roslib_dart/example/publisher/lib/main.dart
2022-02-22 20:23:58 +08:00

91 lines
2.1 KiB
Dart

import 'dart:async';
import 'package:flutter/material.dart';
import 'package:roslibdart/roslibdart.dart';
void main() {
runApp(const MyApp());
}
class MyApp extends StatelessWidget {
const MyApp({Key? key}) : super(key: key);
// This widget is the root of your application.
@override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Roslibdart Publisher Example',
theme: ThemeData(
primarySwatch: Colors.blue,
),
home: const MyHomePage(title: 'Roslibdart Publisher Example'),
);
}
}
class MyHomePage extends StatefulWidget {
const MyHomePage({Key? key, required this.title}) : super(key: key);
final String title;
@override
State<MyHomePage> createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
late Ros ros;
late Topic chatter;
@override
void initState() {
ros = Ros(url: 'ws://127.0.0.1:9090');
chatter = Topic(
ros: ros,
name: '/topic',
type: "std_msgs/String",
reconnectOnClose: true,
queueLength: 10,
queueSize: 10);
super.initState();
ros.connect();
Timer.periodic(const Duration(seconds: 3), (timer) async {
msgToPublished++;
Map<String, dynamic> json = {"data": msgToPublished.toString()};
await chatter.publish(json);
setState(() {});
});
}
int msgToPublished = 0;
void initConnection() async {
setState(() {});
}
void destroyConnection() async {
await ros.close();
setState(() {});
}
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
// Here we take the value from the MyHomePage object that was created by
// the App.build method, and use it to set our appbar title.
title: Text(widget.title),
),
body: Center(
// Center is a layout widget. It takes a single child and positions it
// in the middle of the parent.
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Text(msgToPublished.toString() + ' published'),
],
),
),
);
}
}