ahillman3 on Stack Overflow wrote this (and won my hero of the day award); OK, the primary focus for your solution is the preloader attribute on a mobile application. See the preloader=”CustomSplashScreen” below:
< ?xml version="1.0" encoding="utf-8"?>
The CustomSplashScreen extends and overrides the spark.preloaders.SplashScreen class, and the getImageClass function.
package
{
    import mx.core.DPIClassification;
    import mx.core.mx_internal;
import spark.preloaders.SplashScreen;
    use namespace mx_internal;
    public class CustomSplashScreen extends SplashScreen 
    {
        public function CustomSplashScreen()
        {
            super();
        } 
        override mx_internal function getImageClass(dpi:Number, aspectRatio:String):Class
        {
            return Class(splash);
        }
    }
}
The splash in the return Class(splash), is a simple fxg file, like so:
< ?xml version="1.0" encoding="UTF-8"?>
    
            
        
That’s all there is to it. Have fun!
— Allen
via .
