Firebase: Access a snapshots children using swift3 - ios

I'm trying to get the value of multiple children of my snapshot in order to append my cellDataArray by name and speed.
My code is working for name, but not for speed..
ref = FIRDatabase.database().reference().child("BasicInfo")
let query = ref?.queryOrdered(byChild: "Operator")
query?.observeSingleEvent(of: .value, with: { (snapshot) in
for child in snapshot.children.allObjects as! [FIRDataSnapshot] {
let name = child.key
let speed = child.childSnapshot(forPath: "Speed")
self.cellDataArray.append(cellData(mainText: name, Speed: ""))
self.tableView.reloadData()
}
})
This is my Firebase structure:

Try to access the value property of FIRDataSnapshot to get the Speed.
for child in snapshot.children.allObjects as! [FIRDataSnapshot] {
let name = child.key
if let dic = child.value as? [String:Any], let speed = dic["Speed"] as? Int
let operator = dic["Operator"] as? String {
print(operator)
self.cellDataArray.append(cellData(mainText: name, Speed: "\(speed)"))
}
}
DispatchQueue.main.async {
self.tableView.reloadData()
}

Related

How do I get from Firebase database the most recent data in swift?

I am storing data in my firebase database but when I want to retrieve the differents name of my users, unlike my profile image who is retrieving from most recent, the names are retrieving in alphabetical orders... here's my code :
func getNamesUser(){
let rootRef = Database.database().reference()
let query = rootRef.child("users").queryOrdered(byChild: "name")
query.observeSingleEvent(of: .value) { (snapshot) in
let nameArray = snapshot.children.allObjects as! [DataSnapshot]
for child in nameArray{
let value = child.value as? NSDictionary
let child = value?["name"] as? String
self.arrayName.append(child!)
}
self.collectionView.reloadData()
}
}
func getImgUser(){
let rootRef = Database.database().reference()
let query = rootRef.child("users").queryOrdered(byChild: "profileImgURL")
query.observeSingleEvent(of: .value) { (snapshot) in
let nameArray = snapshot.children.allObjects as! [DataSnapshot]
for child in nameArray{
let value = child.value as? NSDictionary
let child = value?["profileImgURL"] as? String
self.arrayProfilImage.append(child!)
}
self.collectionView.reloadData()
}
}
and here's my firebase database tree :

iOS Firebase asynchronous data retrieval into Array

I try to retrieve data from Firebase into Array. Because it runs asynchronously, the results that I want to show in my CollectionView is a delay until I switch back and forth. I am very new to asynchronous functions in iOS. Please help me to complete my code.
ref = Database.database().reference(withPath: "MyTest/Video")
ref?.observeSingleEvent(of: .value, with: { snapshot in
if !snapshot.exists() { return }
if let result = snapshot.children.allObjects as? [DataSnapshot] {
for child in result {
let autoID = child.key as String //get autoID
let title = snapshot.childSnapshot(forPath: "\(autoID)/Title").value
let url = snapshot.childSnapshot(forPath: "\(autoID)/URL").value
let views = snapshot.childSnapshot(forPath: "\(autoID)/Views").value
self.arrayAllTitle.append(title as! String)
self.arrayAllId.append(url as! String)
self.arrayAllDesc.append(views as! String)
}
}
})
You need to reload the collection after you retrieve the data so after the for loop call reloadData()
for child in result {
}
self.collectionView.reloadData()
//
func getValueFromDatabase(completion: #escaping (_ status: Bool) -> Void){
ref = Database.database().reference(withPath: "MyTest/Video")
ref?.observeSingleEvent(of: .value, with: { snapshot in
if !snapshot.exists() { return }
if let result = snapshot.children.allObjects as? [DataSnapshot] {
for child in result {
let autoID = child.key as String //get autoID
let title = snapshot.childSnapshot(forPath: "\(autoID)/Title").value
let url = snapshot.childSnapshot(forPath: "\(autoID)/URL").value
let views = snapshot.childSnapshot(forPath: "\(autoID)/Views").value
self.arrayAllTitle.append(title as! String)
self.arrayAllId.append(url as! String)
self.arrayAllDesc.append(views as! String)
}
completion(true)
}
else {
completion(false)
}
})
}
//
self.getValueFromDatabase { (status) in
if status {
// success
}
}
I'm working with Firebase in my project right now. I would suggest the following solution: wrap the database observer in a distinct function which gets completion block as a parameter.
func getValueFromDatabase(completion: ()->Void){
ref = Database.database().reference(withPath: "MyTest/Video")
ref?.observeSingleEvent(of: .value, with: { snapshot in
if !snapshot.exists() { return }
if let result = snapshot.children.allObjects as? [DataSnapshot] {
for child in result {
let autoID = child.key as String //get autoID
let title = snapshot.childSnapshot(forPath: "\(autoID)/Title").value
let url = snapshot.childSnapshot(forPath: "\(autoID)/URL").value
let views = snapshot.childSnapshot(forPath: "\(autoID)/Views").value
self.arrayAllTitle.append(title as! String)
self.arrayAllId.append(url as! String)
self.arrayAllDesc.append(views as! String)
}
completion()
}
})
}
This way you can call the function from anywhere providing the desired action after fetching data from db is finished:
getValueFromDatabase(completion:{
self.collectionView.reloadData() //or any other action you want to fulfil
})

How can I retrieve data from many child in firebase database

I was trying to retrieve data from firebase. I can retrieve data from a single child. But how can I retrieve data from many child?
I tried this way
func fatchSchdual(){
ref.child("Products").child(productdetailes[myIndex].userId!).child("Schedule").child("0").observeSingleEvent(of: .value) { (snapshot) in
if snapshot.childrenCount > 0{
for Schdu in snapshot.children.allObjects as! [DataSnapshot]{
let schdual = Schdu.value as? [String: AnyObject]
let startTime = schdual?["start"]
let endTime = schdual?["end"]
if let StartTime = startTime{
self.publishTime.text = StartTime as? String
}
}
}
}
}
but I didn't get any data.
func fatchFacilities(){
ref.child("Products").child(productdetailes[myIndex].userId!).child("Facility").observeSingleEvent(of: .value) { snapshot in
for child in snapshot.children {
if let value = (child as! DataSnapshot).value as? [String : Any] {
let name = value["name"] as? String
let unit = value["unit"] as? String
let facility = Facility(name: name, unit: unit)
facilities.append(facility)
}
}
}
}

swift 3 firebase snapshot if value equal to ... fetch

I'm Trying to check if the rooms's value 'Owner' equals to the current user id if so then fetch all data including the key value and continue checking other children of 'rooms'
I was trying, but I fail finding the solution though it might seem easy so please help me with your suggestions or ideas. My code so far :
Database.database().reference().child("rooms").queryOrdered(byChild: "Owner").observeSingleEvent(of: .value, with: { (snapshot) in
let currentUser = Auth.auth().currentUser?.uid
if !snapshot.exists() {
print("No data found")
return
}
var rooms = snapshot.value as! [String:AnyObject]
let roomKeys = Array(rooms.keys)
for roomKey in roomKeys {
guard
let value = rooms[roomKey] as? [String:AnyObject]
else
{
continue
}
let title = value["title"] as? String
let description = value["description"] as? String
let roomPictureUrl = value["Room Picture"] as? String
let longitude = value["Longtitude"] as? String
let latitude = value["Latitude"] as? String
let dateFrom = value["Date From"] as? String
let dateTo = value["Date To"] as? String
let owner = value["Owner"] as? String
let myRooms = Room(roomID: roomKey,title: title!, description: description!, roomPicutreURL: roomPictureUrl!, longitude: longitude!, latitude: latitude!, dateFrom: dateFrom!, dateTo: dateTo!, owner: owner!)
self.rooms.append(myRooms)
self.tableView.reloadData()
print(snapshot.value)
}
})
You're missing the value in your query:
Database.database().reference()
.child("rooms")
.queryOrdered(byChild: "Owner")
.queryEqual(toValue: "STbz...")
.observeSingleEvent(of: .value, with: { (snapshot) in
See for this and more query operators, the documentation on filtering data.
Mark:- Swift 5
Database.database().reference().child("user")
.queryOrdered(byChild: "UserPhoneNumber") //in which column you want to find
.queryEqual(toValue: "Your phone number or any column value")
.observeSingleEvent(of: .value, with: { (snapshot) in
if snapshot.childrenCount > 0
{
if let snapShot = snapshot.children.allObjects as? [DataSnapshot] {
//MARK:- User Exist in database
for snap in snapShot{
//MARK:- User auto id for exist user
print(snap.key)
break
}
}
}
else if snapshot.childrenCount == 0
{
//MARK:- User not exist no data found
}
})

Firebase Multi Level Database into tableview

How do I get data from a child deeper into a database that has an unknown name?
My example structure is below.
This code works (to get the snapshot data) but I am hardcoding the second child. I will not always know this value (Bus 1).
let ref = FIRDatabase.database().reference()
let usersRef = ref.child("Trips").child("Bus 1")
usersRef.observeSingleEvent(of: .value, with: { (snapshot) in
for snap in snapshot.children {
let userSnap = snap as! FIRDataSnapshot
let uid = userSnap.key //the uid of each user
let userDict = userSnap.value as! [String:AnyObject] //child data
let personOn = userDict["getOn"] as! String
print("key = \(uid) is at getOn = \(personOn)")
}
})
This will print:
key = Stop 1 is at getOn = 3
key = Stop 2 is at getOn = 7
Should I be structuring this differently? Flatter?
Thanks and let me know of any questions.
This is a more preferable way as I have a class for TripDetails which goes into an array to load into the table. But again, I do not know what the second child's name is.
FIRDatabase.database().reference().child("Trips").child("Bus 1").observe(.childAdded, with: { (snapshot) in
if let dictionary = snapshot.value as? [String: AnyObject] {
let trip = TripDetails()
trip.setValuesForKeys(dictionary)
self.trips.append(trip)
DispatchQueue.main.async {
self.tableView.reloadData()
}
}
print(snapshot)
}, withCancel: nil)
I'm still not super sure what data you want exactly. If all you want is all the data you can just do this.
let ref = FIRDatabase.database().reference().child("Trips")
ref.observeSingleEvent(of: .value, with: { snapshot in
let enumerator = snapshot.children
while let bus = enumerator.nextObject() as? FIRDataSnapshot {
print("\(bus.key)")
let enumerator = bus.children
while let stop = enumerator.nextObject() as? FIRDataSnapshot {
let stopDict = stop.value as? [String: Any]
let uid = stop.key
let personOn = stopDict?["getOn"] as? String
print("key = \(uid) is at getOn = \(personOn)")
}
}
})

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