Well -- not exactly how someone would imagine. You can build your GUI in any iOS, macOS, etc application within Xcode and add your view as a target of another platform. It's maybe not the best solution, but one that works :)
Which is a good thing! (author of this project here)
OpenSwiftUI is not meant to run on Apple devices. Quite the opposite :) The project is quite in the early stages but at some point, it should be possible to create graphical interfaces with GTK, Win32 Forms or even ASCII, but written in Swift.
"Learn once, apply anywhere."
Hey @DagAgren, author auf OpenSwiftUI:
Yeah, it's weird.
My plan is to stay as close to the SwiftUI API as possible.
However, I had to expose some private properties for the platform specific implementation like SwiftUIEmbedded and left the underscore to indicate that this property is not meant to be used by an application developer.
I don't like it either -- but that was the best I could come up with :)