ClassyBaseMediator.as

package
{
	public class BaseMediator extends Mediator
	{
		[Inject]
		public var signalBus:ApplicationSignalBus;
		
		[Inject]
		public var styleController:StyleController;
		
		protected var _view:BaseView;
		
		public function BaseMediator()
		{
		}
		
		override public function onRegister():void
		{
			signalBus.stylesheetChanged.add(stylesheetChangedHandler);
		}
		
		protected function stylesheetChangedHandler(stylesheet:IStyleSheet):void
		{
			styleController.applyStyle(_view, stylesheet.getStyle('.ExtendingView'));
		}
	}
}

ClassyExtendingMediator.as

package
{
	public class ExtendingMediator extends BaseMediator
	{
		public function ExtendingMediator()
		{
		}
		
		public function get view():ExtendingView
		{
			return _view as ExtendingView;
		}
		
		[Inject]
		public function set view(value:ExtendingView):void // <-- Classy!
		{
			_view = value;
		}
		
		override public function onRegister():void
		{
			super.onRegister();
		}
	}
}

GhettoBaseMediator.as

package
{
	public class BaseMediator extends Mediator
	{
		[Inject]
		public var signalBus:ApplicationSignalBus;
		
		[Inject]
		public var styleController:StyleController;
		
		public function BaseMediator()
		{
		}
		
		override public function onRegister():void
		{
			signalBus.stylesheetChanged.add(stylesheetChangedHandler);
		}
		
		protected function stylesheetChangedHandler(stylesheet:IStyleSheet):void
		{
			var view:ExtendingView = this['view'] as ExtendingView; // <-- Ghetto!
			
			styleController.applyStyle(view, stylesheet.getStyle('.ExtendingView'));
		}
	}
}