use of SWF

[mwalker]

Hello, I am wondering if anyone can explain the use of shockwave files on the various demo apps, (specifically the weather app). I ask since I am somewhat intimidated by shockwave files - have never edited or created one and wondering how crucial it is to the overall functionality of the weather app.

Much thanks.

-Matt

[antun]

Actually you never work directly with SWF files, except if you're using a SWF as an art asset.

The way the Laszlo Presentation Server works is by compiling LZX code (similar to XML & JavaScript) into SWF bytecode and returning that to your browser. The Flash Player is what renders Laszlo applications.

If you want to quickly experience what it's like to develop a Laszlo application, you can use the LZXplorer:

http://www.laszlosystems.com/lps/lzxplorer2/lzxplorer.htm

This is what the LZX source for the weather app looks like:

http://www.laszlosystems.com/lps/viewer/viewer.jsp?file=/sample-apps/weather/weather.lzx

Does that answer your question?

-Antun

[mwalker]

Thanks for the response. I have already downloaded and begun creating apps with the presentation server - but the explorer is something new that I will definitely check out.

Getting back to my concen - Why, then, would any care to use swf files as an art asset. They obviously provide some animation capabilities (such as the word clock demo. I can tell that the shockwave program just spins the hour hand around and script is used to simply stop it at a given frame). Beyond animation, what do they provide?

For instance, the calendar and dashboard applications are very slick and I would love be able to use Laszlo to create similar utils. But would I be able to without learning shockwave?

( not that learning it would be a bad thing)

Regards,
-Matt

[antun]

You don't need to use SWFs at all to create a Laszlo app.

Why, then, would any care to use swf files as an art asset.

The reason you would use a SWF as an art asset is because SWF is a vector art format, so it stretches really well. This might be important if you're creating a window; the stretchy bits of the window chrome need to be able to stretch without distorting, so that would be a good place to use a SWF.

Also there are some situations where a particular art asset might be smaller in size when saved as a SWF, than a bitmap format (such as a GIF, JPEG or PNG).

Check out the window tutorial for more on that:

http://www.laszlosystems.com/developers/learn/documentation/tutorials/window.php


They obviously provide some animation capabilities (such as the word clock demo. I can tell that the shockwave program just spins the hour hand around and script is used to simply stop it at a given frame).


No that's not correct - the second hand is rotated purely through LZX. This part of the app moves the second hand:


this.shs.setAttribute('rotation',secNum*6,dur);
this.sh.setAttribute('rotation',secNum*6,dur);


-Antun