So I found this code to query your database while the user is still typing, but the code was outdated and I've been updating it, but there's an error that I don't know how to fix.
func findFriends(text: String) -> Void {
let ref = Database.database().reference()
ref.child("users").queryOrdered(byChild: "username").queryStarting(atValue: text).queryEnding(atValue: text+"\u{f8ff}").observe(.value, with: { snapshot in
let user = User()
let userArray = [User]()
for u in snapshot.children{
user.name = u.value!["name"] as? String
}
})
I get an error in the last line and it says:
Value of type 'Any' has no member 'value'
The elements in snapshot.children are of type Any, which doesn't have a value property. To get at the value property you need to cast u to a DataSnapshot:
for userSnapshot in snapshot.children{
let userSnapshot = userSnapshot as! DataSnapshot
guard let dictionary = userSnapshot.value as? [String: Any] else { return }
user.name = dictionary["name"] as? String
}
Alternatively, you put the cast in the loop:
for userSnapshot in in snapshot.children.allObjects as? [DataSnapshot] ?? [] {
guard let dictionary = userSnapshot.value as? [String: Any] else { return }
user.name = dictionary["name"] as? String
}
Related
I don't know why cant find how get friends Ids.
her is my code:
func fetchUsers() {
let ref = Firebase.Database.database().reference()
guard let userId = Auth.auth().currentUser?.uid else { return }
let userID = userId
ref.child("Users").child(userID).observe(.childAdded) { (snapshot) in
print("snapshot...\(snapshot)")
let user = User()
if let dictionary = snapshot.value as? [String:AnyObject]{
user.currentUserFriends = dictionary["Friends"] as? String
print("dictionary...\(user.currentUserFriends ?? "no value")")
}
}
}
and my tree from firebase is Users-Uid-Friends-friendID-true.
Solved!
ref.child("Users").child(userID!).child("Friends").observeSingleEvent(of: .value) { (snapshot) in
print("snapshot...\(snapshot)")
let dic = snapshot.value as! NSDictionary
for (key,value) in dic{
let friendsID = key
let friendBool = value
print("key is \(friendsID) and value is \(friendBool)")
let user = User()
user.currentUserFriends = key as? String
}
}
I have stored the comments under a post in firebase realtime database. The problem i have is that when i try to parse out the data from firebase i get an error that says Unexpectedly found nil while unwrapping an Optional value. So for example if i try to pront the data stored under degree, i get this nil error. But when i print "comments" instead of the "degree" i successfully fetch the data. My database structure looks like this.
func obeserveComments() {
// get auto-id of post
let commentKey = self.keyFound
let postRef = Database.database().reference().child("posts").child(commentKey)
var tempComments = [Comments]()
postRef.observe(.value, with: {(snapshot) in
if let dict = snapshot.value as? [String:Any] {
if let comments = dict["comments"] as? [String:Any] {
let degree = comments["reply degree"] as! String
// let name = comments["reply name"] as! String
// let text = comments["reply text"] as! String
// let university = comments["reply university"] as! String
// let photoURL = comments["reply url"] as! String
// let url = URL(string: photoURL)
// let timestamp = comments["timestamp"] as! Double
print(degree)
}
}
})
}
The answer by #aytroncb is a good answer, I prefer to leave Firebase data 'Firebasy' as long as possible. In other words coverting to dictionaries looses ordering and and find code like this
[String: [String: [String: Any]]]
To be very hard to read.
I prefer
let snap = snapshot.childSnapshot("comments") //snap becomes a DataSnapshot
So my solution maintains the order and leverages .childSnapshot to leave data in it's DataSnapshot form.
func readPostComments() {
let postRef = self.ref.child("posts") //self.ref points to my firebase
postRef.observeSingleEvent(of: .value, with: { snapshot in
let allPosts = snapshot.children.allObjects as! [DataSnapshot]
for postSnap in allPosts {
print("postId: \(postSnap.key)")
let commentsSnap = postSnap.childSnapshot(forPath: "comments") //will be a DataSnapshot
let allComments = commentsSnap.children.allObjects as! [DataSnapshot]
for commentSnap in allComments {
print(" commentId: \(commentSnap.key)")
let replyDegree = commentSnap.childSnapshot(forPath: "reply_degree").value as? String ?? "No Degree"
let replyName = commentSnap.childSnapshot(forPath: "reply_name").value as? String ?? "No Name"
print(" degree: \(replyDegree) by: \(replyName)")
}
}
})
}
EDIT
For a single post, remove the top part of the code that reads in and iterates over all posts.
func readCommentsForOnePost() {
let postRef = self.ref.child("posts")
let postCommentRef = postRef.child("post_0")
postCommentRef.observeSingleEvent(of: .value, with: { snapshot in
print("postId: \(snapshot.key)")
let commentsSnap = snapshot.childSnapshot(forPath: "comments") //will be a DataSnapshot
let allComments = commentsSnap.children.allObjects as! [DataSnapshot]
for commentSnap in allComments {
print(" commentId: \(commentSnap.key)")
let replyDegree = commentSnap.childSnapshot(forPath: "reply_degree").value as? String ?? "No Degree"
let replyName = commentSnap.childSnapshot(forPath: "reply_name").value as? String ?? "No Name"
print(" degree: \(replyDegree) by: \(replyName)")
}
})
}
Its because firebase is returning your data like this
{
"MAKFW244kdL)Cw;1": [Array of data],
"LOPSw!35pa3flAL4": [Array of data],
"ALV34VR4_A6Vn1a": [Array of data]
}
So change your initial casting of snapshot.value to this:
if let dict = snapshot.value as? [String: [String: Any]]
then loop through that new dictionary like this:
for objectJson in dict.values {
if let comments = objectJson["comments"] as? [String: [String: Any]] {
for commentJson in comments.values {
let degree = commentJson["reply_degree"] as? String
}
}
}
Update
Just read through your post again and noticed your trying to access the comments directly with a key, your first going to need to provide the PostId. Then you can use the above code to loop through the objects
let postRef = Database.database().reference().child("posts").child(postID)
alternatively I believe you can have the comments returned as a normal list by doing something like this:
let postRef = Database.database().reference().child("posts").child("\(postID)/{id}")
I want to get list of users from Firebase database and put that in a Users array but I am unable to get data from the snapshot
This is what I have tried
class User: NSObject {
var name: String?
var email: String?
}
var users : [User] = []
func fetchUsers() {
Database.database().reference().child("users").observe(.childAdded) { (snapshot) in
for child in (snapshot.children) {
let snap = child as! DataSnapshot
let dic = snap.value as! [String: String] // erros here
//print((dic["name"]))
//WANT TO LOAD THE LIST OF USERS INTO `var users`
}
}
}
Error
Could not cast value of type '__NSCFString' to 'NSDictionary'
This is how my data looks like on firebase database
Thanks for your help
R
That's because DataSnapshot is a String to Object dictionary. This should do the trick
guard let dict = child.value as? [String : AnyObject]
else {
print("couldn't cast to dictionary")
return
}
print("successfully cast to dictionary")
print(dict["name"])
print(dict["email"])
func fetchUsers() {
Database.database().reference().child("users").observe(.childAdded) { (snapshot) in
for child in snapshot.children.allObjects as! [DataSnapshot] {
print(child.value)
if let dict = child.value as? [String : AnyObject] {
if let email = dict["email"] {
print(email)
}
}
}
}
}
Hi there i'm newest in swift. I am working with a firebase database with at 2 layer of hierarchy as well as many children for each node. I got 1st layer (descript, enddata and other), but i stll can't get the news node. Is in 3 to 5 random keys. I sow many issues but still not have issue for me.
I'm understand i'm doing some wrong but what?
The Firebase is:
i need retreat the news child
struct is
struct ICONews {
let ICOId: String
let news1: String
let news2: String
let news3: String
init?(ICOId: String, dict: [String: Any] ) {
self.ICOId=ICOId
guard let news1 = dict[""] as? String,
let news2 = dict[""] as? String,
let news3 = dict[""] as? String
else { return nil }
self.news1 = news1
self.news2 = news2
self.news3 = news3
}
}
struct NewsSnapShot {
let posts: [ICONews]
init?(with snapshot: DataSnapshot) {
var posts = [ICONews] ()
guard let snapDict = snapshot.value as? [String: [String: Any]] else { return nil }
for snap in snapDict {
guard let post = ICONews (ICOId: snap.key, dict: snap.value) else {continue}
posts.append(post)
}
self.posts=posts
}
}
class of DataBase
class DatabaseService {
static let shared = DatabaseService()
private init(){}
let ICOReference = Database.database().reference()
}
and retreat method
DatabaseService.shared.ICOReference.child("news").observe(DataEventType.value, with: { (snapshot) in
guard let postsSnapShot = ICOSnapShot(with: snapshot) else {return}
})
done
Database.database().reference().observeSingleEvent(of: .value, with: {(snapshot) in
let enumerator = snapshot.children
while let rest = enumerator.nextObject() as? DataSnapshot {
let values = (rest as! DataSnapshot).value as? NSDictionary
let enumeratorMap1 = (rest as! DataSnapshot).children
while let rest2 = enumeratorMap1.nextObject() as? DataSnapshot {
let valuesMap1 = (rest2 as! DataSnapshot).value as? NSDictionary
if (rest2 as! DataSnapshot).key == "news" {
print(rest2.value)
}
}
}
})
Make the the Firebase Api call like
Database.database().reference().child("users").child(userID).observe(.childAdded, with: { (snapshot) in
if snapshot.exists() {
let receivedMessage = snapshot.value as! [String: Any]
let name = receivedMessage["name"] as? String ?? ""
let id = receivedMessage["id"] as? Double ?? 0.0
let profileurl = receivedMessage["url"] as? String ?? ""
completion(User(name: name, id: id, url: url))
} else {
failure()
}
})
I am using the subscript in the following code incorrectly for this Firebase data pull, but I can't figure out what I am doing wrong. I get an error of Ambiguous use of subscript for the let uniqueID = each.value["Unique ID Event Number"] as! Int line.
// Log user in
if let user = FIRAuth.auth()?.currentUser {
let uid = user.uid
// values for vars sevenDaysAgo and oneDayAgo set here
...
let historyRef = self.ref.child("historyForFeedbackLoop/\(uid)")
historyRef.queryOrdered(byChild: "Unix Date").queryStarting(atValue: sevenDaysAgo).queryEnding(atValue: oneDayAgo).observeSingleEvent(of: .value, with: { snapshot in
if (snapshot.value is NSNull) {
print("user data not found")
}
else {
if let snapDict = snapshot.value as? [String:AnyObject] {
for each in snapDict {
// Save the IDs to array.
let uniqueID = each.value["Unique ID Event Number"] as! Int
self.arrayOfUserSearchHistoryIDs.append(uniqueID)
}
}
else{
print("SnapDict is null")
}
}
})
}
I tried to applying what I learned from this post, but I couldn't figure out what I am missing because I thought I was letting the compiler know what type of dictionary it is with the "as? [String:AnyObject]"
Any thoughts or ideas would be greatly appreciated!
My preferred way of dealing with data is to unwrap the FIRDataSnapshot as late as possible.
ref!.observe(.value, with: { (snapshot) in
for child in snapshot.children {
let msg = child as! FIRDataSnapshot
print("\(msg.key): \(msg.value!)")
let val = msg.value! as! [String:Any]
print("\(val["name"]!): \(val["message"]!)")
}
})
Taking Frank's feedback into account, here is the actual working code I used that follows that approach in case it's helpful.
// Log user in
if let user = FIRAuth.auth()?.currentUser {
let uid = user.uid
// values for vars sevenDaysAgo and oneDayAgo set here
...
let historyRef = self.ref.child("historyForFeedbackLoop/\(uid)")
historyRef.queryOrdered(byChild: "Unix Date").queryStarting(atValue: sevenDaysAgo).queryEnding(atValue: oneDayAgo).observeSingleEvent(of: .value, with: { snapshot in
if (snapshot.value is NSNull) {
print("user data not found")
}
else {
for child in snapshot.children {
let data = child as! FIRDataSnapshot
let value = data.value! as! [String:Any]
self.arrayOfUserSearchHistoryIDs.append(value["Unique ID Event Number"] as! Int)
}
}
})
}