Swift Array Empty After Appending in Loop
0
I am appending user info from Firebase into an array but it seems like the array(usersArray) is empty in all prints after the loop. The array is declared outside the function. Any ideas why? Thank you.
func fetchAllUsers(completion: @escaping (_ message: String) -> Void){
//User or advertiser?
let uid = Auth.auth().currentUser?.uid
Database.database().reference(withPath: "Advertiser").child(uid!).observeSingleEvent(of: .value, with: { (snapshot) in
if snapshot.exists(){
myAdvertiserVar.advertiser = true
// Fetch all users
self.ref?.child("Users").observe(DataEventType.childAdded, with: { (snapshot) in
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) //This print is empty
completion("FetchAllUsers")
}
}
arrays swift firebase firebase-realtime-database
edited Nov 16 '18 at 5:34
PradyumanDixit
2,1872820
asked Nov 15 '18 at 18:43
olleolle
4929
|
show 3 more comments
0
I am appending user info from Firebase into an array but it seems like the array(usersArray) is empty in all prints after the loop. The array is declared outside the function. Any ideas why? Thank you.
func fetchAllUsers(completion: @escaping (_ message: String) -> Void){
//User or advertiser?
let uid = Auth.auth().currentUser?.uid
Database.database().reference(withPath: "Advertiser").child(uid!).observeSingleEvent(of: .value, with: { (snapshot) in
if snapshot.exists(){
myAdvertiserVar.advertiser = true
// Fetch all users
self.ref?.child("Users").observe(DataEventType.childAdded, with: { (snapshot) in
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) //This print is empty
completion("FetchAllUsers")
}
}
arrays swift firebase firebase-realtime-database
edited Nov 16 '18 at 5:34
PradyumanDixit
2,1872820
asked Nov 15 '18 at 18:43
olleolle
4929
stackoverflow.com/a/44490781/5009432. Reference this -- your difference and this is that you need to add the completion INSIDE your observe function, whereas it will know when it is done. Yours does not.
– impression7vx
Nov 15 '18 at 19:00
This did not solve it for me, It only produces prints until the looping has ended. Not only one single print and one completion message as i wish for. Do you know why?
– olle
Nov 15 '18 at 19:28
Yea, one sec. Gonna add answer.
– impression7vx
Nov 15 '18 at 19:31
stackoverflow.com/a/42615219/5009432. Here, this shows you how to determine when Firebase is done calling. You can't do it your way as you are . observing through each child, and you never know which 1 is the last.
– impression7vx
Nov 15 '18 at 19:41
1
You are missing the concept of "asynchronism". If you addprint("will append")just beforeself.usersArray.append(user), andprint("will call completion")just beforecompletion("FetchAllUsers")you'll see that the order of the output is not the one you think of...
– Larme
Nov 15 '18 at 19:48
|
show 3 more comments
0
0
0
I am appending user info from Firebase into an array but it seems like the array(usersArray) is empty in all prints after the loop. The array is declared outside the function. Any ideas why? Thank you.
func fetchAllUsers(completion: @escaping (_ message: String) -> Void){
//User or advertiser?
let uid = Auth.auth().currentUser?.uid
Database.database().reference(withPath: "Advertiser").child(uid!).observeSingleEvent(of: .value, with: { (snapshot) in
if snapshot.exists(){
myAdvertiserVar.advertiser = true
// Fetch all users
self.ref?.child("Users").observe(DataEventType.childAdded, with: { (snapshot) in
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) //This print is empty
completion("FetchAllUsers")
}
}
arrays swift firebase firebase-realtime-database
edited Nov 16 '18 at 5:34
PradyumanDixit
2,1872820
asked Nov 15 '18 at 18:43
olleolle
4929
I am appending user info from Firebase into an array but it seems like the array(usersArray) is empty in all prints after the loop. The array is declared outside the function. Any ideas why? Thank you.
func fetchAllUsers(completion: @escaping (_ message: String) -> Void){
//User or advertiser?
let uid = Auth.auth().currentUser?.uid
Database.database().reference(withPath: "Advertiser").child(uid!).observeSingleEvent(of: .value, with: { (snapshot) in
if snapshot.exists(){
myAdvertiserVar.advertiser = true
// Fetch all users
self.ref?.child("Users").observe(DataEventType.childAdded, with: { (snapshot) in
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) //This print is empty
completion("FetchAllUsers")
}
}
arrays swift firebase firebase-realtime-database
arrays swift firebase firebase-realtime-database
edited Nov 16 '18 at 5:34
PradyumanDixit
2,1872820
asked Nov 15 '18 at 18:43
olleolle
4929
edited Nov 16 '18 at 5:34
PradyumanDixit
2,1872820
asked Nov 15 '18 at 18:43
olleolle
4929
edited Nov 16 '18 at 5:34
PradyumanDixit
2,1872820
edited Nov 16 '18 at 5:34
PradyumanDixit
2,1872820
edited Nov 16 '18 at 5:34
PradyumanDixit
2,1872820
2,1872820
asked Nov 15 '18 at 18:43
olleolle
4929
asked Nov 15 '18 at 18:43
olleolle
4929
asked Nov 15 '18 at 18:43
olleolle
4929
4929
stackoverflow.com/a/44490781/5009432. Reference this -- your difference and this is that you need to add the completion INSIDE your observe function, whereas it will know when it is done. Yours does not.
– impression7vx
Nov 15 '18 at 19:00
This did not solve it for me, It only produces prints until the looping has ended. Not only one single print and one completion message as i wish for. Do you know why?
– olle
Nov 15 '18 at 19:28
Yea, one sec. Gonna add answer.
– impression7vx
Nov 15 '18 at 19:31
stackoverflow.com/a/42615219/5009432. Here, this shows you how to determine when Firebase is done calling. You can't do it your way as you are . observing through each child, and you never know which 1 is the last.
– impression7vx
Nov 15 '18 at 19:41
1
You are missing the concept of "asynchronism". If you addprint("will append")just beforeself.usersArray.append(user), andprint("will call completion")just beforecompletion("FetchAllUsers")you'll see that the order of the output is not the one you think of...
– Larme
Nov 15 '18 at 19:48
|
show 3 more comments
stackoverflow.com/a/44490781/5009432. Reference this -- your difference and this is that you need to add the completion INSIDE your observe function, whereas it will know when it is done. Yours does not.
– impression7vx
Nov 15 '18 at 19:00
This did not solve it for me, It only produces prints until the looping has ended. Not only one single print and one completion message as i wish for. Do you know why?
– olle
Nov 15 '18 at 19:28
Yea, one sec. Gonna add answer.
– impression7vx
Nov 15 '18 at 19:31
stackoverflow.com/a/42615219/5009432. Here, this shows you how to determine when Firebase is done calling. You can't do it your way as you are . observing through each child, and you never know which 1 is the last.
– impression7vx
Nov 15 '18 at 19:41
1
You are missing the concept of "asynchronism". If you addprint("will append")just beforeself.usersArray.append(user), andprint("will call completion")just beforecompletion("FetchAllUsers")you'll see that the order of the output is not the one you think of...
– Larme
Nov 15 '18 at 19:48
stackoverflow.com/a/44490781/5009432. Reference this -- your difference and this is that you need to add the completion INSIDE your observe function, whereas it will know when it is done. Yours does not.
– impression7vx
Nov 15 '18 at 19:00
stackoverflow.com/a/44490781/5009432. Reference this -- your difference and this is that you need to add the completion INSIDE your observe function, whereas it will know when it is done. Yours does not.
– impression7vx
Nov 15 '18 at 19:00
This did not solve it for me, It only produces prints until the looping has ended. Not only one single print and one completion message as i wish for. Do you know why?
– olle
Nov 15 '18 at 19:28
This did not solve it for me, It only produces prints until the looping has ended. Not only one single print and one completion message as i wish for. Do you know why?
– olle
Nov 15 '18 at 19:28
Yea, one sec. Gonna add answer.
– impression7vx
Nov 15 '18 at 19:31
Yea, one sec. Gonna add answer.
– impression7vx
Nov 15 '18 at 19:31
stackoverflow.com/a/42615219/5009432. Here, this shows you how to determine when Firebase is done calling. You can't do it your way as you are . observing through each child, and you never know which 1 is the last.
– impression7vx
Nov 15 '18 at 19:41
stackoverflow.com/a/42615219/5009432. Here, this shows you how to determine when Firebase is done calling. You can't do it your way as you are . observing through each child, and you never know which 1 is the last.
– impression7vx
Nov 15 '18 at 19:41
1
1
You are missing the concept of "asynchronism". If you add
print("will append") just before self.usersArray.append(user), and print("will call completion") just before completion("FetchAllUsers") you'll see that the order of the output is not the one you think of...– Larme
Nov 15 '18 at 19:48
You are missing the concept of "asynchronism". If you add
print("will append") just before self.usersArray.append(user), and print("will call completion") just before completion("FetchAllUsers") you'll see that the order of the output is not the one you think of...– Larme
Nov 15 '18 at 19:48
|
show 3 more comments
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stackoverflow.com/a/44490781/5009432. Reference this -- your difference and this is that you need to add the completion INSIDE your observe function, whereas it will know when it is done. Yours does not.
– impression7vx
Nov 15 '18 at 19:00
This did not solve it for me, It only produces prints until the looping has ended. Not only one single print and one completion message as i wish for. Do you know why?
– olle
Nov 15 '18 at 19:28
Yea, one sec. Gonna add answer.
– impression7vx
Nov 15 '18 at 19:31
stackoverflow.com/a/42615219/5009432. Here, this shows you how to determine when Firebase is done calling. You can't do it your way as you are . observing through each child, and you never know which 1 is the last.
– impression7vx
Nov 15 '18 at 19:41
1
You are missing the concept of "asynchronism". If you add
print("will append")just beforeself.usersArray.append(user), andprint("will call completion")just beforecompletion("FetchAllUsers")you'll see that the order of the output is not the one you think of...– Larme
Nov 15 '18 at 19:48