Hide Show Scrolling FAB

*.kt

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

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