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Jutyar Nerway
Jutyar Nerway
1,242 Points

Reading location from multiple users with unique ID using Swift 4 and Firebase


so I've been struggling with this one for a two days now. I've searched everywhere and haven't really found an answer that could help me. Maybe I'm using the wrong keywords.

Here is the issue.

I have this data in my Firebase Realtime Database

-users VZUFNaLJ6YN5aqIDaFGmxWKGYNc2 -location -latitude: 123 -longitude: 123 RXUFNaLJ6OI7G57DaFGmxWKHG76T -location -latitude: 321 -longitude: 321 And the output I'm hoping to get is this

latitude: 123

longitude: 123

latitude: 321

longitude: 321

I really don't have a working code to post here, I was hoping if someone could help me understand what needs to be done. Thank you.

What I have so far is this

// Read location from all user func globalCoor(){ ref.child("location").observeSingleEvent(of: .value) { (snapshot) in let locationData = snapshot.value as? [String: Any] print(locationData) } }

1 Answer

So you are just trying to get the data out of Firebase correct?

You need to model your data with a couple of structs first. Judging by your data it will be as [String: [String: Any]].

Keep in mind I haven't ran this code but this should get you going:

struct User {
    userID: String
    longitude: Int
    latitude: Int

    // Initialize below. You will most likely have to convert string to Int
    init?(userKey: String, dict: [String: Any]) {
        let userID = userKey

        guard let longitude = dict["longitude"] as? Int,
                  let latitude = dict["latitude"] as? Int 

        self.userID = userID
        self.longitude = longitude
        self.latitude = latitude


Next you will need a user snapshot struct which will have a object 'users' which is an array of 'User'.

struct userSnapshot {

    let users: [User]

    init?(with snapshot: DataSnapshot) {
        var users = [User]()
        guard let snapDict = snapshot.value as? [String: [String: Any]] else { return nil }
        for snap in snapDict {
            guard let user = User(userKey: snap.key, dict: snap.value) else { continue }
        self.users = users

So now the data will be modeled into one object which is an array of 'User' and the next object will be the individual user so everything is separate. I think this is what you are trying to accomplish.

Now when you get your data from Firebase it will be something like this.

// Instead of this
locationData = snapshot.value as? [String: Any] print(locationData) } }

// Do this
guard let userSnapshot = userSnapshot(with: snapshot) else { return }

Also it is better to keep data about the user in the user node of your database such as name etc and then have a separate node which is location. Research relational database. You want to keep it shallow and not nested as much as possible.

        -firstName: John
        -lastName: Doe
        -email: some email
        -longitude: 123
        -latitude: 123

Also make sure to check the markdown sheet so your code is readable when you post. It should look like this:

   // Code goes here. 
```  // Also make sure to end your code with 3 more back ticks.

Did this help you out?