Firebase在要求有更多孩子的孩子时获得错误的快照？

Question

I am having trouble grabbing my data from Firebase. I have setup three test data sets, each item is called a "Campaign". For every "Campaign" there can be a user that has completed the campaign which will follow under the campaign id -> users -> userid -> confirmImageUrl and the image that has been completed. When I try to pull the users child and the child of the users, I am not getting all the data. When there are no users, it is pulling it correclty.

In Firebase this is how it is setup: Firebase Data Setup

In my viewDidLoad , this is how I am pulling the data. Each "campaign" goes into a UITableViewCell :

DataService.ds.DATABASE_BASE_CAMPAIGNS.observe(.value, with: { (snapshot) in
    print("menan check:\(snapshot.value!)")
    if let snapshot = snapshot.children.allObjects as? [FIRDataSnapshot] {
        print("menan check: \(snapshot)")
        self.campaigns = []
        for snap in snapshot {
            if let campaignData = snap.value as? Dictionary <String, AnyObject> {
                let key = snap.key
                let campaign = Campaigns(campaignKey: key, campaignData: campaignData)
                print("menan check: \(campaignData)")
                self.campaigns.append(campaign)
            }
        }
    }
    self.tableView.reloadData()
})

This is the output: The Output from the snapshot received

I have spent quite a long time trying to figure it out? Anyone know whats wrong?

Answer 1

Your data is pretty deep so you will need a couple more Dictionaries to work with the key value pairs.

Here's a quick solution to get to the deepest piece of data, the confirm value. It could be shortened but I left it verbose so it could be explained line by line.

    campaignRef.observe(.value, with: { (snapshot) in
            for snap in snapshot.children { //iterate over 21hb, 989 huv etc

                //contains all data in 21hb
                let node = snap as! FIRDataSnapshot

                // represent the data in the node as a dictionary
                let nodeDict = node.value as! [String: AnyObject]

                //grab just the users node, whose value is also a dictionary
                let users = nodeDict["users"] as! [String: AnyObject]

                //iterate over each user in the users node
                for user in users {
                    let userId = user.key //this is the user id

                    //the value is a dictionary of key: value
                    // as in   confirm: url
                    let value = user.value as! [String: AnyObject]

                    //get the value for the confirm key, which is the url
                    let confirm = value["confirm"]

                    //print the user it and the confirm url
                    print("key = \(userId)  value = \(confirm!)")
                }
            }
    })