[Paraview] information_only property doesn't update, please help

[iusadhfoias sidufasipudf]

Hello VTK developers,
several questions about the correct usage of information_only properties
have been asked over the years, but I didn't find a working solution.

The attached example is a complete, tiny, source plugin ("MyInfoSource")
for paraview 5.4.1. It generates an empty PolyData output. I am only
interested in modifying and showing the source's properties.

MyInfoSource has 3 properties (cf. InfoSource.xml):
1) InputPoint allows to input three coordinates.
2) CalculatedPoint has 'information_only="1"' and will be calculated
whenever InputPoint is set.
3) ShowCalculatedPoint has 'information_property="CalculatedPoint"' and is
meant to output that calculated value.

I am using a modified vtkInfoSource::SetInputPoint, which sets the
CalculatedPoint coordinates to twice the InputPoint coordinates whenever
InputPoint changes (cf. vtkInfoSource.cxx).

I was expecting the "ShowCalculatedPoint" property to update in the
properties view, whenever I apply changes to InputPoint, but it doesn't
change. Only when I click "Restore application default setting values" for
MyInformationSource, then ShowCalculatedPoint shows twice the last value of
InputPoint.

Can you reproduce this behaviour?
What needs to be changed, so that ShowCalculatedPoint always shows twice
the InputPoint coordinates after changes are applied?

Many thanks,
Jussuf
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://public.kitware.com/pipermail/paraview/attachments/20180226/f8fd228d/attachment.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: InfoSource.zip
Type: application/zip
Size: 1970 bytes
Desc: not available
URL: <https://public.kitware.com/pipermail/paraview/attachments/20180226/f8fd228d/attachment.zip>