[PyQt] QApplication.notify exception?

[Giuseppe Corbelli]

On 5/26/19 10:37 PM, Matic Kukovec wrote:
> Hi guys,
> 
> I have an application that runs without a problem on Windows, but on 
> Linux it shows this message on exit:
> 
>     |Qt has caught an exception thrown from an event handler. Throwing
>     exceptions from an event handler is not supported in Qt. You must
>     not let any exception whatsoever propagate through Qt code. If that
>     is not possible, in Qt 5 you must at least reimplement
>     QCoreApplication::notify() and catch all exceptions there.|
> 
> I added an exception handler to a sub-classed QApplication like so:
> 
>     class MyApplication(data.QApplication):
>                  def notify(self, obj, event):
>                      try:
>                          return super().notify(obj, event)
>                      except:
>                          print("Unexpected Error")
>                          traceback.print_exc()
>                          sys.stdout.flush()
>                          return False
> 
> and it prints:
> 
>     |Unexpected Error Traceback (most recent call last): File
>     "myfile.py", line X, in notify return super().notify(obj, event)
>     RuntimeError: wrapped C/C++ object of type QObject has been deleted|
> 
> Any ideas of how to solve this problem?

The first step is to get some more information regarding the exception 
trace. The exception traceback has tb_frame and tb_next attributes to 
build a frames stack. Each frame has its own frame.f_code.co_name, 
frame.f_code.co_filename, frame.f_lineno and local stack variables 
(frame.f_locals).

-- 
Giuseppe Corbelli