[vtkusers] wxPython & VTK: How to Destroy wxVTKRenderWindow without errors?

[Kenneth Evans]

Charl,

>> Do you see now?

No.  I get an exception.  I also get an exception in the following line from
your original solution:

wxRWI.SetRenderWindow(None)

i.e. Exception destroying renWin
'wxVTKRenderWindow' object has no attribute 'SetRenderWindow'

OK, I think I see the problem. I typically use a vtkRenderWindow and not a
vtkRenderWindowInteractor.  I translated your fix to use wxVTKRenderWindow
(what I use).  It does not have that method.  vtkRenderWindowInteractor
apparently does, even though you can't find it through pattern searching.  I
am not exactly a Python guru and did not know about __getattr__.  So I
[somewhat] see, now.  Clever.  (But makes hard-to-follow code).

When I did use a vtkRenderWindowInteractor was in trying to modify the
cone6.py turorial example (VTK_DIR\Examples\Tutorial\Step6\Python) to use
WX.  That did not work:

a. If I modified it to use:

    iren.SetRenderWindow(self.renWin)

it fails with

    iren.SetRenderWindow(self.renWin)
ValueError: method requires a VTK object

(which is a different exception, sorry).

b. If I modify it to use:

  iren.SetRenderWindow(self.renWin.GetRenderWindow())

it doesn't get an exception, but it doesn't work right either.

c. If I just replace the wxVTKRenderWindow with a
wxVTKRenderWindowInteractor everywhere, it works fine.

I apologize that in doing all this trial and error, I may have got confused
about which class had what methods and what exceptions.

>> You're supposed to use either one or the other, not both.

So, that seems to work, once you know the rule.  However, the cone6.py
example (VTK_DIR\Examples\Tutorial\Step6\Python) doesn't do that.  (It's not
that I especially care about cone6.py, but it is a standard example that
everyone has.)

What happens when you have more than one interactor?

In any event I've learned a bit.  Thanks.  Sorry if I've been a pain in the
butt.

        -Ken