Flutterでアプリ開発するうえでの基礎

name: {アプリ名}
flutter:
  uses-material-design: true

import 'package:flutter/material.dart';

class MyButton extends StatelessWidget {
  const MyButton({super.key});

  @override
  Widget build(BuildContext context) {
    return GestureDetector(
      onTap: () {
        print('MyButton was tapped!');
      },
      child: Container(
        height: 50.0,
        padding: const EdgeInsets.all(8.0),
        margin: const EdgeInsets.symmetric(horizontal: 8.0),
        decoration: BoxDecoration(
          borderRadius: BorderRadius.circular(5.0),
          color: Colors.lightGreen[500],
        ),
        child: const Center(
          child: Text('Engage'),
        ),
      ),
    );
  }
}

void main() {
  runApp(
    const MaterialApp(
      home: Scaffold(
        body: Center(
          child: MyButton(),
        ),
      ),
    ),
  );
}

class WinTypeScreen extends StatefulWidget {
  @override
  WinTypeContainer createState() => WinTypeContainer();
}

enum WinType {
  tsumo,
  ron
}

class WinTypeContainer extends State<WinTypeScreen> {

  WinType _winType = WinType.tsumo;

  @override
  Widget build(BuildContext context) {
    return Scaffold(
        body: SafeArea(
          child:Column(
            children: [
              SizedBox(width: 200, height: 50.0),
              RadioListTile(
                title:Text("ツモ"),
                value: WinType.tsumo,
                groupValue: _winType,
                onChanged:(value) => _selectedWinType(value),
              ),
              RadioListTile(
                title:Text("ロン"),
                value: WinType.ron,
                groupValue: _winType,
                onChanged:(value) => _selectedWinType(value),
              )
            ],
          )
        )
    );
  }
  _selectedWinType(value) {
    setState(() {
      _winType = value;
    });
  }
}

import 'package:flutter/cupertino.dart';

enum FourWindOrderType {
  east,
  south,
  weat,
  north
}

class FourWindOrderScreen extends StatefulWidget {
  @override
  FourWindOrderContainer createState() => FourWindOrderContainer();
}

class FourWindOrderContainer extends State<FourWindOrderScreen> {

  FourWindOrderType _windType = FourWindOrderType.east;

  final Map<FourWindOrderType, Widget> windSegment = const <FourWindOrderType, Widget>{
    FourWindOrderType.east: Text("東家"),
    FourWindOrderType.south: Text("南家"),
    FourWindOrderType.weat: Text("西家"),
    FourWindOrderType.north: Text("北家"),
  };

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: CupertinoSlidingSegmentedControl(
          children: windSegment,
          thumbColor: CupertinoColors.activeBlue,
          groupValue: _windType,
          onValueChanged: (newValue) {
            setState(() {
              _windType = newValue as FourWindOrderType;
              print(_windType);
            });
          }),
    );
  }
}

class ReachScreen extends StatefulWidget {
  @override
  ReachContainer createState() => ReachContainer();
}

class ReachContainer extends State<ReachScreen> {

  bool isReach = false;

  @override
  Widget build(BuildContext context) {
    Switch reachSwitch = Switch(value: this.isReach,
        activeColor: Colors.purple,
        activeTrackColor: Colors.black,
        inactiveThumbColor: Colors.yellow,
        inactiveTrackColor: Colors.green,
        onChanged: _changeReachSwitch);

    return Scaffold(
      body: Row(children: [
        Text("立直"),
        reachSwitch,
      ],)
    );
  }

  _changeReachSwitch(bool isReach) {
    setState(() {
      this.isReach = isReach;
      print("立直：${this.isReach}");
    });
  }
}

class ConsecutiveWinsScreen extends StatefulWidget {
  @override
  ConsecutiveWinsContainer createState() => ConsecutiveWinsContainer();
}

class ConsecutiveWinsContainer extends State<ConsecutiveWinsScreen> {
  List<DropdownMenuItem> _items = [];
  int _consecutiveWins = 0;

  @override
  void initState() {
    super.initState();
    setItems();
    _consecutiveWins = _items[0].value;
  }

  void setItems() {
    for(var i = 0; i < 9;i++) {
      _items.add(DropdownMenuItem(
        child: Text("${i}本場"),
        value: i,
      ));
    }
  }

  @override
  Widget build(BuildContext context) {

    DropdownButton consecutiveWinsDropButton = DropdownButton(
      value: _consecutiveWins,
      onChanged: (value) {
        setState(() {
          _consecutiveWins = value;
          print("${_consecutiveWins}本場");
        });
      },
      items: _items,
    );


    return Scaffold(
        body: Row(children: [
          Text("積み棒"),
          consecutiveWinsDropButton,
        ],)
    );
  }
}

class TileButtonCellScreen extends StatefulWidget {
  final String imagePath;
  final Function cellTapped;

  TileButtonCellScreen({required this.imagePath, required this.cellTapped});

  @override
  TileButtonCellContainer createState() => TileButtonCellContainer(imagePath: this.imagePath, cellTapped: this.cellTapped);
}

class TileButtonCellContainer extends State<TileButtonCellScreen> {
  int _tapCount = 4;
  final String imagePath;
  final Function cellTapped;  //****** デリゲートメソッドの受け取り先 ******//

  TileButtonCellContainer({required this.imagePath, required this.cellTapped});

  @override
  Widget build(BuildContext context) {
    return InkWell(
      onTap: (){
      setState(() {
      if (_tapCount > 0) {
        _tapCount--;
        print("count:${_tapCount}");
        this.cellTapped(); //****** デリゲートメソッド実行部分 ******//
      }});
      },
    child: /* 中略 */
    );
  }
}

class TileButtonScreen extends StatefulWidget {
  @override
  TileButtonContainer createState() => TileButtonContainer();
}

class TileButtonContainer extends State<TileButtonScreen> {
  
  //****** デリゲートメソッドの定義 ******//
  void _cellTapped() {
    print("TileButtonContainerの処理です");
  }

  TileButtonContainer() {
    _viewData.add(TileButtonCellScreen(imagePath: /** imagePath **/,
        cellTapped: _cellTapped)); //****** デリゲートメソッド代入 ******//
  }

  var _viewData = <Widget>[];

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: /** 中略 **/
          children: _viewData),
    );
  }
}

  @override
  Widget build(BuildContext context) {
    return InkWell(
      onTap: (){
      setState(() {
      if (_tapCount > 0) {
        _tapCount--;
        print("count:${_tapCount}");
        this.cellTapped();
      }});
      },
    child: Row(
          children: [
          Image(image: AssetImage(this.imagePath),
         fit: BoxFit.fitHeight, height: 700),
         Text("${_tapCount}")
        ],
        // mainAxisAlignment: MainAxisAlignment.center,
        ),
      );
  }

class TileButtonContainer extends State<TileButtonScreen> {
  List<List<Widget>> _allTiles = [];
  var _manTiles = <Widget>[];
  var _pinTiles = <Widget>[];
  var _souTiles = <Widget>[];
  var _charTiles = <Widget>[];

  List<String> sectionTitle = ["萬子", "筒子", "索子", "字牌"];

  TileButtonContainer() {
    /******** _manTiles要素追加 ********/
    /******** _pinTiles要素追加 ********/
    /******** _souTiles要素追加 ********/
    /******** _charTiles要素追加 ********/

    _allTiles = [_manTiles, _pinTiles, _souTiles, _charTiles];
  }

  @override
  Widget build(BuildContext context) {
    return new Scaffold(
      backgroundColor: Colors.orange,
      body: new Container(
        child: new ListView.builder(
                shrinkWrap: true,
                itemCount: _allTiles.length,
                itemBuilder: (context, index) {
                  return new Column(
                    children: <Widget>[
                      new Container(
                        color: Colors.green,
                        child: new Row(
                          mainAxisAlignment: MainAxisAlignment.center,
                          children: <Widget>[
                            new Text(sectionTitle[index],
                                style: new TextStyle(
                                    fontSize: 20.0, color: Colors.white)),
                          ],
                        ),
                      ),
                      new Container(
                        child: new GridView.count(
                          shrinkWrap: true,
                          crossAxisCount: 5,
                          physics: NeverScrollableScrollPhysics(),
                          children: _allTiles[index],
                        ),
                      ),
                    ],
                  );
                  },
        ),
      ),
    );
  }

  void _cellTapped() {
    print("TileButtonContainerの処理です");
  }
}

  @override
  Widget build(BuildContext context) {
    return Scaffold(
        body: TextField(enabled: true,
              maxLength: 2,
              style: TextStyle(color: Colors.black),
              maxLines: 1,
              onChanged: _handleText,
              decoration: InputDecoration(
                hintText: "立直棒の数"
              )
          )
    );
  }

flutter:
  uses-material-design: true
  assets:
  // ディレクトリ名は自由と思われる
    - assets/images/

// 画像呼び出し箇所
Image.asset("assets/images/man$1.jpeg", fit: BoxFit.fitHeight, height: 700),