Now the current object(s) selected in the OB is (are) set into the widget when the button is clicked.

src/StdMeshersGUI/StdMeshersGUI_ObjectReferenceParamWdg.cxx

@@ -153,6 +153,7 @@ void StdMeshersGUI_ObjectReferenceParamWdg::activateSelection()
     connect(mySelectionMgr, SIGNAL(currentSelectionChanged()), SLOT(onSelectionDone()));
   }
   emit selectionActivated();
+  onSelectionDone();
 
   mySelButton->setChecked( mySelectionActivated );
 }

src/StdMeshersGUI/StdMeshersGUI_ObjectReferenceParamWdg.h

@@ -126,7 +126,6 @@ private:
  QString                myParamValue;
  QString                myEmptyText;
  QString                myEmptyStyleSheet;
- //int                    spacing;
 };
 
 #endif // STDMESHERSGUI_OBJECTREFERENCEPARAMWDG_H