Update child values in Firebase with Swift

Question

I am trying to implement updating Firebase database once a user taps on a button. When the user logs in (with Facebook in my case), a data structure is created successfully with the initial values in the data tree created.

What I want to accomplish is once the user is in the app and they create a new item it saves it to the database, hence updates the values under one of the already created child values. See my code and screenshot for reference - thanks for any help!

// user taps button to send item to be updated in Firebase data tree
func confirmAddPlace() {

    // add place to tableview array
    let accessToken = FBSDKAccessToken.current()
    guard let accessTokenString = accessToken?.tokenString else { return }

    let credentials = FIRFacebookAuthProvider.credential(withAccessToken: accessTokenString)
    FIRAuth.auth()?.signIn(with: credentials, completion: { (user, error) in
        if error != nil {
            print("Something went wrong with our FB user: ", error ?? "")
            return
        }

    guard let uid = user?.uid else {
        return
    }
    // here is where i am having issues
    let ref = FIRDatabase.database().reference().root.child("Users").child(uid).child("Places")
    let values = ["place": self.placeNameLabel.text]
    ref.updateChildValues(values)
})

    animateOut()
}

func viewController(_ viewController: GMSAutocompleteViewController, didAutocompleteWith place: GMSPlace) {
        let placeID = place.placeID
        placesClient.lookUpPlaceID(placeID, callback: { (place, error) -> Void in
            if let error = error {
                print("lookup place id query error: \(error.localizedDescription)")
                return
            }
            guard let place = place else {
                return
            }
        })
        let selectedPlace = place.formattedAddress
        if let name = selectedPlace as String!
        {
            self.placeNameLabel.text = "Are you sure you would like to add \(name) to your places?"
        }
    }

Solution

You want to change the value of Places, which is the value in the child of child(uid).

let values = ["place": self.placeNameLabel.text]
let ref = FIRDatabase.database().reference().root.child("users").child(uid).updateChildValues(["Places": values])