Something

import flash.desktop.NativeDragManager;
import flash.events.NativeDragEvent;
import flash.desktop.ClipboardFormats;

var imageLoader:Loader = new Loader();
dropBox.addChild(imageLoader);

this.addEventListener(NativeDragEvent.NATIVE_DRAG_ENTER, onDragEnter);
this.addEventListener(NativeDragEvent.NATIVE_DRAG_DROP, onDragDrop);

function onDragEnter(e:NativeDragEvent):void{
	var fa:Object = e.clipboard.getData(ClipboardFormats.FILE_LIST_FORMAT);
	if(fa[0].extension=="jpg"){
		NativeDragManager.acceptDragDrop(this);
	}
}

function onDragDrop(e:NativeDragEvent):void{
	var fa:Object = e.clipboard.getData(ClipboardFormats.FILE_LIST_FORMAT);
	imageLoader.load(new URLRequest(fa[0].url));
}