Python-GStreamer: Access class members inside callback function with fixed arguments

Question

I have a callback, that is provided by GStreamer-Python bindings which accepts fixed number of arguments. Here is the API : add_probe I call this function from inside a class function. Below is the pesudo code:

class Example:
   def __init__(self):
        thread = threading.Thread(target=self.run)
        thread.start()

   def run(self):
        #if external event
        self.idsrcpad = identity.get_static_pad("src")  #get source pad 
        self.idsrcpad.add_probe(Gst.PadProbeType.IDLE,self.modify_pipeline)


   def modify_pipeline(pad,info,self):
        #access self.idsrcpad
        self.idsrcpad.unlink(...)

Accessing self.idsrcpad, gives an error saying that idsrcpad is not a member of self.

The following question addresses, a similar issue, but then the callback function in the question does not have fixed number of arguments. In my case, the arguments are fixed for the callback function. Here is a more elaborate description of the add_probe function.

Can anyone suggest me what I am doing wrong here.

Answer 1

The correct syntax for the callback is :

 def modify_pipeline(self,pad,info):

With this new definition, self can be used inside the function.