CODEWITHSUNDEEP
swift
Yousef humdan
Yousef humdan

Reputation: 67

access a variable outside a function - swift

I'm trying yo access a variable outside a function, I tried to declare the variable outside the class but it keeps displaying the initial value in the declaration not the value inside the function, here is my code, I need to access databaseScore

func getDatabaseScore()-> Int{
    let ref2 = FIRDatabase.database().reference().child("users").child("user").child((user?.uid)!)

    ref2.observeSingleEvent(of: .childAdded, with: { (snapshot) in
        if var userDict = snapshot.value as? [String:Int] {
            //Do not cast print it directly may be score is Int not string
            var databaseScore = userDict["score"]

        }


    })

    return databaseScore

}

Upvotes: 0

Views: 919

Answers (2)

vadian
vadian

Reputation: 285082

As mentioned in the comment it's impossible to return something form a method containing an asynchronous task.

You need a completion block for example

func getDatabaseScore(completion: (Int?)->()) {
    let ref2 = FIRDatabase.database().reference().child("users").child("user").child((user?.uid)!)

    ref2.observeSingleEvent(of: .childAdded, with: { (snapshot) in
        if let userDict = snapshot.value as? [String:Int] {
            //Do not cast print it directly may be score is Int not string
            completion(userDict["score"])
        }
        completion(nil)
    })
}

getDatabaseScore() { score in 
   guard let score = score else { return }
   // do something with unwrapped "score"
}

Upvotes: 1

Ashley Mills
Ashley Mills

Reputation: 53121

You're doing an async operation so getDatabaseScore returns before observeSingleEvent completes. You could look at something like this…

class MyClass {

    var databaseScore: Int = 0

    func getDatabaseScore() {

        let ref2 = FIRDatabase.database().reference().child("users").child("user").child((user?.uid)!)

        ref2.observeSingleEvent(of: .childAdded, with: { (snapshot) in                 
            if let userDict = snapshot.value as? [String:Int] { 
                 print(userDict["score"]) // Confirm you have the a value
                 self.databaseScore = userDict["score"]
             }
         }
    }

Upvotes: 1

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