CODEWITHSUNDEEP
iosswiftfirebasefirebase-realtime-database
Justin Oroz
Justin Oroz

Reputation: 659

Initialized variable: 'self' captured by a closure before all members were initialized

I'm having issues with initialization of a custom class. I need to set up an observer on some data when the class is initialized which updates properties. Initially, the properties can be empty and that is how I set them at initiation. However, Xcode still throws the "'self' captured by a closure before all members were initialized" error. Here is a shortened version of the code.

class Foo {
    init() {
        self.usersRef = ref.child("users")
        self.usersRef.observe(DataEventType.value, with: { (snapshot) in
            // snapshot error checking
            // users is [String]

            self.users = users
        })
    }

    private var usersRef: DatabaseReference
    private(set) var users: [String] = []

}

I have also tried 

class Foo {
    init() {
        self.users = [String]()
        self.usersRef = ref.child("users")
        self.usersRef.observe(DataEventType.value, with: { (snapshot) in
            // snapshot error checking
            // users is [String]

            self.users = users
        })
    }

    private var usersRef: DatabaseReference
    private(set) var users: [String]

}

to ensure initialization prior to the callback.

From this question it seemed I only needed to give the properties initial values, but this does not seem to be the case. I would prefer not to have to call another function to set up these handlers after initialization.

Thank you for an help

Upvotes: 4

Views: 3366

Answers (1)

Vyacheslav
Vyacheslav

Reputation: 27211

Try to use this block 

 { [unowned self] (snapshot) in
            // snapshot error checking
            // users is [String]

            self.users = users
        })

or 

{ [weak self] (snapshot) in
            // snapshot error checking
            // users is [String]

            self?.users = users
        })

Upvotes: 3

Related Questions