QWebView XMLHttpRequest performance

**theH** · 22nd September 2012, 12:25

Hello,

I have created a simple Qt application with a webview and let it load a url:

Qt Code:

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webView = new QWebView(this);
setCentralWidget(webView);
webView->load(QUrl("http://localhost:8080/responsetest.html"));

webView = new QWebView(this);
setCentralWidget(webView);
webView->load(QUrl("http://localhost:8080/responsetest.html"));

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This loads a html page which uses XMLHttpRequest and displays the time it took to load it:

Qt Code:

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<html>
    <body>
		<script>
			var num = 0;
 
			function mouseClicked()
			{
				num++;
				var time = new Date().getTime();
 
				var xmlhttp = new XMLHttpRequest();
 
				xmlhttp.onreadystatechange = function()
				{
					if (xmlhttp.readyState==4 && xmlhttp.status==200)
					{
						time =  new Date().getTime() - time;
						document.getElementById('link').innerHTML = "Response "+num+" took "+time+"ms.";
					}
				}
				xmlhttp.open("GET", "responsetest.html?q="+time, true);
				xmlhttp.send();
			}
		</script>
		<div><a onclick="mouseClicked()" id="link" href="#" >click me</a></div>
    </body>
</html>

<html>
    <body>
		<script>
			var num = 0;
			
			function mouseClicked()
			{
				num++;
				var time = new Date().getTime();
				
				var xmlhttp = new XMLHttpRequest();
				
				xmlhttp.onreadystatechange = function()
				{
					if (xmlhttp.readyState==4 && xmlhttp.status==200)
					{
						time =  new Date().getTime() - time;
						document.getElementById('link').innerHTML = "Response "+num+" took "+time+"ms.";
					}
				}
				xmlhttp.open("GET", "responsetest.html?q="+time, true);
				xmlhttp.send();
			}
		</script>
		<div><a onclick="mouseClicked()" id="link" href="#" >click me</a></div>
    </body>
</html>

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The thing is, it takes more than a second to load whereas other browsers need 7 milliseconds!

Actually, my local server (mongoose) shows, that Qt is waiting one second before it is even attempting the request. Is that at all possible? And how could I fix it?

I found out that even Safari shows this behaviour but Chrome and Firefox don't. What could be behind this?

Cheers!