How to hide floating action button in the top recycler view and show when scroling down?

Question

I'm trying to only display a floating action button when the Recycler View is scrolling down and hide when position is at the very top. I'm sorry my english is very bad

Answer 1

recyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
    @Override
    public void onScrolled(RecyclerView recyclerView, int dx,int dy){
        super.onScrolled(recyclerView, dx, dy);

        if (dy >0) {
            // Scroll Down
            if (fab.isShown()) {
                fab.hide();
            }
        }
        else if (dy <0) {
            // Scroll Up
            if (!fab.isShown()) {
                fab.show();
            }
        }
     }
})

Answer 2

here what you can do to identify scrolling state

 recyclerview.addOnScrollListener(new RecyclerView.OnScrollListener() {
        @Override
        public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
            super.onScrollStateChanged(recyclerView, newState);

            if (!recyclerView.canScrollVertically(1) && newState==RecyclerView.SCROLL_STATE_IDLE) {

               //do what you want if recyclerview scrolled to bottom
            }else{

                //do what you want if recyclerview not scrolled to bottom
            }
        }
    });

Answer 3

Add scroll listener for recylerview & hide fab when scrolling

 fun hideFabWhenScroll(fab: FloatingActionButton, recyclerView: RecyclerView){
    recyclerView.addOnScrollListener(object : RecyclerView.OnScrollListener() {
        override fun onScrolled(recyclerView: RecyclerView, dx: Int, dy: Int) {
            if (dy > 0 || dy < 0 && fab.isShown) {
                fab.hide()
            }
        }

        override fun onScrollStateChanged(recyclerView: RecyclerView, newState: Int) {
            if (newState == RecyclerView.SCROLL_STATE_IDLE) {
                fab.show()
            }

            super.onScrollStateChanged(recyclerView, newState)
        }
    })
}