treeGD.heightHint = 100;
// tableGD.minimumWidth = PREVIEWWIDTH;
treeControl.setLayoutData(treeGD);
rulesViewer.setContentProvider(new GroupRulesTreeContentProvider());
rulesViewer.setLabelProvider(new GroupRulesTreeLabelProvider(SLD.POLYGON));
rulesViewer.addSelectionChangedListener(new ISelectionChangedListener(){
private PolygonPropertiesComposite polygonPropertieComposite;