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class _ManuallyControlledSliderState extends State<ManuallyControlledSlider> {
  final CarouselController _controller1 = CarouselController();
  final CarouselController _controller2 = CarouselController();
  final CarouselController _controller3 = CarouselController();
  final rng = Random();

  @override
  void initState() {
    super.initState();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
        appBar: AppBar(title: const Text('Manually controlled slider')),
        body: SingleChildScrollView(
          child: Column(
            children: <Widget>[
              CarouselSlider(
                items: imageSliders,
                options: CarouselOptions(height: 100, viewportFraction: 1),
                carouselController: _controller1,
              ),
              CarouselSlider(
                items: imageSliders,
                options: CarouselOptions(height: 100, viewportFraction: 1),
                carouselController: _controller2,
              ),
              CarouselSlider(
                items: imageSliders,
                options: CarouselOptions(height: 100, viewportFraction: 1),
                carouselController: _controller3,
              ),
              Row(
                mainAxisAlignment: MainAxisAlignment.spaceEvenly,
                children: <Widget>[
                  Flexible(
                    child: ElevatedButton(
                      onPressed: () {
                        final index = rng.nextInt(imgList.length);
                        _controller1.animateToPage(index);
                        _controller2.animateToPage(index);
                        _controller3.animateToPage(index);
                      },
                      child: const Text('Random'),
                    ),
                  ),
                  Flexible(
                    child: ElevatedButton(
                      onPressed: () {
                        _controller1.nextPage();
                        _controller2.nextPage();
                        _controller3.nextPage();
                      },
                      child: const Text('→'),
                    ),
                  ),
                ],
              ),
            ],
          ),
        ));
  }
}