All our projects use the same preloader. Like many people, we based our preloader on Jesse Warden’s tutorial.

Recently, it started doing funny by not centering. Google-ing around gave some hints, but none of them worked for me. Here is my solution.

Hide the preloader (line 6):

public override function set preloader(p:Sprite):void
{
_preloader = p;
p.addEventListener( ProgressEvent.PROGRESS , onSWFDownloadProgress );
p.addEventListener( FlexEvent.INIT_COMPLETE , onFlexInitComplete);
p.visible = false;
}

Use the ’stage’ property (see blog jaap kooiker). And unhide the preloader if we get a valid value for the stage width:

private function centerPreloader():void
{
if ((stage.stageWidth > 0) && (_preloader)) {
x = (stage.stageWidth / 2) - (clip.width / 2);
y = (stage.stageHeight / 2) - (clip.height / 2);
_preloader.visible = true;
}
}

Center the preloader on each progress event:

private function onSWFDownloadProgress( event:ProgressEvent ):void
{
centerPreloader();
updateProgressBar(event.bytesLoaded/event.bytesTotal);
}

It is probably a problem on my machine (Mac OSX 10.5), but if I use Arial as a font, I get incomplete rendering of strings. Text with fontWeight set to normal renders okay, but it only renders a few characters when fontWeight is set to bold.

global {
fontFamily: Arial;
}

It will only show the characters ‘aegknrsvw’. If I use Verdana, there is no problem.

Update 24 feb 2010:
I found out what caused the problem. In our Flash preloader, we embed some Arial characters:

And these embedded characters were exactly the only characters that were rendered correctly by the application. Once I removed the embedded characters, everything worked fine.