custom property widget doesn't show up

I want to display the DoubleVectorProperty with an exclusive group of QRadioButton, each of which reflects a double value, by paraview’s custom propertiesPanel mechanism.
Referring to example pqMyPropertyWidget from paraview source, I built my custom filter plugin and loaded the dll successfully(i.e. I didn’t encounter any errors nor warnings). However, after I applied my custom filter, the widget(which is a QGroupBox with several radiobuttons) I’m expectant of didn’t show up in the propertiesPanel, nothing there, without any errors being raised though. So I’m not sure which part of my plugin went wrong.
Here is my source file:
propertySrc.rar (3.3 KB)
Anyone please help me on this?

Thanks.

Yohsino.

I do not see anything wrong in your code. Put some trace in your widget constructor to see if it is actually created.