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import 'package:flutter/material.dart';

class PresManager extends StatefulWidget {
  const PresManager() : super();

  @override
  _PresManagerState createState() => _PresManagerState();
}

class _PresManagerState extends State<PresManager> {
  List<SlideData> test = [
    SlideData(slideTitle: "One"),
    SlideData(slideTitle: "Two"),
    SlideData(slideTitle: "Three"),
  ];
  SlideData? selectedSlide;
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(),
      body: Column(
        children: [
          Flexible(
            child: Row(
              children: [
                Container(
                  width: 200,
                  child: Column(
                    children: [
                      Flexible(
                        child: ReorderableListView(
                          onReorder: (int oldIndex, int newIndex) {
                            test.insert(newIndex, test[oldIndex]);
                            if (oldIndex < newIndex) {
                              test.removeAt(oldIndex);
                            } else {
                              test.removeAt(oldIndex + 1);
                            }
                            setState(() {});
                          },
                          children: test.asMap().entries.map((e) {
                            return ListTile(
                              selectedTileColor:
                                  Theme.of(context).highlightColor,
                              selected: e.value == selectedSlide,
                              key: Key(e.key.toString() + e.value.slideTitle),
                              onTap: () {
                                setState(() {
                                  selectedSlide = e.value;
                                });
                              },
                              title: Padding(
                                padding: const EdgeInsets.only(right: 16.0),
                                child: AspectRatio(
                                  aspectRatio: 16 / 9,
                                  child: Card(
                                    child:
                                        Center(child: Text(e.value.slideTitle)),
                                    elevation: 2,
                                  ),
                                ),
                              ),
                            );
                          }).toList(),
                        ),
                      ),
                      Container(
                        color: Colors.grey,
                        height: 1,
                      ),
                      Container(
                        child: Center(
                          child: ElevatedButton.icon(
                            icon: Icon(Icons.add),
                            label: Padding(
                              padding: const EdgeInsets.only(
                                  top: 10.0, bottom: 10.0),
                              child: Text('Add Slide'),
                            ),
                            onPressed: () {
                              setState(() {
                                test.insert(1, SlideData(slideTitle: 'test'));
                              });
                            },
                          ),
                        ),
                        height: 60,
                      )
                    ],
                  ),
                ),
                Container(
                  width: 1,
                  color: Colors.grey,
                ),
                Container()
              ],
            ),
          ),
        ],
      ),
    );
  }
}

class SlideData {
  String slideTitle;
  SlideData({required this.slideTitle});
}