I can't resume preview canvas

[JIANG YI]

My environment is ok, as my new initial project with SwiftUI can resume preview canvas. But, in this project, I can't see preview canvas.

When I add below section:

#if DEBUG  
struct ContentView_Previews : PreviewProvider {  
    static var previews: some View {  
        SearchUserView()  
    }  
}  
#endif  

I got:

SwiftUI-Combine-Example.app: Error Domain=render service Code=12 "Rendering service was interrupted" UserInfo={NSLocalizedDescription=Rendering service was interrupted}

[Bruno Fernandes]

Are you using MacOS Catalina?

[Ryann786]

How did you resolve this?