Raible Designs

Ajax and Open Laszlo with Max Carlson

Max is the co-founder and Lean Runtime Architect for Laszlo Systems. Max doesn't look at all like I pictured him (do they ever?!). He looks like a heavy-duty engineer, long curly hair, a little rough around the edges. I respect him more already. ;-)

Laszlo Systems Background: company founded in 2000. Laszlo Presentation Server (LPS) released in 2002. Embraced open source; LPS became OpenLaszlo. 2005: it's been widely adopted (130,000 downloads to date). This year, they're extending OpenLaszlo to support multiple runtimes, including DHTML. The company makes money of training and support, as well as developing custom applications (i.e. Laszlo Mail) and modules.

On 2/1/2006, Laszlo Systems joined a select group of tech leaders in establishing the Open Ajax community. Jointly committed to "making it easier for an open source community to form and popularize Ajax."

Demo's: Laszlo Mail, Pandora, Barclay's and Gliffy.

Developing with OpenLaszlo: XML-based, use your favorite XML editor. It's source-control friendly and has a library mechanism (for modularization). It's a familiar methodology for software engineers. It has standard OOP features: attributes and methods, class definitions with inheritance, familiar design patterns apply. There's an emphasis on declarative constructs. Finally, there's an open source Eclipse-based IDE4Laszlo. Originally developed by IBM, among the most popular downloads on alphaWorks. It now contains a WYSIWYG tool and is hosted at http://eclipse.org/laszlo.

LZX: Laszlo's XML Application Description Language: Flash independent tags and APIs (no ActionScript, movieClips, etc.; no need for Flash development). This allowed them to easily port to a different runtime. With OpenLaszlo, you can interface with your server via XML over HTTP, SOAP, XML-RPC and Java RPC. It has a runtime constraint system, hierarchical data binding with XPath. It has media, streaming support (although the Flash runtime seems to load images real slow - see the DHTML vs. Flash demo on http://openlaszlo.org).

Now Max is going through the Laszlo in Ten Minutes tutorial. If you haven't seen this, you should definitely check it out. It's a good quick introduction to OpenLaszlo. One of the unique features of OpenLaszlo is its components are written in LXZ. Compare this to XUL (components written in C) and Flex (components written in Flash) and it seems a lot more open.

In order to solve the nested-for-loops problem with JavaScript and DOM-manipulation, OpenLaszlo uses XPath and turns for loops into simple URL-like expressions. For example:

<text datapath="dset:/employee/firstName/text()"/>

Noticed on Max's Firefox toolbar: a del.iciou.us menu.

For the last 1/2 hour, Max has been talking about LZX, how to handle events, etc. In other words, since I've already worked with OpenLaszlo a bit, I haven't learned anything new.

Now Max is talking about OOP and how you can declare classes with certain attributes and then re-use them. It's kinda like Spring's "abstract beans" where you can declare a template bean and override attributes in child beans. In addition to allowing classes to be declared with no parent, you can create classes that extend an existing class. A common usage is declaring default values and then overriding visual elements (i.e. border size, colors, etc.).

OpenLaszlo 4.0 (with Ajax support) is targeted for a release by the end of the year.

Personally, I think OpenLaszlo is a very cool technology. However, it definitely needs a better IDE IMO. The last time I tried IDE4Laszlo on my Mac, it wasn't even close to useable. From a development perspective, using OpenLaszlo was difficult to work with because I felt like such a moron. With HTML and CSS, I know how to program UIs and it's difficult to give up that knowledge and rely on something else to provide the look and feel of my UI. In reality, I'm simply frustrated with my OpenLaszlo skills and would likely feel different if I was paid to develop a real-world application with it. After all, getting paid to work with a particular technology is almost always the best way to learn it.

Max is a great speaker and did a good job of introducing OpenLaszlo. Furthermore, this was one of the most interactive sessions I've seen at this conference. There's definitely a lot of folks interested in this technology.