Commands of custom properties of the Writer are not executed


I’ve noticed that when I modify a custom writer property (other than the filename, padding or write frequency), the command associated with it (described in the XML file of the writer) will not be called in situ (Catalyst).

When I modify “filename” property, the corresponding command (writer class’s method) gets called. In the callstack, I can see the method PyvtkSMProxy_UpdateVTKObjects. But why this method is not executed for user’s custom properties ?

In the Python file (, I wasn’t able to locate the part which is related to commands.

With Wireshark, I saw that Paraviewn after clicking on “Apply”, sends an XML content to Catalyst (here : XML_Sample_PV_To_Catalyst_Apply_Btn.xml (8.2 KB)), I don’t know where this XML data get parsed, it contains all the property values of the writer.

I really need to modify this behavior, because right now I implemented a dirty solution to send commands the catalyst’s writer from Paraview.

Any informations is welcome.