def METHOD_NAME(self, param, changes):
    changes = [ch for ch in changes if ch[0] not in self._ignoreChange]
    #resets = [ch[0] for ch in changes if ch[1] == 'setToDefault']
    sets = [ch[0] for ch in changes if ch[1] == 'value']
    #for param in resets:
        #setattr(self._system, param.name(), None)
    for param in sets:
        #if param in resets:
            #continue
        #if param in self._fixParams:
            #param.parent().setWritable(param.value())
        #else:
        if param in self._fixParams:
            parent = param.parent()
            if param.value():
                setattr(self._system, parent.name(), parent.value())
            else:
                setattr(self._system, parent.name(), None)
        else:
            setattr(self._system, param.name(), param.value())
    self.updateAllParams()