How to access a public function outside custom component in flex? - actionscript-3

Question

I have an application width a mx:ViewStack component with differents view components under each s:NavigatorContent as it follows.
<mx:ViewStack id="vsOne" resizeToContent="true">
<s:NavigatorContent label="First">
<package:MyFirstComponent id="myFirstComponent"/>
</s:NavigatorContent>
<s:NavigatorContent label="Second">
<package:MySecondComponent id="mySecondComponent"/>
</s:NavigatorContent>
</mx:ViewStack>
And this is package.MyFirstComponent's important part..
<s:Button label="Next" click="somethingToGoForward()"/>
What I've tried:
Calling somethingToGoForward() in the view component and triyng to access to a parent vsOne: Don't work.
Calling parent.somethingToGoForward() (when this method is in the same mxml as the ViewStack): Don't work
How can I change my ViewStack's selectedIndex from anywhere outside the mxml file containing it?
Thanks.

Answer 1

This is an example using simple events:
<?xml version="1.0" encoding="utf-8"?>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009" initialize="application1_initializeHandler(event)"
xmlns:s="library://ns.adobe.com/flex/spark"
xmlns:mx="library://ns.adobe.com/flex/mx" minWidth="955" minHeight="600" xmlns:local="*">
<fx:Script>
<![CDATA[
import mx.events.FlexEvent;
protected function application1_initializeHandler(event:FlexEvent):void
{
viewStack.selectedChild=one;
}
protected function one_changeViewHandler(event:FlexEvent):void
{
viewStack.selectedChild=two;
}
protected function two_changeViewHandler(event:FlexEvent):void
{
viewStack.selectedChild=one;
}
]]>
</fx:Script>
<fx:Declarations>
<!-- Place non-visual elements (e.g., services, value objects) here -->
</fx:Declarations>
<mx:ViewStack id="viewStack" >
<local:ccomp id="one" changeView="one_changeViewHandler(event)" text="LAbel ONE">
</local:ccomp>
<local:ccomp id="two" changeView="two_changeViewHandler(event)" text="LAbel TWO" >
</local:ccomp>
</mx:ViewStack>
</s:Application>
ccomp is a custom component
<?xml version="1.0" encoding="utf-8"?>
<mx:HBox xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark"
xmlns:mx="library://ns.adobe.com/flex/mx" width="400" height="300">
<fx:Metadata>
[Event(name="changeView", type="mx.events.FlexEvent")]
</fx:Metadata>
<fx:Script>
<![CDATA[
import mx.events.FlexEvent;
private var _text:String;
public function get text():String
{
return _text;
}
[Bindable]
public function set text(value:String):void
{
_text = value;
}
protected function button1_clickHandler(event:MouseEvent):void
{
this.dispatchEvent(new FlexEvent("changeView",true));
}
]]>
</fx:Script>
<fx:Declarations>
</fx:Declarations>
<s:Button label="Change" click="button1_clickHandler(event)">
</s:Button>
<s:Label fontSize="24" text="{text}">
</s:Label>
</mx:HBox>
Davide