import 'package:flutter/material.dart';

void main() {
  runApp(
    MaterialApp(
      home: MyWidget(),
    ),
  );
}

class MyWidget extends StatelessWidget {
  TableRow header = const TableRow(
    children: [
      Padding(
        padding: EdgeInsets.symmetric(horizontal: 16, vertical: 12),
        child: Text(
          'Header1',
          style: TextStyle(fontWeight: FontWeight.bold),
        ),
      ),
      Padding(
        padding: EdgeInsets.symmetric(horizontal: 16, vertical: 12),
        child: Text(
          'Header2',
          style: TextStyle(fontWeight: FontWeight.bold),
        ),
      ),
      Padding(
        padding: EdgeInsets.symmetric(horizontal: 16, vertical: 12),
        child: Text(
          'Header3',
          style: TextStyle(fontWeight: FontWeight.bold),
        ),
      )
    ],
  );
  TableRow data = const TableRow(
    children: [
      Padding(
        padding: EdgeInsets.symmetric(horizontal: 16, vertical: 12),
        child: Text(
          'Data1',
        ),
      ),
      Padding(
        padding: EdgeInsets.symmetric(horizontal: 16, vertical: 12),
        child: Text(
          'Data2',
        ),
      ),
      Padding(
        padding: EdgeInsets.symmetric(horizontal: 16, vertical: 12),
        child: Text(
          'Data3',
        ),
      )
    ],
  );
  
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body:  Center(
        child: Table(
          border: TableBorder.all(),
          defaultColumnWidth: FixedColumnWidth(100),
          children: [
            header,
            data,
            data,
            data,
          ],
        ),
      ),
    );
  }
}