From Forum Nokia Wiki

Review:

This article covers an interesting topic that is particularly relevant, given the recent rapid rise in the number of touch-screen devices Nokia is bringing to market. The article shows how tap detection options can be used to alter the way a midlet which makes use of a Canvas interprets tap events on touch-screen devices. Often when the user taps on the screen, there is a small difference between where they put the stylus (or their finger) on the screen and the co-ordinates where they lift it up. This may be entirely unintentional, but may be interpreted by the midlet as a drag event instead of a tap event. Also, it may lead to selection errors. Furthermore, unnecessarily many drag events can also be generated. This article shows how through the use of a simple property in the JAD file, we can address these problems. Basically, by setting the Nokia-MIDlet-Tap-Detection-Options in the JAD file, drag events which occur over a short time within a small area are suppressed and the pointer down and pointer up co-ordinates are set to be the same.

I wasn't aware of this feature (and the associated JAD property) until reading this article, so it made for very interesting reading. This is certainly likely to be of interest to those developing for touch-screen Nokia devices, as selection errors are pretty common on touch-screen devices for the reasons identified in this article. The concepts are nicely illustrated using graphical examples, and examples of setting the JAD option are also usefully provided (along with a discussion of how the different settings will affect midlet behavior).

--Larry101 17:45, 29 September 2009 (UTC)