When useVirtualLayout=true, renderers are being recycled so more invalidation does go on. It pretty much has to. You might be able to block some of it, depending on your scenario.
On 8/9/10 12:12 AM, "Florian" <[email protected]> wrote: When scrolling my custom item renderer, which inherits from ItemRenderer, i notice significant performance problems, when scrolling the list. It seems like the list's layout is invalidating the component when the list is scrolled. I configured the list's layout with the following parameters: <s:VerticalLayout gap="0" horizontalAlign="contentJustify" paddingBottom="0" paddingLeft="0" paddingRight="0" paddingTop="0" rowHeight="82" useVirtualLayout="true", variableRowHeight="false" /> I also overwrote the renderer's measuredWidth and measuredHeight properties: override public function set measuredHeight(value:Number):void { height = super.measuredHeight = value; } override public function set measuredWidth(value:Number):void { width = super.measuredWidth = value; } The question for me now popping up is, how to avoid those unnecessary invalidation cycles? I'd expect the layout to be at least as smart as handling size changes only when the item renderer's owner changes it's width, since the rowHeight is set. Best regards -- Alex Harui Flex SDK Team Adobe System, Inc. http://blogs.adobe.com/aharui
