问颤动，在警报对话框中打开卡片内显示的文本

EN

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: HomePage(),
    );
  }
}

class HomePage extends StatefulWidget {
  @override
  _HomePageState createState() => _HomePageState();
}

class _HomePageState extends State<HomePage> {
  String displayText = "Same Text Everywhere";

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Center(
        child: GestureDetector(
          onTap: ()=> showMyDialog(context,displayText),
          child: Card(
            child: Padding(
              padding: const EdgeInsets.all(10.0),
              child: Text(displayText),
            ),
          ),
        )
      ),
    );
  }

  Future<void> showMyDialog(BuildContext context, String displayText) {
    return showDialog<void>(
      context: context,
      builder: (BuildContext context) {
        return AlertDialog(
          content: Text(displayText),
        );
      },
    );
  }


}