Flutter Flatter Web收听通过iFrame发布的事件
我的目标是在主页上的iframe帮助下集成一个flatter小部件。主页不是用flatter编写的。但是,我需要一个界面,主页可以通过该界面与小部件进行通信。因此,我想到在主页上使用postMessage(),在flatter小部件中使用html.window.addEventListener()。现在我收到了一个事件,但无法看到它的内容。我的临时解决方案是将消息保存在本地存储中,并且只将侦听器用作通知程序,但我并不喜欢这种方法。有谁能更好地解决我的问题吗 颤振测试小部件:Flutter Flatter Web收听通过iFrame发布的事件,flutter,iframe,local-storage,flutter-web,postmessage,Flutter,Iframe,Local Storage,Flutter Web,Postmessage,我的目标是在主页上的iframe帮助下集成一个flatter小部件。主页不是用flatter编写的。但是,我需要一个界面,主页可以通过该界面与小部件进行通信。因此,我想到在主页上使用postMessage(),在flatter小部件中使用html.window.addEventListener()。现在我收到了一个事件,但无法看到它的内容。我的临时解决方案是将消息保存在本地存储中,并且只将侦听器用作通知程序,但我并不喜欢这种方法。有谁能更好地解决我的问题吗 颤振测试小部件: // ignore
// ignore: avoid_web_libraries_in_flutter
import 'dart:html' as html;
import 'package:simple_cookies/simple_cookies.dart';
class MessageListener extends StatefulWidget {
@override
_MessageListenerState createState() => _MessageListenerState();
}
class _MessageListenerState extends State<MessageListener> {
String last;
@override
void initState() {
html.window.addEventListener('message', listen, true);
super.initState();
}
@override
void dispose() {
html.window.removeEventListener('message', listen, true);
super.dispose();
}
void listen(html.Event event) {
last = Cookies.get('iframe_message') ?? 'Error';
setState(() {});
}
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('iFrame Test'),
),
body: Center(
child: SingleChildScrollView(child: Text(last ?? 'No messages yet')),
),
);
}
}
<html>
<head>
<title>website title</title>
<script type="text/javascript">
function pageProcessing() {
let messageButton = window.document.getElementById("post_message");
messageButton.addEventListener("click", () => {
let message = window.document.getElementById("message_text").value;
window.localStorage.setItem("iframe_message", message);
document.getElementById('flutter_widget').contentWindow.postMessage(
{
sender: "main_page",
message: message
},
"*"
);
});
}
window.document.addEventListener('readystatechange', () => {
if (window.document.readyState == 'complete') {
pageProcessing();
}
}
);
</script>
</head>
<body>
<div>
<input type="text" id="message_text"> <input type="button" id="post_message" value="Send Message">
</div>
<iframe id="flutter_widget" src="http://testing.orcaf#####"></iframe>
</body>
</html>
//忽略:避免web库在flatter中
将“dart:html”导入为html;
导入“package:simple_cookies/simple_cookies.dart”;
类MessageListener扩展了StatefulWidget{
@凌驾
_MessageListenerState createState()=>\u MessageListenerState();
}
类_MessageListenerState扩展状态{
最后一串;
@凌驾
void initState(){
html.window.addEventListener('message',listen,true);
super.initState();
}
@凌驾
无效处置(){
removeEventListener('message',listen,true);
super.dispose();
}
void侦听(html.Event){
last=Cookies.get('iframe_message')??“Error”;
setState((){});
}
@凌驾
小部件构建(构建上下文){
返回脚手架(
appBar:appBar(
标题:文本(“iFrame测试”),
),
正文:中(
子项:SingleChildScrollView(子项:文本(最后一个??“还没有消息”),
),
);
}
}
主页:
// ignore: avoid_web_libraries_in_flutter
import 'dart:html' as html;
import 'package:simple_cookies/simple_cookies.dart';
class MessageListener extends StatefulWidget {
@override
_MessageListenerState createState() => _MessageListenerState();
}
class _MessageListenerState extends State<MessageListener> {
String last;
@override
void initState() {
html.window.addEventListener('message', listen, true);
super.initState();
}
@override
void dispose() {
html.window.removeEventListener('message', listen, true);
super.dispose();
}
void listen(html.Event event) {
last = Cookies.get('iframe_message') ?? 'Error';
setState(() {});
}
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('iFrame Test'),
),
body: Center(
child: SingleChildScrollView(child: Text(last ?? 'No messages yet')),
),
);
}
}
<html>
<head>
<title>website title</title>
<script type="text/javascript">
function pageProcessing() {
let messageButton = window.document.getElementById("post_message");
messageButton.addEventListener("click", () => {
let message = window.document.getElementById("message_text").value;
window.localStorage.setItem("iframe_message", message);
document.getElementById('flutter_widget').contentWindow.postMessage(
{
sender: "main_page",
message: message
},
"*"
);
});
}
window.document.addEventListener('readystatechange', () => {
if (window.document.readyState == 'complete') {
pageProcessing();
}
}
);
</script>
</head>
<body>
<div>
<input type="text" id="message_text"> <input type="button" id="post_message" value="Send Message">
</div>
<iframe id="flutter_widget" src="http://testing.orcaf#####"></iframe>
</body>
</html>
网站标题
函数pageProcessing(){
让messageButton=window.document.getElementById(“post_消息”);
messageButton.addEventListener(“单击”,()=>{
让message=window.document.getElementById(“message_text”).value;
setItem(“iframe_message”,message);
document.getElementById('flatter_widget').contentWindow.postMessage(
{
发件人:“主页”,
信息:信息
},
"*"
);
});
}
window.document.addEventListener('readystatechange',()=>{
如果(window.document.readyState=='complete'){
页面处理();
}
}
);
要从侦听器读取消息数据,您必须将事件强制转换为MessageEvent
:
void侦听(html.Event){
var data=(事件为html.MessageEvent).data;
打印(数据['sender']);
打印(数据['message']);
设置状态(){
//...
});
}