Reputation: 144
I am trying to fetch all users into an array and use callback when this is done. I need to know when the fetching is complete. I have understood that this might not work as i thought with childAdded so i am trying with observeSingleEvent but i am having problems to fetch into the array. Any ideas why?
This code with childAdded works with putting the data to the array but not the completion even if i put it inside.
self.ref?.child("Users").observe(DataEventType.childAdded, with: { (snapshot) in
// Fetch users
if let dictionary = snapshot.value as? [String: AnyObject] {
let user = User()
user.nameLabel = dictionary["Username"] as? String
user.occupationLocation = dictionary["Occupation"] as? String
user.ageLabel = dictionary["Age"] as? String
user.infoText = dictionary["Bio"] as? String
user.emailText = dictionary["email"] as? String
let email = user.emailText
let ref = Database.database().reference().child("Users")
ref.queryOrdered(byChild: "email").queryEqual(toValue: email).observeSingleEvent(of: .childAdded, with: { (snapshot) in
user.toId = snapshot.key
})
self.usersArray.append(user)
}
})
//dump(self.usersArray)
completion("FetchAllUsersKlar")
This code does not work at all:
self.ref?.child("Users").observeSingleEvent(of: .value, with: { (DataSnapshot) in
// Fetch users
if let dictionary = snapshot.value as? [String: AnyObject] {
let user = User()
user.nameLabel = dictionary["Username"] as? String
user.occupationLocation = dictionary["Occupation"] as? String
user.ageLabel = dictionary["Age"] as? String
user.infoText = dictionary["Bio"] as? String
user.emailText = dictionary["email"] as? String
let email = user.emailText
let ref = Database.database().reference().child("Users")
ref.queryOrdered(byChild: "email").queryEqual(toValue: email).observeSingleEvent(of: .childAdded, with: { (snapshot) in
user.toId = snapshot.key
})
self.usersArray.append(user)
}
completion("FetchAllUsersKlar")
})
Firebase looks like this:
Upvotes: 0
Views: 181
Reputation: 372
This is the User struct:
struct User{
var id:String
var username:String?
var occupation:String?
var age:Int?
var bio:String?
var email:String?
}
Here's the firebase query, although I believe that decoding object through Codable is much better, but for the sake of sticking with your example I parsed the object with keys.
let query = self.ref.child("Users").queryOrdered(byChild: "email")
query.observeSingleEvent(of: .value) {
(snapshot) in
for child in snapshot.children.allObjects as! [DataSnapshot] {
let id = child.key
let value = child.value as? NSDictionary
let username = value?["Username"] as? String
let occupation = value?["Occupation"] as? String
let age = value?["Age"] as? Int
let bio = value?["Bio"] as? String
let email = value?["email"] as? String
let user = User(id: id, username: username, occupation: occupation, age: age, bio: bio, email: email)
self.usersArray.append(user)
}
completion("Users list fetched")
}
Upvotes: 2