public void materialComboBoxSelected() {
   try {
     selectedMaterial = matController.getMaterial(selectedMaterialID);
     editGRItem.setMaterial(selectedMaterial);
     if (selectedMaterial != null) {
       editGRItem.setReceiveUnit(selectedMaterial.getOrderUnit());
       editGRItem.setUnitPrice(selectedMaterial.getOrderUnitPrice());
     }
   } catch (ControllerException e) {
     FacesUtils.reportError(FacesContext.getCurrentInstance(), e.getMessage(), e.getMessage(), e);
     e.printStackTrace();
   }
 }