appear as the final element in the RecyclerView list.</p>
  
  <p>the button is a rectangular raised button with a background. is there any suggestion how to achieve something like this.</p>