+const static char* WDG_POINT2D_DISTANCE = "point2ddistance";
+
+const static char* WDG_FEATURE_SELECTOR = "feature_selector";
+const static char* WDG_FEATURE_OR_ATTRIBUTE_SELECTOR = "feature_or_attribute_selector";
+const static char* WDG_DOUBLEVALUE_EDITOR = "doublevalue_editor";