Re: why does my MXML act differently than my AS?

> I have a test program that, as far as I can tell, does the same thing using
> an MXML component and the equivalent actionscript.  When I click on the
> button to execute the AS version, everything is fine.  But when I click on
> the button to execute the MXML version, I get a layout flicker.  It's bad
> enough that if you try to click on the MXML button over and over really
> fast, you'll wind up clicking the main app and the menu will go away.
> Here's the code:
>
>
> <?xml version="1.0" encoding="utf-8"?>
> <Application
>   xmlns="http://www.adobe.com/2006/mxml"
>   layout="absolute"
>   >
>   <Script>
>     <![CDATA[
>       import mx.containers.GridItem;
>       import mx.controls.Label;
>       import mx.controls.DateField;
>       private function addCategoryAS():void
>       {
>         var gi:GridItem;
>         var gr:GridRow = new GridRow;
>
>         gi = new GridItem;
>         gr.addChild(gi);
>         gi.addChild(new Label);
>
>         addRow(gr);
>       }
>
>       private function addCategoryMXML():void
>       {
>         var gr:GridRow = new TestGridRow;
>         gr.initialize(); // this is just to try to make it equivalent -
> doesn't change flicker
>
>         addRow(gr);
>       }
>
>       private function addRow(gr:GridRow):void
>       {
>         grid.addChildAt(gr, 0);
>
>         var gi:GridItem;
>
>         gi = gr.getChildAt(0) as GridItem;
>         (gi.getChildAt(0) as Label).text = "item " + grid.numChildren +
> ":";
>
>         gr.validateSize(true);
>         var verticalGap:Number = grid.getStyle("verticalGap");
>         popup.scrollRect = new Rectangle(0, 0, Math.max(popup.width +
> gr.measuredWidth),
>             popup.height + gr.measuredHeight + (isNaN(verticalGap) ? 0 :
> verticalGap));
>         if (popup.localToGlobal(new Point(0, 0)).y <
> popup.owner.localToGlobal(new Point(0, 0)).y)
>           popup.y -= gr.measuredHeight + (isNaN(verticalGap) ? 0 :
> verticalGap);
>       }
>     ]]>
>   </Script>
>
>   <Canvas bottom="0">
>     <PopUpButton id="myPopupButton" openAlways="true">
>       <popUp>
>         <Canvas id="popup">
>           <Grid id="grid" paddingTop="4" paddingBottom="4" paddingLeft="4"
> paddingRight="4"
>             fontSize="12" backgroundColor="0xFFFFFF" borderStyle="outset"
> borderThickness="2"
>             >
>             <GridRow>
>               <GridItem>
>                 <Button label="Add AS" click="addCategoryAS()"/>
>                 <Button label="Add MXML" click="addCategoryMXML()"/>
>               </GridItem>
>             </GridRow>
>           </Grid>
>         </Canvas>
>       </popUp>
>     </PopUpButton>
>   </Canvas>
> </Application>
>
> TestGridRow.mxml:
> <?xml version="1.0" encoding="utf-8"?>
> <GridRow xmlns="http://www.adobe.com/2006/mxml">
>   <GridItem>
>     <Label/>
>   </GridItem>
> </GridRow>
>
>
> I've dug through the generated code and have not been able to find anything
> that I think would account for the problem.  This is frustrating, because
> what I really want to do is a more complicated MXML component to make it a
> lot nicer to add rows in my addCategory function.  But I can't as long as
> it's going to be so jittery.
>
> Thanks!
>
> --
> Jason
>