OC project to visionOS, how can I do?

My project is use OC, is a iOS App, and now I need make it to visionOS (not unmodified designed for iPhone). So a question one, how can I differentiate visionOS by code, need use macro definitions, otherwise, it cannot be compiled. The question two, have some other tips?or other question need I know? Thanks.

OC project to visionOS, how can I do?
 
 
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