Improving an Image Zooming Application with JavaScript
Among the plethora of JavaScript applications that can be developed to extend the existing functionality of a web site, zooming into and out of bitmapped images is quite possibly one of easiest to build and implement. Thus, if you’re a web developer who’s interested in learning how to incorporate basic zooming capabilities into your own web applications, then don’t waste any more time. Start reading this article now!
Improving an Image Zooming Application with JavaScript - Listing the improved source code (Page 4 of 4 )
In consonance with the concepts that I deployed in the prior section of this tutorial, the only thing that remains undone is joining all the modules of this JavaScript-driven zooming application. In this manner, you can understand how they link with each other.
That being clarified, have a look at the signature of the following (X)HTML file, which as I said before, comprises the complete source code corresponding to this image zooming application. Here's how this file is defined:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
There you have it. At this point, I've provided you with the full source code required to get this JavaScript-driven zooming application working seamlessly. It's highly recommended that you study in detail the previous script and eventually introduce all the changes that you consider necessary into it to suit your personal needs and extend your existing skills in developing useful web applications with JavaScript.
The experience will hopefully be educational!
Final thoughts
In this second part of the series, I demonstrated through a few simple code samples how to improve the original behavioral layer of the image zooming application. I merged its two primary JavaScript functions into only one, making it a bit more compact and efficient.
However, as you may have noticed, the application's overall functionality is pretty limited, since it's only capable of zooming into and out of one image. Therefore, in the next tutorial of the series, I'm going to address the limitation by providing the application with the ability to work with multiple images.
Now that you know what the next article will be about, you don't have any excuses to miss it!
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Working with Multiple Graphics for a Zoom Application in JavaScript
