[FLEX-22243] horizontalScrollPosition of a TileList does not dispatch the correct value when liveScrolling is set to false

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: Adobe Flex SDK 3.3 (Release)
• Component/s: mx: TileList
• Environment: Affected OS(s): All OS Platforms; Affected OS(s): All OS Platforms; Language Found: English
• Assignee: Unassigned
• Reporter: Adobe JIRA
• Created: 02/Dec/09 04:01
• Updated: 02/Dec/09 04:01

Description

Consider the following code:

<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute" height="100%" width="100%"
creationComplete="handleCreationComplete()">

<mx:Script>
<![CDATA[
import mx.collections.ArrayCollection;

[Bindable] private var dummyData : ArrayCollection;

private function handleCreationComplete() : void
{
dummyData = new ArrayCollection();
for (var i:int = 0; i<2000; i++)

{ dummyData.addItem( "Data " + i ); }

}
]]
>
</mx:Script>

<mx:VBox height="100%" width="100%">
<mx:Label width="100%" height="25" textAlign="center" text="Scroll:

{tileList.horizontalScrollPosition}

"/>
<mx:TileList id="tileList" width="100%" height="100%" direction="vertical" selectable="false"
horizontalScrollPolicy="on" verticalScrollPolicy="off" liveScrolling="false" columnWidth="100"
dataProvider="

{dummyData}

" />
</mx:VBox>
</mx:Application>

Steps to reproduce:
1. Compile the above code
2. Scroll Horizontally using the Scroll Bar
3. Observe the value on the top of the screen

Actual Results:

The actual value is the previous horizontal scroll position

Expected Results:

The current horizontal scroll position

Workaround (if any):

The bug is located within ScrollControlBase.scrollHandler

protected function scrollHandler(event:Event):void
{
// TextField.scroll bubbles so you might see it here
if (event is ScrollEvent)

{ var scrollBar:ScrollBar = ScrollBar(event.target); var pos:Number = scrollBar.scrollPosition; var prop:QName; if (scrollBar == verticalScrollBar) prop = new QName(mx_internal, "_verticalScrollPosition"); else if (scrollBar == horizontalScrollBar) prop = new QName(mx_internal, "_horizontalScrollPosition"); dispatchEvent(event); if (prop) this[prop] = pos; }

dispatchEvent dispatches the ScrollEvent which triggers the Binding update for horizontalScrollPosition, however _horizontalScrollPosition is not updated until the next line, hence the Binding update recieves the previous value