January 2007 Entries

Problems caused by concurrent asynchronous calls to web services

What's COMET? When an Internet Application needs to be updated regularly, the only possible choice is to use polling. The HTTP protocol makes it impossible to have the server "push" data to the client. The faster the client needs to be updated, the faster the poll must be. Of course, there are limits, for example due to the network speed, the load, etc. A possible alternative is known under the name COMET. (Note: COMET is usually used as an alternative to AJAX, and AJAX implies the use of JavaScript ......

JavaScript: CSS length manipulation and conversion

CssLength class: In the course of improving my DHTML PositionedNode, one thing I really wanted is to be able to handle other units than just pixels. In order to do that, some conversions are needed. To make this easier, I developed a helper class named CssLength. Converting from one unit to the other can be tricky. The conversion depends on quite a few things (mostly the way font size is set in the node's hierarchy in the DOM), and there is not a simple arithmetic way to convert ems to pixels for ......

L'Abbé Pierre is dead...

I was about to write an article about object oriented inheritance in JavaScript yesterday when I heard of the death of the Abbé Pierre. After that, it was kind of hard to talk about prototypes and base classes. The Abbé Pierre had very strong ties with Switzerland, and indirect ties with another figure I admire a lot and was lucky enough to meet a few times, Dr Jack Preger. In 2004, Dr Preger was invited in Saillon to take care of the symbolic 'Vigne à Farinet', of which the Abbé Pierre was the honorary ......

WPF scalability wishes / MIX07

I received today the confirmation to my registration for MIX07 in Las Vegas. I am very excited to go and attend this event again. Last year's MIX06 has been a defining event for me, followed by intensive work to introduce WPF into my firm. So far this activity was a success, and I am very excited to see the "real" development activities starting (as oppposed to prototyping, which we did most of last year). This year's MIX07's major technology is probably going to be WPF/E. While we don't plan to ......

DHTML effect: Positioning

Continuing to clean up the DHTML effects I use on my site (see my previous post), I published a Positioning and Scrolling effect. It's quite handy, in that it allows to easily keep a DOM node (DIV, ...) in sight of the user at all times. This can be used, for example, for a "floating menu" like I have on my main page. The DOM node moves with a variable speed. What I especially like in the way this effect is implemented is that the user can specify his own function to calculate the speed of the DOM ......

DHTML effect: Fading

I am working on a new addition to my RealSimpleBlog control (more about that later), and that gives me the occasion to clean up a few DHTML effects I have on my website. The goal is to make a JavaScript library, which, contrarily to the well known prototype.js or others, should be lean and modular, and use advanced JavaScript programming technique while sticking to accepted best practices for JavaScript programming (quite a program... To achieve this, I have one JavaScript file per effect (this allows ......

Christmas in the family / German road trip

Christmas in Lausanne We celebrated Christmas in the family in western Switzerland as usual, this year at my parents' place in Lausanne. it was a very nice and cosy time, a good occasion to see all the family members in a relaxed atmosphere. The girls were a little overwhelmed by all the emotions (and the presents :-) but everything went great. more... and more... Burg Hohenzollern On the 27th, we packed our things and drove north to Schaffhausen first, and then over the german border to Burg Hohenzollern ......

Happy new MVP year!

First of all, Happy new year. I am not really into the whole new year celebration, and I most certainly don't think that just because a digit gets changed in an arbitrary number, suddenly there will be no more wars, no more tragical events, no more hunger... So it's a bit hard for me to get in the celebration craze, and we spent a quiet evening. Nonetheless, happy new year to all readers and may next year bring you and your families what you all wish :-) Today, to start the year, I had a nice surprise ......