Flutter : How to Automaticallly scroll to end of SingleChildScrollView

Question

I have a SingleChildScrollView, its scrollDirection is set to Horizontal with 5 child widgets placed inside a Row Widget. I want to programmatically scroll to the last widget in the Row and when the last widget is reached(waits 2 seconds) I want to scroll backward.

SingleChildScrollView(
    scrollDirection:Axis.horizontal,
    child:Row(
            children:<Widget>[
                           Widget(),
                           Widget(),
                           Widget(),
                           Widget(),
                           Widget(),  
                         ],
            ), 
    ),

)

Answer 1

You can do it using scroll controller in following way.

 ScrollController _controller;
  @override
  void initState() {
    super.initState();
    _controller = ScrollController();
     WidgetsBinding.instance.addPostFrameCallback((_) {
  _controller
      .animateTo(_controller.position.maxScrollExtent,
          duration: Duration(seconds: 1), curve: Curves.ease)
      .then((value) async {
    await Future.delayed(Duration(seconds: 2));
    _controller.animateTo(_controller.position.minScrollExtent,
        duration: Duration(seconds: 1), curve: Curves.ease);
  });
});
  }

  callMeWidget() {
    return Container(
      height: 100,
      width: 100,
      color: Colors.red,
      margin: EdgeInsets.all(10),
    );
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Container(
        child: SingleChildScrollView(
          controller: _controller,
          scrollDirection: Axis.horizontal,
          child: Row(
            children: <Widget>[
              callMeWidget(),
              callMeWidget(),
              callMeWidget(),
              callMeWidget(),
              callMeWidget(),
            ],
          ),
        ),
      ),
    );
  }

Answer 2

I have a better and more efficient method :

SingleChildScrollView(
    scrollDirection:Axis.horizontal,
    reverse = true;
    child:Row(
            children:<Widget>[
                           Widget(),
                           Widget(),
                           Widget(),
                           Widget(),
                           Widget(),  
                         ],
            ), 
    ),

as simple as that :)

It will scroll to the end as soon as a new widget is added !