public static void activate(Field masterField, RelatedGuiField relatedGuiField) { RequestComboBox comboBox = (RequestComboBox) masterField.getComponent(); RelatedFieldValueUpdater listener = new RelatedFieldValueUpdater(relatedGuiField, relatedGuiField.getComponent(), comboBox); comboBox.getDataSource().addPropertyChangeListener(DataSource.SELECTED_ROW_PROPERTY, listener); listener.updateValue(); }