Hi Vipin.
I had a similar question, and Bastian answered as follows:
If you want to change the parameter while the flow graph is running (through a slider in the GUI, for example), you will have to extend the block with a callback.You could have a look at the Frame Equalizer block, for example. It allows changing the algorithm during run-time.To extend the block you have to:- add the callback function to the XML description of the block: (see here https://github.com/bastibl/gr-ieee802-11/blob/next/grc/ieee802_11_frame_equalizer.xml#L9)- implement the callback for the block (note that the callback is a public function that has also to be added to the definition in /include/, and the use of a mutex since ‘work’ and the callback are called in different thread contexts).
As Bastian said, you can't modify the parameters from the GUI if they don't have a callback function.
Best regards,
Cristian