Introduction
Just the other day, I blogged about “Enabling Frame Rate Counter for XAML Applications in Windows 8”. At the very end of that post, I reminded everyone that method does not work for HTML / JS Metro Applications. But, we are in luck as Mathias Jourdain provided sample code for accomplishing this in HTML / JS in his Build talk. The only problem was that he didn’t describe how to hook this into a new application to actually use. That is going to be the focus of today’s blog post.
Let’s get started.
Unlike XAML applications, this must be done using code. So, click on “Visual Studio 11” to begin.
Go ahead and click on “New Project…”
Select JavaScript –> Windows Metro Style –> Blank Application. Finally, give it a name and hit OK.
Our default.html will be displayed. We are going to keep things simple and only add a <p>
tag between the body and give it an id. Below is some sample code:
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title>FRCounter</title>
<link rel="stylesheet" href="http://www.codeproject.com/winjs/css/ui-dark.css" />
<script src="http://www.codeproject.com/winjs/js/base.js"></script>
<script src="http://www.codeproject.com/winjs/js/wwaapp.js"></script>
<link rel="stylesheet" href="http://www.codeproject.com/css/default.css" />
<script src="http://www.codeproject.com/js/default.js"></script>
</head>
<body>
<p id="myText" />
</body>
</html>
This paragraph tag will display our framerate when the application is running.
Now, if you switch over to the /js/default.js, then you will see the following code:
(function () {
'use strict';
WinJS.Application.onmainwindowactivated = function (e) {
if (e.detail.kind === Windows.ApplicationModel.Activation.ActivationKind.launch) {
}
}
WinJS.Application.start();
})();
You are going to replace it with this code:
var lastUIRefreshFPS = 0;
var frameCounter = 0;
(function () {
'use strict';
WinJS.Application.onmainwindowactivated = function(e) {
if (e.detail.kind === Windows.ApplicationModel.Activation.ActivationKind.launch) {
renderLoopFPS();
}
}
WinJS.Application.start();
})();
(function renderLoopFPS() {
var now = new Date().getTime() % 1000;
if (now < lastUIRefreshFPS) {
myText.innerText = frameCounter + " frames";
frameCounter = 0;
}
frameCounter += 1;
lastUIRefreshFPS = now;
msRequestAnimationFrame(renderLoopFPS);
})();
I made some very minor changes to this code and hooked it up to the onmainwindowactivated
event. This uses the msRequestAnimationFrame
method. You can read its documentation here.
If you run the app, you should get the following framerate in the middle of the screen as shown below:
It is quite a ways off compared to the detail of the XAML version of the framerate counter and was also more difficult to do (screenshots of XAML version below).
Now it is time for you to make the decision, do you develop in XAML / C# or HTML / JS? In this blog, we will be diving into XAML / C# with Metro, but may post the occasional HTML / JS app.
Thanks for reading!