main.dart

import 'package:flutter/material.dart';

import 'todo_class.dart';

class TodoScreen extends StatefulWidget {
  @override
  _TodoScreenState createState() => _TodoScreenState();
}

class _TodoScreenState extends State<TodoScreen> {
  List<ToDo> tasksTodo;
  final GlobalKey<AnimatedListState> _listKey = GlobalKey();
  final ToDoDatabase database = ToDoDatabase();

  void showTextfield() {
    String titleInput;
    showModalBottomSheet(
        context: context,
        builder: (context) => Padding(
              padding: MediaQuery.of(context).viewInsets,
              child: Padding(
                  padding: const EdgeInsets.all(8.0),
                  child: TextField(
                    autofocus: true,
                    decoration: InputDecoration(
                        suffixIcon: IconButton(
                            icon: Icon(Icons.send),
                            onPressed: () {
                              Navigator.pop(context);
                              _insertSingleItem('$titleInput');
                            })),
                    onChanged: (String value) {
                      setState(() {
                        titleInput = value;
                      });
                    },
                  )),
            ));
  }

  void _insertSingleItem(String title) {
    int insertIndex = 0;
    tasksTodo.insert(
        insertIndex,
        ToDo(
            title: "$title",
            description: "",
            id: DateTime.now().millisecondsSinceEpoch,
            complete: false.toString()));
    _listKey.currentState.insertItem(insertIndex);
    tasksTodo.sort((a, b) => b.id.compareTo(a.id));
    database.deleteAll();
    for (ToDo data in tasksTodo) {
      database.addTodo(data);
    }
  }

  void _removeSingleItems(int index) {
    int removeIndex = index;
    AnimatedListRemovedItemBuilder builder = (context, animation) {
      return item(animation, removeIndex);
    };
    _listKey.currentState.removeItem(removeIndex, builder);
    tasksTodo.removeAt(removeIndex);
  }

  void fetchTodos() async {
    var allTasks = await database.fetchAll();
    setState(() {
      tasksTodo = allTasks;
    });
  }

  @override
  void initState() {
    database.initialize();
    fetchTodos();
    super.initState();
  }

  @override
  void dispose() {
    database.dispose();
    super.dispose();
  }

  Widget item(Animation animation, int index) {
    return FadeTransition(
      child: ListTile(
          title: Text("${tasksTodo[index].title}"),
          onTap: () {},
          leading: IconButton(
              icon: Icon(Icons.delete),
              onPressed: () {
                _removeSingleItems(index);
              }),
          trailing: Checkbox(
              value: tasksTodo[index].complete == true.toString(),
              onChanged: (bool value) {
                setState(() {
                  tasksTodo[index].complete = value.toString();
                });
                if (tasksTodo[index].complete == true.toString()) {
                  print('lol');
                }
              })),
      opacity: animation,
    );
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text("Tasks"),
      ),
      body: FutureBuilder(
          future: database.fetchAll(),
          builder: (context, snapshot) {
            return AnimatedSwitcher(
              duration: Duration(milliseconds: 250),
              child: snapshot.hasData
                  ? AnimatedList(
                      key: _listKey,
                      initialItemCount: tasksTodo.length,
                      itemBuilder: (context, index, animation) {
                        return item(animation, index);
                      })
                  : Center(child: CircularProgressIndicator()),
            );
          }),
      floatingActionButton: FloatingActionButton(
          child: Icon(Icons.add), onPressed: showTextfield),
    );
  }
}

// ToDo Class

class ToDo {
  int id;
  String title;
  String description;
  String complete;

  ToDo({this.title, this.description, this.id, this.complete});

  Map<String, dynamic> toMapp() {
    return {
      'title': title,
      'description': description,
      'id': id,
      'complete': complete
    };
  }

  ToDo.fromMapp(Map<String, dynamic> map)
      : title = map['title'],
        description = map['description'],
        id = map['id'],
        complete = map['complete'];
}