[FLEX-24052] Scrolling Spark Scroller using mouse wheel doesn't dispatch a change event on the VScrollBar

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: Adobe Flex SDK 4.5 (Release)
• Fix Version/s: Adobe Flex SDK Previous
• Component/s: Spark: Scroller
• Environment: Affected OS(s): All OS Platforms; Language Found: English
• Assignee: Adobe JIRA
• Reporter: Adobe JIRA
• Created: 25/May/10 10:05
• Updated: 10/May/11 13:48
• Resolved: 24/Jan/11 06:34

Description

Found in 4.5.0.16296.

Steps to reproduce:
1. Compile and run attached MXML file.
2. Scroll the s:Scroller using the increment/decrement buttons (change event is dispatched).
3. Scroll the s:Scroller by dragging the VSB thumb (change event is dispatched).
4. Scroll the s:Scroller by clicking on the VSB track (change event is dispatched).
5. Scroll the s:Scroller by using the mouse wheel (NO change event is dispatched)!

Actual Results:
VSB/Scroller isnt dispatching a change event when the VSB value is changed using the mouse wheel.

Expected Results:
change events.

Workaround (if any):
Instead of trying to listen for a "change" event on the VScrollBar, you can try listening for a "propertyChange" event on the viewport and then filter based on properties.

<?xml version="1.0" encoding="utf-8"?>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark"
xmlns:mx="library://ns.adobe.com/flex/mx">

<fx:Script>
<![CDATA[
import mx.events.PropertyChangeEvent;

protected function vsb_propertyChangeHandler(evt:PropertyChangeEvent):void {
switch (evt.property)

{ case "verticalScrollPosition": debbie.appendText(evt.newValue + " of " + evt.currentTarget.height + "\n"); break; }

}

protected function scr_creationCompleteHandler(evt:Event):void

{ scr.viewport.addEventListener(PropertyChangeEvent.PROPERTY_CHANGE, vsb_propertyChangeHandler); }

]]
>
</fx:Script>

<s:HGroup x="20" y="20">
<s:Scroller id="scr" width="100" height="100" creationComplete="scr_creationCompleteHandler(event);">
<s:Group>
<s:Rect width="100%" height="200">
<s:fill>
<s:LinearGradient rotation="45">
<s:GradientEntry color="Red" />
<s:GradientEntry color="Blue" />
</s:LinearGradient>
</s:fill>
</s:Rect>
</s:Group>
</s:Scroller>

<s:TextArea id="debbie" editable="false" />
</s:HGroup>

</s:Application>