import 'package:flutter/material.dart';

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: MyHomePage(title: 'Flutter Demo Basic Properties'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  MyHomePage({Key key, this.title}) : super(key: key);

  final String title;

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

class _MyHomePageState extends State<MyHomePage> {
  bool _pushed = false;

  // 子ウィジェットの表示位置のリスト
  List<Map<int, TableColumnWidth>> _list = [
    // 各ウィジェットを1:2:3の比で表示する
    {0: FlexColumnWidth(1), 1: FlexColumnWidth(2), 2: FlexColumnWidth(3)},
    /* IntrinsicColumnWidthは子ウィジェットの横幅に合わせて表示
       引数なしのFlexColumnWidthは余った幅いっぱいに表示
       FixedColumnWidthは幅を固定表示
    */
    {0: IntrinsicColumnWidth(), 1: FlexColumnWidth(), 2: FixedColumnWidth(100)},
  ];

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text(widget.title)),
      floatingActionButton: FloatingActionButton(
        child: Text("B"),
        onPressed: () {
          setState(() {
            _pushed = !_pushed;
          });
        },
      ),
      body: Table(
        // ポーダーラインをつける
        border: TableBorder.all(color: Colors.blueAccent),
        // ウィジェットの表示を設定する
        columnWidths: _pushed ? _list[1] : _list[0],
        children: <TableRow>[
          TableRow(
            children: [
              myWidget(
                color: Colors.red,
                text: "red",
                height: 200.0,
              ),
              // セルごとに細かな設定も可能
              TableCell(
                verticalAlignment: TableCellVerticalAlignment.bottom,
                child: myWidget(
                  color: Colors.blue,
                  text: "blue",
                  height: 100.0,
                ),
              ),
              myWidget(
                color: Colors.green,
                text: "green",
                height: 100.0,
              ),
            ],
          ),
          TableRow(
            children: [
              myWidget(
                color: Colors.green,
                text: "green",
                height: 100.0,
              ),
              myWidget(
                color: Colors.red,
                text: "red",
                height: 100.0,
              ),
              myWidget(
                color: Colors.blue,
                text: "blue",
                height: 200.0,
              ),
            ],
          ),
        ],
      ),
    );
  }

  Widget myWidget({Color color, String text, double height}) {
    return Padding(
      padding: const EdgeInsets.all(8.0),
      child: Container(
        height: height,
        color: color,
        child: Text(text),
      ),
    );
  }
}