I finally got around to using Flex framework caching on all my apps. Here’s a few little snags I ran across:

Don’t assume it works everywhere
Suppose you set up a project to use framework caching. You publish. You notice that your SWF is way smaller than before. ( Rejoice ) You upload your files, everything seems to work and you call it a day.

The problem is that you probably already have the Flex framework cached. So if it isn’t working you won’t know about it. I found this out by asking my wife to look at something I did with Flex and noticed that she got an error on the Flex preloader that said, “rsl error 1 of 1″.

My problem was that the Flex app was in a WordPress post and so the SWC files were not located in the same folder as the SWF. All I had to do was upload the framework_3.0.0.477.swf and framework_3.0.0.477.swz files to the root of my site. Problem solved.

If you want/need to delete your cached framework files for testing purposes then just go to the Global Storage Settings panel page and uncheck the Store common Flash components to reduce download times option. ( Usability note: I really wish there were a submit button or something on that panel. )

Lets see, what else went wrong? Well, nothing really. It was amazingly simple to implement. Makes me wish I’d done it years ago. Well, at least when it became available. Seems like years ago now. :-)

All I had to do was add -static-rsls=false to my command line and drop the SWC/SWZ files into my html-template folder. That was pretty much it.

You can read more about the Framework RSL at Adobe.

Addendum: I just added this post about framework caching for Flash Player 10.

While writing the code for the previous post I ran into a problem: my browser kept crashing when I’d publish my Flex project. All that was happening was that a <mx:Button> and <mx:TextArea> were fading in-and-out using <mx:Fade>.

Sure enough, it would cycle through about 4 times and start getting all jittery and then kaboom! Down goes the browser.

All that’s happening, in this example, is that when you click the top button it starts the other two buttons sliding back and forth. When one <mx:Move> is complete it calls an onTweenLeftEnd which starts the tween to the right. Back and forth we go.

If instead you use <mx:Fade> to fade the buttons in-and-out you get the same result. This doesn’t happen if you move or fade just one <mx:Button>. And it seems to happen with any two UIComponents.

Sometimes I feel that I suffer so that the rest of you don’t have to. When I run across one of those maddening, “but this should work” issues I always try to blog about it so that you – the reader – won’t have to suffer as I have. And I have, suffered greatly today. :-)

Here to the right we have two nearly identical Flex projects. The only difference is that the one on bottom has one line commented out of the CSS: fontWeight: normal;

It turns out that if you want to embed the font for a <mx:Button> you need to set the fontWeight. Yeah, it took me about 2 hours of trial and error to fix it. What really got me was that the embedding worked fine for the <mx:TextArea> all along. Go figure.

That’s it. So why does the fontWeight have to be “normal” in order for the <mx:Button> to get it’s embeded font? In the immortal words of Kyle Reese, “I don’t know. I didn’t build the fucking thing!”

Seriously, why does there have to be a declaration that the fontWeight has to be normal? Isn’t that the default? And yes, changing it to bold breaks it.

Perhaps I’m missing something. Perhaps the Flex team isn’t out to confuse and confound me on a daily basis. If so please enlighten me in the comments. Until then I’m just going to assume that Deepa did this just to drive me mad. Mad I say. Mad, mad, MAD! :-)

I got stuck on a problem the other day using E4X. I was simply trying to get a Boolean value out of an attribute. It seemed to me that I could simply say:

setAutoPlayVideo( p.@autoPlayVideo );

Where autoPlayVideo is an attribute with a value of either “true” or “false”.

I expected E4X to type the variables I was using because I hadn’t needed to cast any of the attributes that were Strings or Numbers. Those all worked fine. After debugging a bit I discovered that each attribute was actually typed as XML. I’m a bit spoiled by my PXP2 class which automatically types values as Number, Boolean or String.

In the case of E4X and Booleans it was simple enough to fix once I understood what was going on. This does the trick:

var b:Boolean = ( p.@autoPlayVideo == "true" ) ? true : false;
setAutoPlayVideo( b );

Or if you’re not used to the ternary operator

var b:Boolean
if( p.@autoPlayVideo == "true ) {
b = true;
} else {
b = false
}
setAutoPlayVideo( b );

So I’m writing this Flex widget/app/thingy that will let people vote for things on my site. I need to test that the user has selected one of the radio buttons when they hit the submit vote button. The code for that is:

Pretty simple stuff. In the if-statement I’m essentially saying, “if votingChoices.selectedValue DOESN’T exist then do this stuff, else do this other stuff.

Like I said, simple. Right?

But there’s a catch. I wasn’t paying attention and gave the radioButtons data values of, wait for it, numbers starting with zero. And you know what that means: no one will be able to submit the first choice in the list.

Okay, so simple fix. I shouldn’t use numbers, especially starting with zero, for the radioButton values.

But better yet I could just change the if-statement to:

if( votingChoices.selectedValue == null ) { ...

That would be the smart thing to do. And I tell myself that all the time. Don’t test for the existence of something in an if statement by just placing a reference. Go ahead and write out undefined or null. Because that’s what you’re really testing.

I can’t count the number of times I’ve screwed that up. So now every time I do that I’ll force myself to come back to this post and comment that no I can’t learn from my mistakes. :-)

So here are a few other things that equate to false. From Moock’s Essential ActionScript 3.0.

Here is a table of the default values for the various types.