accessing a variable inside a closure from another function with swift - swift

Question

I am trying to create an app that lists certain services where users can rate each of the services. The rating from each server is saved in firebase database. I am able to retrieve all the ratings and calculate averages using the following function:
func observeStars() {
let placesRef = Database.database().reference().child("Review")
placesRef.observe(.childAdded, with: { (snapshot) in
let toId = snapshot.key
var total: Double = 0.0
var average: Double = 0.0
placesRef.child(toId).observeSingleEvent(of: .value, with: { (snapshot) in
let count = snapshot.childrenCount
for childOfPlace in snapshot.children {
let childOfPlaceSnap = childOfPlace as! DataSnapshot
let dict = childOfPlaceSnap.value as! [String: Any]
let val = dict["STAR"] as! Double
total += val
}
average = total/Double(count)
print(average)
})
}, withCancel: nil)
}
As you can see, the average is printed within 2 consecutive closures inside the function. However, I am having trouble using these average values in another function in a separate swift file, so I can use it to show the average ratings in each tableViewcell representing each service. My big question is how do I bring the calculated average value outside of the observeStars() function and use it somewhere else? Any input would be very much appreciated!

Answer 1

var average: Double = 0.0
func observeStars() {
let placesRef = Database.database().reference().child("Review")
placesRef.observe(.childAdded, with: { (snapshot) in
let toId = snapshot.key
var total: Double = 0.0
placesRef.child(toId).observeSingleEvent(of: .value, with: { (snapshot) in
let count = snapshot.childrenCount
for childOfPlace in snapshot.children {
let childOfPlaceSnap = childOfPlace as! DataSnapshot
let dict = childOfPlaceSnap.value as! [String: Any]
let val = dict["STAR"] as! Double
total += val
}
self.average = total/Double(count)
print(average)
})
}, withCancel: nil)
}