RxSwift practice to show/hide ActivityIndicator - ios

Question

Let's say we have this pseudocode representing a network request call and show/hide an activity indicator, using RxSwift:
func performRequest() {
isLoading.accept(true)
self.network.executeRequest()
.subscribe(onNext: {
self.isLoading.accept(false)
}, onError: {
self.isLoading.accept(false)
})
}
The function executeRequest returns either an Observable or Single.
I am not feeling comfortable with having to write twice the same code, for onNext/onSuccess and onError, basically doing the same.
I am looking for suggestions to minimize/improve turning off the activity indicator, like for example handling all events of the request in a single statement and avoid using the subscribe function. Or maybe there are other suggestions?

Answer 1

I use ActivityIndicator from RxSwift Example app, which makes it really convenient, especially if your loading multiple things in parallel as it maintains a count of running subscriptions and emit false only when this count is equal to 0:
let isLoading = ActivityIndicator()
func performRequests() {
self.network
.executeFirstRequest()
.trackActivity(isLoading)
.subscribe {
// ...
}
self.network
.executeSecondRequest()
.trackActivity(isLoading)
.subscribe {
// ...
}
}

Answer 2

You can use another method to subscribe, which passes Event in case of Observer or SingleEvent in case of Single:
subscribe(on: (Event<T>) -> Void)
subscribe(observer: (SingleEvent<T>) -> Void)
Observer Example:
func performRequest() {
isLoading.accept(true)
self.network.executeRequest().subscribe {
switch $0 {
case let .error(error):
print(error)
case let .next:
print("good")
case .completed:
print("also good")
}
isLoading.accept(false)
}
}
Single Example:
func performRequest() {
isLoading.accept(true)
self.network.executeRequest().subscribe {
switch $0 {
case let .error(error):
print(error)
case let .next:
print("good")
}
isLoading.accept(false)
}
}