[Pythonmac-SIG] Embedded Quartz Composer and cocoa notifications

[Ronald Oussoren]

On 22-jun-2006, at 11:31, Jonathan wrote:
>
> I get this error:
>
> Traceback (most recent call last):
>   File "/Volumes/Docs/Users/jonathan/svnCheckouts/main/scmac/trunk/ 
> QCPySight/QCPySightAppDelegate.py", line 54, in  
> applicationDidFinishLaunching_
>     self._observePatchController()
>   File "/Volumes/Docs/Users/jonathan/svnCheckouts/main/scmac/trunk/ 
> QCPySight/QCPySightAppDelegate.py", line 39, in  
> _observePatchController
>     self.patchController.addObserver_forKeyPath_options_context _ 
> (self, u"patch.Image.value", None, None)
>
> ValueError: depythonifying 'unsigned int', got 'NoneType'
> 2006-06-22 05:23:06.070 QCPySight[665] Exception raised during  
> posting of notification.  Ignored.  exception:  
> exceptions.ValueError: depythonifying 'unsigned int', got 'NoneType'
>
> I wonder if I'm translating the code in the tech note properly re:  
> adding an observer.  I'm pretty sure that I have the QC file setup  
> properly and that the bindings are all kosher.

The context is a void* in Objective-C, and should be an integer in  
Python. It isn't possible to use arbitrary objects as the context  
because as far as I know it is impossible to get memory management  
correct for that.

Ronald