BaseCompositeChain.as

public class BaseCompositeChain extends AbstractChain implements IChain
{
	
	public function BaseCompositeChain( mode:String = ChainType.SEQUENCE, stopOnError:Boolean = true )
	{
		super( mode, stopOnError );
	}
	
	public function doProceed():void
	{
		if( currentStep is IAutonomousChainStep )
			IAutonomousChainStep( currentStep ).doProceed();
		else if( currentStep is IChain )
			IChain( currentStep ).start();
	}
}

EventChainExample.as

public function doEventChain() : void
{
	var eventChain : EventChain = new EventChain( dispatcher );
	eventChain.addEventListener( ChainEvent.CHAIN_COMPLETE, handleChainComplete, false, 0, true );
	eventChain.addStep( new EventChainStep( new UserEvent( UserEvent.USER_SCREEN_ACTIVE ) ) );
	eventChain.addStep( new EventChainStep( new UserEvent( UserEvent.USER_PROCESSING_COMPLETE ) ) );
	eventChain.start();
}

[EventHandler( event="UserEvent.USER_SCREEN_ACTIVE" )]
public function logUserScreenActive() : void
{
	// perform logic or dispatch events when the user screen is active
}

[EventHandler( event="UserEvent.USER_PROCESSING_COMPLETE" )]
public function logUserProcessingComplete() : void
{
	// perform logic or dispatch events when the processing finishes
}

public function handleChainComplete( event : Event ) : void
{
	// perform logic or dispatch events when the chain is complete
}

IAutonomousChainStep.as

public interface IAutonomousChainStep extends IChainStep
{
	function doProceed():void;
}

IChain.as

public interface IChain extends IEventDispatcher
{
	function get position():int;
	function set position( value:int ):void;
	
	function get isComplete():Boolean;
	
	function get stopOnError():Boolean;
	function set stopOnError( value:Boolean ):void;
	
	function hasNext():Boolean;
	function stepComplete():void;
	function stepError():void;
	
	function addStep( step:IChainStep ):IChain;
	
	function start():void;
	function doProceed():void;
}

IChainStep.as

public interface IChainStep
{
	function get chain():IChain;
	function set chain( value:IChain ):void;
	
	function get isComplete():Boolean;
	
	function complete():void;
	function error():void;
}