@Override
    public void read(JmeImporter im) throws IOException {
        super.read(im);
        InputCapsule ic = im.getCapsule(this);
        screen = ic.readString("screen", "");
    }
@author Nehon
@deprecated use GuiEvent instead
jme3-niftygui/src/main/java/com/jme3/cinematic/events/GuiTrack.java