There is nesting (tree) in the published parameter 'Choice' that you can use a Tester or TestFilter on to build your logic. Basically, you create a case for each possible combination in a delimited list and then use the one you want.

http://docs.safe.com/fme/2020.2/html/FME_Desktop_Documentation/FME_Workbench/!Transformer_Parameters/adding_a_parameter.htm?Highlight=use tree

The other way is to use a series of testers to meet conditions. I use either one depending on the complexity of the data.

Alternatively, have a look at FME 2021 (currently in beta), where there is a lot of new functionality in this regard. Available here: https://www.safe.com/support/downloads/#beta

Thanks for yur answer but I'm not sure if I understood correctly.

Are you basicaly proposing to have everything inside one parameter with the provided choice of all possible combinations? Can you make a sample workspace that will help to understand better?

Anyway, I would like to keep all parameters and to disable one (or more) in the case when the parameter/s are not relvant in relation to values selected on other parameter/s.

One simple example is provided and explained earlier in the post but it can be much more complex case with many parameters and complex depandancise between them.

I just want to make things more user freindly when I create custom transformer or when I make a workspace for customers.

Thanks

as @david_r​ mentions. FME 2021 will include a new parameter builder tool that will allow this sort of inheritance. Watch for the 2021 What's Great webinars which should be on the schedule fairly soon

Webinar date has been confirmed 9th March 2021

Thanks!

I'm looking forward to seeing the webinar.