问如何使用flutter local_notification软件包显示平视通知？

EN

import 'dart:async';
import 'package:flutter/material.dart';
import 'package:flutter_local_notifications/flutter_local_notifications.dart';

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

class MyApp extends StatefulWidget {
  @override
  _MyAppState createState() => new _MyAppState();
}

class _MyAppState extends State<MyApp> {
  FlutterLocalNotificationsPlugin flutterLocalNotificationsPlugin;

  @override
  initState() {
    super.initState();
    var initializationSettingsAndroid =
    new AndroidInitializationSettings('@mipmap/ic_launcher');
    var initializationSettingsIOS = new IOSInitializationSettings();
    var initializationSettings = new InitializationSettings(android: initializationSettingsAndroid, iOS: initializationSettingsIOS);
    flutterLocalNotificationsPlugin = new FlutterLocalNotificationsPlugin();
    flutterLocalNotificationsPlugin.initialize(initializationSettings,
        onSelectNotification: onSelectNotification);
  }
  @override
  Widget build(BuildContext context) {
    return new MaterialApp(
      home: new Scaffold(
        appBar: new AppBar(
          title: new Text('Plugin example app'),
        ),
        body: new Center(
          child: new Column(
            mainAxisAlignment: MainAxisAlignment.center,
            mainAxisSize: MainAxisSize.max,
            children: <Widget>[
              new RaisedButton(
                onPressed: _showNotification,
                child: new Text('Show Notification'),
              ),
            ],
          ),
        ),
      ),
    );
  }
  Future _showNotification() async {
    const AndroidNotificationDetails androidPlatformChannelSpecifics =
    AndroidNotificationDetails(
        'your channel id', 'your channel name', 'your channel description',
        importance: Importance.max,
        priority: Priority.high,
        showWhen: true);
    const NotificationDetails platformChannelSpecifics =
    NotificationDetails(android: androidPlatformChannelSpecifics);
    await flutterLocalNotificationsPlugin.show(
        0, 'plain title', 'plain body', platformChannelSpecifics,
        payload: 'item x');
  }

  Future onSelectNotification(String payload) async {
    showDialog(
      context: context,
      builder: (_) {
        return new AlertDialog(
          title: Text("Your Notification Detail"),
          content: Text("Payload : $payload"),
        );
      },
    );
  }
}