The following example shows how you can create a simple horizontal list using a HGroup container and do an animated scroll using the Animate and SimpleMotionPath classes and the getHorizontalScrollPositionDelta() method
Full code after the jump.
The following example(s) require Flash Player 10 and the Adobe Flex 4 SDK. To download the Adobe Flash Builder 4 beta, check out the Adobe Flash Builder 4 page on the Adobe Labs site. To download the latest build of the Flex 4 SDK, see http://opensource.adobe.com/wiki/display/flexsdk/Download+Flex+4. For instructions on using the beta Flex 4 SDK in Flex Builder 3, see "Using the beta Flex 4 SDK in Flex Builder 3".
<?xml version="1.0" encoding="utf-8"?> <!-- http://blog.flexexamples.com/2009/11/11/creating-an-animated-transition-when-scrolling-through-items-in-a-spark-hgroup-container/ --> <s:Application name="Spark_HGroup_horizontalScrollPosition_test" xmlns:fx="http://ns.adobe.com/mxml/2009" xmlns:s="library://ns.adobe.com/flex/spark" xmlns:mx="library://ns.adobe.com/flex/halo"> <fx:Script> <![CDATA[ import spark.core.NavigationUnit; protected function scrollToThere(dir:uint):void { var value:Number = hGr.getHorizontalScrollPositionDelta(dir); if (value != 0) { pth.valueBy = value; anim.play(); } } ]]> </fx:Script> <fx:Declarations> <s:Animate id="anim" target="{hGr}" duration="500"> <s:motionPaths> <s:SimpleMotionPath id="pth" property="horizontalScrollPosition" /> </s:motionPaths> </s:Animate> </fx:Declarations> <s:Panel title="HGroup horizontalScrollPosition test" horizontalCenter="0" verticalCenter="0"> <s:layout> <s:HorizontalLayout verticalAlign="middle" /> </s:layout> <s:Button label="<" click="scrollToThere(NavigationUnit.PAGE_LEFT);" width="30" /> <s:HGroup id="hGr" requestedColumnCount="3" columnWidth="100" variableColumnWidth="false" height="100" clipAndEnableScrolling="true"> <s:Label text="One" backgroundColor="red" backgroundAlpha="0.1" height="100%" /> <s:Label text="Two" backgroundColor="red" backgroundAlpha="0.2" height="100%" /> <s:Label text="Three" backgroundColor="red" backgroundAlpha="0.3" height="100%" /> <s:Label text="Four" backgroundColor="red" backgroundAlpha="0.4" height="100%" /> <s:Label text="Five" backgroundColor="red" backgroundAlpha="0.5" height="100%" /> <s:Label text="Six" backgroundColor="red" backgroundAlpha="0.6" height="100%" /> <s:Label text="Seven" backgroundColor="red" backgroundAlpha="0.7" height="100%" /> <s:Label text="Eight" backgroundColor="red" backgroundAlpha="0.8" height="100%" /> <s:Label text="Nine" backgroundColor="red" backgroundAlpha="0.9" height="100%" /> <s:Label text="Ten" backgroundColor="red" backgroundAlpha="1.0" height="100%" /> </s:HGroup> <s:Button label=">" click="scrollToThere(NavigationUnit.PAGE_RIGHT);" width="30" /> </s:Panel> </s:Application>
This entry is based on a beta version of the Flex 4 SDK and therefore is very likely to change as development of the Flex SDK continues. The API can (and will) change causing examples to possibly not compile in newer versions of the Flex 4 SDK.
{ 5 comments… read them below or add one }
Very nice, this is something I was looking for. Is there a way to loop to the beginning once you reach the end?
I did this, and it works:
protected function scrollToThere(dir:uint):void {
var value:Number = hGr.getHorizontalScrollPositionDelta(dir);
if (value != 0) {
pth.valueBy = value;
anim.play();
}
else
{
if(dir == NavigationUnit.PAGE_RIGHT)
{
value = hGr.getHorizontalScrollPositionDelta(NavigationUnit.HOME);
pth.valueBy = value;
anim.play();
}
if(dir == NavigationUnit.PAGE_LEFT)
{
value = hGr.getHorizontalScrollPositionDelta(NavigationUnit.END);
pth.valueBy = value;
anim.play();
}
}
}
but I was looking for a more continuous effect where it keeps going in the same direction.
Very nice done!! Thanxx!!
hmm.. how to make this animation play when mouse over on right or left items to right or left direction?
or mousewheel scrolling this items?
Can you do something similar with an entity that can have data bound to it, like a List?