tetujin

import 'package:flutter/material.dart';

import 'package:location/location.dart';
import 'package:flutter_map/flutter_map.dart';
import 'package:latlong2/latlong.dart';

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void main() => runApp(MyApp());

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tetujin

import 'dart:convert';
import 'package:flutter/material.dart';
import 'package:shared_preferences/shared_preferences.dart';

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void main() => runApp(MyApp());

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class MyApp extends StatelessWidget {
  @override

tetujin

import 'dart:convert';

void main() {
  var mapObj = {"title":"TODO-1", "status":true};
  print(mapObj);
  
  var jsonStr = jsonEncode(mapObj);
  print(jsonStr);
  
  var mapObj2 = jsonDecode(jsonStr);

tetujin

import 'package:flutter/material.dart';

import 'package:http/http.dart' as http;
import 'dart:convert' as convert;

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {

tetujin

// ① APIの利用に必要なライブラリをインポートする
import 'package:http/http.dart' as http;
import 'dart:convert' as convert;

void main() async {
  // ② APIにアクセスする
  var url = Uri.parse(
      'https://mocha-api.t.u-tokyo.ac.jp/resource/channel/utokyo_all/congestion');
  var response = await http.get(url);

tetujin

import 'package:flutter/material.dart';
import 'package:sensors/sensors.dart';

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void main() => runApp(MyApp());

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class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {

tetujin

import 'package:flutter/material.dart';

///////////////////////////////
void main() => runApp(MyApp());

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class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(theme: ThemeData(), home: MyHomePage());

tetujin

  final _textFieldController = TextEditingController();

  Future<String?> _showTextInputDialog(BuildContext context) async {
    return showDialog(
        context: context,
        builder: (context) {
          return AlertDialog(
            title: const Text('タイトル'),
            content: TextField(
              controller: _textFieldController,

tetujin

import 'package:flutter/material.dart';

// ①　必要なライブラリをインポート
import 'package:shared_preferences/shared_preferences.dart';

///////////////////////////////
void main() => runApp(MyApp());

///////////////////////////////
class MyApp extends StatelessWidget {

tetujin

import 'package:flutter/material.dart';

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// ① Main：Flutterアプリもmain()からコードが実行されます。
// `void main() => runApp(MyApp());` でも意味は同じです。
void main() {
  return runApp(MyApp());
}

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