App.as

package
{
  import flash.display.Sprite;
	import flash.display.StageAlign;
	import flash.display.StageScaleMode;
	import flash.events.Event;
	import flash.geom.Rectangle;

	import starling.core.Starling;

	public class App extends Sprite
	{
		private var _starling:Starling;

		public function App()
		{
			if (stage) init();
			else addEventListener(Event.ADDED_TO_STAGE, init);
		}

		protected function init(event:Event = null):void
		{
			if (hasEventListener(Event.ADDED_TO_STAGE))
				removeEventListener(Event.ADDED_TO_STAGE, init);

			stage.scaleMode = StageScaleMode.NO_SCALE;
			stage.align = StageAlign.TOP_LEFT;

			stage.color = 0x000000;
			stage.frameRate = 60;

			_starling = new Starling(RodCalcApp, stage);
			_starling.start();

			stage.addEventListener(Event.RESIZE, onStageResize, false, int.MAX_VALUE, true);
			stage.addEventListener(Event.DEACTIVATE, onStageDeactivate, false, 0, true);
		}

		private function onStageDeactivate(event:Event):void
		{
			_starling.stop();
			stage.addEventListener(Event.ACTIVATE, onStageActivate, false, 0, true);
		}

		private function onStageResize(event:Event):void
		{
			if (stage.stageWidth < 256 || stage.stageHeight < 256) return;
			_starling.stage.stageWidth = stage.stageWidth;
			_starling.stage.stageHeight = stage.stageHeight;
			const viewPort:Rectangle = _starling.viewPort;
			viewPort.width = stage.stageWidth;
			viewPort.height = stage.stageHeight;
			try
			{
				_starling.viewPort = viewPort;
			}
			catch (error:Error)
			{

			}
		}

		private function onStageActivate(event:Event):void
		{
			stage.removeEventListener(Event.ACTIVATE, onStageActivate);
			_starling.start();
		}
	}
}