Apache Pivot's Hello World Tutorial in Groovy

The following is a port of the JavaScript example on http://pivot.apache.org/tutorials/hello-wtkx.html to Groovy.
 
Note : I could not get 
 
def windowOpened(window){
 
to work, so that is why I use a closure instead.
 
 

<Window title="Hello JavaScript!" maximized="true"
    xmlns:wtkx="http://pivot.apache.org/wtkx"
    xmlns="org.apache.pivot.wtk">
    <windowStateListeners>
        <wtkx:script language="groovy"><![CDATA[
        import org.apache.pivot.wtk.*;
        windowOpened = { window ->
            def label = new Label();
            label.setText("Hello Groovy!");
            label.getStyles().put("font", "Arial BOLD 24");
            label.getStyles().put("color", "#ff0000");
            label.getStyles().put("horizontalAlignment", HorizontalAlignment.CENTER);
            label.getStyles().put("verticalAlignment", VerticalAlignment.CENTER);
            window.setContent(label);
        }
        ]]></wtkx:script>
    </windowStateListeners>
</Window>