VisualAspects

From APIDesign

Visual Aspects

The usual consensus is that visual aspects that are presented just to the end user are not part of API of some application. This is usually well justified and correct, especially in multi-platform framework like Java. Programmers that would rely on some library to render a button 8px next to right border, with a certain text painted in dedicated RGB color could be successful with their application on one screen resolution, while horribly fail on small monitors with limited gray scale. Common sense suggests that writing this kind of checks is against good habits of using APIs.

However recently I had an opportunity to face this kind of rendering bug. Stylesheets of this website were reported to be broken on firefox 3.0, while working fine on other browsers and older versions of firefox itself. The text in the navigation and toolbox areas were supposed to be black with yellow background, but for some reason firefox 3.0 was able to render it without the desired background. Some users reported that reading black text on black background is not really pleasant.

I was not sure where is the bug and I asked for help the mozilla guys. To my surprise they reacted pretty quickly, verified that this is behaviour of Opera and other browsers as well and even suggested how to fix my CSS files. Thanks guys, my website is looking much better now. However this leads me to two API observations:

• If I used an API in some version and it used to work, I consider it a bug that it does not work in new releases. I guess many programmers feel the same. And this all applies in some situations even to visual outcomes.
• Even rendering can sometimes become part of API, especially if you accidentally start to render black text on black background, there will be many people who complain about behaviour of your rendering engine.

Still, I'd like to apologize and thank mozilla guys for quick resolution and help. Solving incompatibilities between versions of some product is definitely much easier with such great support that I got as part of 449911 issue. Thanks.

--JaroslavTulach 13:55, 11 August 2008 (UTC)

<comments/>