Managing Animation State in GameObjects

/*
    This is an example of the simplest solution I can think off.
    My question is: are there any good standard solutions / practices / patterns
        to deal with animation states? Especially as they get more complex than two states
        I imagine this solution being way too unwieldy to maintain.


    _idleAnimation and _turnAnimation are both members of the GameObject,
        and children of its DisplayList.
*/
private function updateAnimationState(dx:Number):void
{
    if(Math.abs(dx) < 4)
    {
        start(_idleAnimation);
        stop(_turnAnimation);
    }
    else
    {
        stop(_idleAnimation);
        start(_turnAnimation);
        _turnAnimation.scaleX = (dx < 0) ? 1 : -1; //flip left/right
    }
}

//EDIT: http://gamedev.stackexchange.com/questions/27079/data-driven-animation-states seems like a well researched comment