@Override
    public void read(JmeImporter im) throws IOException {
        super.read(im);
        InputCapsule ic = im.getCapsule(this);
        screen = ic.readString("screen", "");
    }
De-serialize this event, for example when loading from a J3O file.

@param im importer (not null)
@throws IOException from importer
jme3-niftygui/src/main/java/com/jme3/cinematic/events/GuiEvent.java