Accessing Nested NSDictionary values in Swift 3.0

Question

I have the following data I received from Firebase. I have made my snapshotValue a NSDictionary.

self.ref.child("users").child(facebookID_Firebase as! String).observeSingleEvent(of: .value, with: { (snapshot) in
            let snapshotValue = snapshot.value as? NSDictionary
            print(snapshotValue, "snapshotValue")
            //this line of code doesn't work
            //self.pictureURL = snapshot["picture"]["data"]["url"]
        }) { (error) in
            print(error.localizedDescription)
        }

I tried How do I manipulate nested dictionaries in Swift, e.g. JSON data? , How to access deeply nested dictionaries in Swift , and other solutions yet no luck.

How do I access the url value inside the data key AND the picture key?

I can make another reference in Firebase and get the value, but I'm trying to save another request.

BTW when you make another reference Firebase does not send out another request. All those mombo jambo is handled by Firebase client itself. — Cemal Eker, Oct 19 '16 at 00:18
please check this answer https://stackoverflow.com/a/43715807/3806350 — dimohamdy, Jun 01 '17 at 11:46

score 2 · Answer 1 · answered Oct 19 '16 at 00:25

2

When you refrence to a key of a Dictionary in swift you get out an unwrapped value. This means it can be nil. You can force unwrap the value or you can use pretty if let =

this should probably work.

if let pictureUrl = snapshot["picture"]["data"]["url"] {
    self.pictureURL = pictureUrl
}

answered Oct 19 '16 at 00:25

Cemal Eker

1,266
1
9
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Hey sir, unfortunately I got the following: Type 'FIRDataSnapshot' has no subscript members – Rohit Tigga Oct 19 '16 at 00:28
How to proceed? I'm currently looking at: http://stackoverflow.com/questions/39136026/type-any-has-no-subscript-members-firebase – Rohit Tigga Oct 19 '16 at 00:29
It is definately not a Dictionary then. Use `childSnapshotForPath:` method and create a new snapshot. `childSnapshotForPath:"picture.data.url"` – Cemal Eker Oct 19 '16 at 00:31
This doesn't return a value: snapshot.childSnapshot(forPath: "picture.data.url") – Rohit Tigga Oct 19 '16 at 01:06
Any idea how to do this, Cemal? – Rohit Tigga Oct 19 '16 at 02:06

score 1 · Answer 2 · answered Oct 19 '16 at 06:01

1

Try using :-

 if let pictureDict = snapshot.value["picture"] as? [String:AnyObject]{

        if let dataDict = pictureDict.value["data"] as? [String:AnyObject]{

              self.pictureURL =  dataDict.value["url"] as! String

           }
   }

answered Oct 19 '16 at 06:01

Dravidian

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3
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74

score 0 · Answer 3 · answered Dec 08 '17 at 19:59

0

Inline dictionary unwrapping:

let url = ((snapshot.value as? NSDictionary)?["picture"] as? NSDictionary)?["url"] as? String

answered Dec 08 '17 at 19:59

Eugene Brusov

17,146
6
52
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score 0 · Answer 4 · answered Mar 12 '18 at 22:58

You can use the following syntax, that is prettier:

    if let pictureDict = snapshot.value["picture"] as? [String:AnyObject],
        let dataDict = pictureDict.value["data"] as? [String:AnyObject] {
            self.pictureURL =  dataDict.value["url"] as! String
        }
    }

Accessing Nested NSDictionary values in Swift 3.0

4 Answers4

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