[saf] Change step properties of type list/dict

Question

If a step class has a dict property my_dict, is looks like it is not possible to simply change this property in a callback my_dict["key"]="value". For every property you need top make a copy, modify the copy and then assign the step property. Creates 3 lines of code for every property to change .... looks very ugly. Any idea?

didier · Answer

You actually do not need to do the copy.

step.my_dict["key"]= "vlaue"

step.my_dict = step.my_dict

This is a bit strange, but ¯_(ツ)_/¯

Stefan Marth · Answer

yes, but I want to change just one entry in the dict and for that currently I have to do this:

tmp_dict = dict(step.my_dict)

tmp_dict['MyKey'] = 'MyValue'

step.my_dict = my_dict

because

step.my_dict['MyKey'] = 'MyValue'

is not working

didier · Answer

I do not think you need to make a copy, but you need to let the proxy know that the content of my_dict has changed: step.my_dict = my_dict  does the trick.