ex:

import 'package:flutter/material.dart';

void main() => runApp(MaterialApp(
  home: HomePage(),
));

class HomePage extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Center(
        child: MyButton(),
      ),
    );
  }
}

class MyButton extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return GestureDetector(
      onTap: () {//点击
        print('onTap');
      },
      onDoubleTap: (){//双击
        print('double type');
      },
      child: Container(
        decoration: BoxDecoration(
          borderRadius: BorderRadius.circular(5.0),
          color: Theme.of(context).buttonColor,
        ),
        padding: EdgeInsets.all(20.0),
        child: Text('MyButton'),
      ),
    );
  }
}

输出：