Using the new Page visibility API in your apps

One of the features lacking in the current browser api is that of determining whether the web page is currently visible to the user or is hidden (either in another tab or window).

The new Page Visibility API allows you to do just that – determine whether your web page is visible to the user, is hidden in a background tab or window, or is prerendering. It allows the developer to use the page visibility state in JavaScript logic to make the user experience more friendly; for example, by stopping video, animation or slideshow playback whenever the user switches to another browser tab or window, and resuming whenever the user switches back. Also if your page is doing some ajax processing periodically, which consumes precious system resources, we can pause it when the page is not in focus. Other use can be in analytics, checking how long the page had been in actual user focus, rather then as a hidden tab or window.

Check the below demo page to see how this works. The demo was tested in Safari, Opera 11.10, Chrome and Firefox.
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Adding HTML5 Geolocation to your web applications

One of the interesting and useful addition to the HTML5 specification is the Geolocation API. The Geolocation API allows users to share their location with web applications so that they can enjoy the benefits of various location-aware services.

Geolocation enables you as a developer or website owner to figure out where a particular user is located on the planet. This can be helpful in various web applications; for example in social networking, where you can find out where your various friends are currently located or in advertising where you can display targeted ads based on the users location.
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Drawing Trees in Canvas

Lately I’ve been experimenting with the new HTML5 Canvas element, and the best way to learn some new technology is to create something in it. For some time I’ve been dabbling in Processing and thought of porting some algorithms there in Canvas.
Rather than jumping into animation it was better to play around with static structures. I’ve a soft spot for visualizations so I decided to port some algorithms for creating recursive tree structures.
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HTML 5 logo announced

html 5 logo Now that people have slowly started implementing HTML 5 features in their sites they would like the world to know the same. W3C have released a set of logos you can stick on your site and announce the world of your HTML 5 accomplishments. Besides the primary logo it also include logos for other main features of HTML 5 – CSS, semantics, offline storage etc.
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