public enum ImageType
{
    None = 0,
    Png = 1,
    Jpg = 2,
    Gif = 3
}

public class ImageType
{
    public function ImageType() {}
    [Inspectable(category="Generated values", eumeration="None,Png,Jpg,Gif", type="String")]
    public var _ImageType:String;public function toString():String
    {
        return _ImageType.toString();
    }
}

var imgType:ImageType = ImageType.Png; //this does not actually work though

var imgType:ImageType = new ImageType();
imgType._imageType = "Png";