If I haven't bored you yet, I would love to tell you
exactly what the issue is. For a long time now we've
occasionally seen very strange behavior. As I
described before, you'll write something, get
everything working perfectly, then do a clean build
before deploying and suddenly something disappears.
The problem is clearly that some properties are not
being initialized properly. I can make it happen
regularly and predictably right now. I do a clean
build, and one component's x & y are not set, so they
show up in the upper left. Then I "touch" that file
(I put the line "if (false) true;" in it), and now it
works.
There are two theories here in the office. One is
that there is a compiler bug in flex so that bindings
are not always properly recognized. That's the old
pre-me theory.
My theory is that there is no problem with flex, but
that we are not properly initializing variables, and
that certain changes get made during initialization
"under the radar" of the binding mechanism.
First, it is easy to mistakenly break binding:
<MyFirstObject initialize="handleInit()" >
<mx:Script>
public var innerWidth: Number;
public function handleInit() {
innerWidth=myOtherObject.otherWidth;
}
</mx:Script>
<mx:Image width="{innerWidth}" />
</MyFirstObject>
<MyOtherObject initialize="handleInit()" >
<mx:Script>
public var otherWidth: Number;
public function handleInit() {
otherWidth=55;
}
</mx:Script>
</MyOtherObject>
Width in the Image component is properly bound to
innerWidth--any time innerWidth changes, so should
width. The problem is, innerWidth only changes one
time, in handleInit, when it is set, not bound,
to MyOtherObject.otherWidth. If
MyFirstObject.handleInit() is called before
MyOtherObject.handleInit(), innerWidth will be
undefined, and never changed again.
The second issue, I believe, is that the bindings are
only executed at a particular time during the
initialization process. (Specifically, in
constructObject2, after createChildren.) It is
possible, as I said, to get that out of order so that
the binding mechanism "fires" too soon, and not again.
So anyway, those are the two competing theories around
here: compiler bug, or subtleties in initialization
order that we do not appreciate.
Either way, I believe it is clear that binding is not
as robust as we'd wish, during initialization. And at
any rate, understanding better how something works is
always a good thing!
Greg
--- JesterXL <[EMAIL PROTECTED]> wrote:
> 2 things to do to ensure you're not nuts.
>
> 1. Add &recompile=true to the end of the URL string.
> Slows compiling, but
> it's worth the piece of mind.
>
> 2. Delete generated everytime you want to be sure
> your changes are in fact
> taking. Mine's here for Flex 1.5:
>
C:\JRun4\servers\starExhibits\cfusion-ear\cfusion-war\WEB-INF\flex\generated
>
> LOL!!!! Royal... AWESOME. Whew, that made my
> Thursday. Mmmm, tasty
> burger!!!!
>
> First off, bindings are supposed to free you from
> initialization worries.
> Here's how it was in Flash:
> - capture data in member var
> - create asset
> - wait a frame
> - set data
> - delete member var
> - repeat process in convulted way
>
> In Flex? Bind value in View and it'll "work" when
> she's created. Pimp!
>
> I'm sorry to hear it's not working that way for you.
> Here's the rundown.
>
> - init
> - createChildren
> - initial drawing
> * initialize is before everything is done drawing
> - createChildren is the last event fired when
> everyone and their mom is
> ready
>
> There is a good rundown of this on Adobe's DevNet
> site. If you want the
> link, I can go find; it's a pretty good explanation.
>
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