Flutter - How to create a CupertinoAlertDialog

You create a method and you show the dialog from there

import 'package:flutter/cupertino.dart';import 'package:flutter/material.dart';void main() => runApp(new MyApp());class MyApp extends StatelessWidget {  @override  Widget build(BuildContext context) {    return new MaterialApp(      title: 'Flutter Demo',      home: new MyHomePage(),    );  }}class MyHomePage extends StatefulWidget {  @override  _MyHomePageState createState() => new _MyHomePageState();}class _MyHomePageState extends State<MyHomePage> {  void displayDialog() {    showDialog(      context: context,      builder: (BuildContext context) => new CupertinoAlertDialog(            title: new Text("Alert"),            content: new Text("My alert message"),            actions: [              CupertinoDialogAction(                  isDefaultAction: true, child: new Text("Close"))            ],          ),    );  }  @override  Widget build(BuildContext context) {    return new Scaffold(      body: new Center(child: new Text("Welcome")),      floatingActionButton: new FloatingActionButton(        onPressed: displayDialog,        child: new Icon(Icons.add),      ),    );  }}

I had used localization in my project and that was main reason for this alertDialogLabel issue.

here is solution worked for me 'alertDialogLabel' was called on null