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swiftwatchkitinit

Error: "cannot invoke initializer" for function to be executed on Watch OS only

I declared a failable initializer in my 'HealthKitService' which is, as the name says, a utility class for HealthKit. The problem is that certain HealthKit classes such as HKWorkoutSession, are available for Watch OS only, so I had to use a preprocessor directive to make a function available for Watch OS only: 

#if TARGET_OS_WATCH
init?(activity:String) {
    // Here I initialize my HKWorkoutSession object
}
#endif

But if I call this initializer from the WatchKit extension app, this way:

if let service = HealthKitService(activity: activity) {
    // Do something with it
}

I receive this error:

Cannot invoke initializer for type 'HealthKitService' with an argument list of type '(activity: String)'

PS: The deployment target is Watch OS 3.2, Swift version: 3.

Solution

  • Try #if os(watchOS) instead of #if TARGET_OS_WATCH.