flutter - Display arrow indicator if list is scrollable

Question

I have an horizontal SingleChildScrollView widget with variable amount of different buttons. I want to display button with right arrow only when there is too much buttons to show all on screen. I want to avoid situation when someone could dont know about more buttons hidden behind right edge of the screen.

How to achieve this?

Container(
 height: iconsBarHeight,
 color: Theme.of(context).scaffoldBackgroundColor,
 padding: const EdgeInsets.fromLTRB(16, 16, 8, 0),
 child: SingleChildScrollView(
  scrollDirection: Axis.horizontal,
  child: Row(
   crossAxisAlignment: CrossAxisAlignment.start,
   children: [
    Button2(),
    Button4(),
    Button1(),
    Button6(),
    Button7(),
    Button3(),
    Button2(),
   ],
  ),
 ),
);

Answer 1

you can add ScrollControlller to SingleChildScrollView, and get the max extent of it. If max extent is greater than width of screen, then show the button.

scrollController.position.maxScrollExtent