How to set Default Delegate?

[avpmax]

I'm working with a WindowCoveringDevice cluster on esp32.
Since the GoToLiftPercentage command is not created by default,
I created it as a custom command and it worked fine.
However, since commands such as UporOpen, DownorClose, and Stop are created by default and cannot be deleted,
custom commands cannot be substituted.
So I want to implement the callback of the corresponding commands using SetDefaultDelegate.
However, delegate cannot be set because emberAfFindClusterServerEndpointIndex always returns 0xFFFF.

What is the procedure for registering SetDefaultDelegate?

[bzbarsky-apple]

Since the GoToLiftPercentage command is not created by default, I created it as a custom command and it worked fine.

How did you "create it as a custom command"? The command is optional, but can just be enabled in the ZAP configuration. Is that what you did? If not, what exact thing did you do, @avpmax ?

However, since commands such as UporOpen, DownorClose, and Stop are created by default and cannot be deleted,
custom commands cannot be substituted.

"substituted" in what sense? UpOrOpen is a mandatory command, so it has to be implemented, yes...

However, delegate cannot be set because emberAfFindClusterServerEndpointIndex always returns 0xFFFF.

That's because it's looking for Channel clusters for some reason, not Window Covering clusters. #24730 should fix that; nice catch!