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Using HTML5's FullScreen API


I've been looking into ways in which a web application can be made more user friendly and HTML5 does include some powerful features such as PageVisibility, Navigation Timing, etc,. that can be used to provide good user experience. Today I was looking into FullScreen API that allows you show any of the elements in the DOM in Full-Screen mode. Suppose you have a HTML5 video embedded in a page and would like to play that video in full-screen mode then it is now possible with the FullScreen API. Similarly say if you have an image element, it can also be shown in full screen mode.

To present a element in the full-screen mode you have to call the method requestFullScreen() on that element. I've created a demo that shows a picture and when you click on a button it shows it in the full-screen mode and then changes the picture every three seconds creating a slideshow like experience.

Here's the code:

<!DOCTYPE HTML> <html> <head> <script type="text/javascript"> //list of images for the slideshow var imageList = ["Image3.jpg", "Image4.jpg", "Image5.jpg"]; var count = 0; //invoke this when user wants to see a Full Screen Slideshow function enterFullScreen(){ var elem = document.getElementById("slideshow"); //show full screen elem.webkitRequestFullScreen(); setTimeout(changePicture, 3000); } function changePicture(){ count++; //cycle through the list of images document.getElementById("image1").src = imageList[count % imageList.length]; if (document.webkitIsFullScreen) setTimeout(changePicture, 3000); else //if user exits the full screen mode document.getElementById("image1").src = imageList[0]; } </script> </head> <body> <div id="slideshow"> <img id="image1" src="Image3.jpg"><img> </div> <br> <input type="button" value="Enter full screen mode" onclick=enterFullScreen()> </body> </html>

When you click the button - 'Enter full screen mode' it calls the user defined method - enterFullScreen. In this method a call is made to the method webkitRequestFullScreen on the element that we want to show in full-screen mode. I'm using Google chrome and hence the method requestFullScreen with a prefix 'webkit'. On firefox it would be 'moz'. A slideshow like effect is created by looping through the images in the function changePicture.

To exit from the full-screen mode you can press the 'Esc' key. In the changePicture method I'm checking whether the full-screen mode is still activated by referring to the variable webkitIsFullScreen defined in the document object. It returns true if full-screen mode is activated and false otherwise. 


Comments

  1. Hei thanks for the code. I searched many sites, at last I got your web link. check here for future use HTML5 Slider and HTML5 Slideshow

    ReplyDelete
  2. For requesting method in IE, I have used msRequestFullScreen.......But it is not working...What is the solution???

    ReplyDelete
  3. For IE i have used msRequestFullScreen....but it is not working...What is the solution???

    ReplyDelete
  4. FullScreen API is supported in Chrome, Safari and Firefox. Unfortunately it is not supported in IE.

    ReplyDelete

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