ios - Firebase Database indexPath -

i'm trying retrieve data firebase using function i'm not getting data:

 func retrievevideos(_ completionblock: @escaping (_ success: bool, _ error: error?) -> ()) {     let usermessagesref = dataservice.instance.ref_artistarts.child(auth.auth().currentuser!.uid)      usermessagesref.observe(.childadded, with: { [weak self] (snapshot) in          if let snapshot = snapshot.children.allobjects as? [datasnapshot] { 

print("snapshot: (snapshot.count)") = 12

        }         guard let strongself = self else {return}          guard let dictionary = snapshot.value as? [string: anyobject] else {             completionblock(false, nil)             return         }         var arts = [art?]()         if let art = artviewmodelcontroller.parse(dictionary) {             arts.append(art) 

            print(arts.count) = 1 

        }         strongself.viewmodels = artviewmodelcontroller.initviewmodels(arts)         completionblock(true, nil)      }) { (error: error) in         completionblock(false, error)     } }    var viewmodelscount: int {     return viewmodels.count }   func viewmodel(at index: int) -> artviewmodel? {     guard index <= 0 && index < viewmodelscount else { return nil }     return viewmodels[index] } 

}

private extension artviewmodelcontroller {  static func parse(_ dictionary: [string: any]) -> art? {     let artid = dictionary["artid"] as? string ?? ""     let imgurl = dictionary["imageurl"] as? string ?? ""     let title = dictionary["title"] as? string ?? ""     let description = dictionary["description"] as? string ?? ""     let price = dictionary["price"] as? nsnumber ?? 0     let type = dictionary["type"] as? string ?? ""     let height = dictionary["height"] as? nsnumber ?? 0     let width = dictionary["width"] as? nsnumber ?? 0     let postdate = dictionary["postdate"] as? nsnumber ?? 0     return art(artid: artid, imgurl: imgurl, price: price, title: title, description: description, type: type, height: height, width: width, postdate: postdate) }   static func initviewmodels(_ arts: [art?]) -> [artviewmodel?] {     print("second video count: \(arts.count)")     return arts.map { art in         if let art = art {             return artviewmodel(art: art)         } else {             return nil         }     } } 

}

my problem index.count equal 1 it's supposed equal 12.

here's original code:

 func retrieveusers(_ completionblock: @escaping (_ success: bool, _ error: nserror?) -> ()) {     let urlstring = "http://localhost:3000/users"     let session = urlsession.shared      guard let url = url(string: urlstring) else {         completionblock(false, nil)         return     }     let task = session.datatask(with: url) { [weak self] (data, response, error) in         guard let strongself = self else { return }         guard let data = data else {             completionblock(false, error nserror?)             return         }         let error = nserror.createerror(0, description: "json parsing error")         if let jsondata = try? jsonserialization.jsonobject(with: data, options: .allowfragments) as? [[string: anyobject]] {             guard let jsondata = jsondata else {                 completionblock(false,  error)                 return             }             var users = [user?]()             json in jsondata {                 if let user = userviewmodelcontroller.parse(json) {                     users.append(user)                 }             }              strongself.viewmodels = userviewmodelcontroller.initviewmodels(users)             completionblock(true, nil)         } else {             completionblock(false, error)         }     }     task.resume() } 

so i'm trying same thing firebase. if need more details please ask!

snapshot print:

    snapshot: optional({     description = "yes ";     height = 87;     imageurl = "https://firebasestorage.googleapis.com/v0/b/medici-b6f69.appspot.com/o/art%2f4bjurh5ffnoub2d4ohgfrqem7il2%2fb6e2a9f0-c409-4732-b6d9-14382e6796f5?alt=media&token=32992b9c-4a08-456d-8950-119f681b4cdc";     postdate = 1498921599547;     price = 23;     private = 0;     title = "yes ";     type = modern;     useruid = 4bjurh5ffnoub2d4ohgfrqem7il2;     width = 71; }) snapshot: optional({     artheight = 85;     artwidth = 123;     description = "yes ";     height = 85;     imageurl = "https://firebasestorage.googleapis.com/v0/b/medici-b6f69.appspot.com/o/art%2f4bjurh5ffnoub2d4ohgfrqem7il2%2f16280189-5aea-47cb-9251-c95635ffe56c?alt=media&token=8198df4e-da8c-4883-b278-fc7c14730f69";     postdate = 1498921623601;     price = 23;     private = 0;     title = "blacks don\u2019t crack ";     type = abstract;     useruid = 4bjurh5ffnoub2d4ohgfrqem7il2;     width = 123; }) snapshot: optional({     artheight = 81;     artwidth = 11;     description = "yes ";     height = 81;     imageurl = "https://firebasestorage.googleapis.com/v0/b/medici-b6f69.appspot.com/o/art%2f4bjurh5ffnoub2d4ohgfrqem7il2%2f305fde5c-1c5c-4abd-b4a1-4fa224421202?alt=media&token=fcba57df-e252-47c2-be92-7836bd97e6fe";     postdate = 1502242913081;     price = 23;     private = 0;     title = "title ";     type = type;     useruid = 4bjurh5ffnoub2d4ohgfrqem7il2;     width = 118; }) snapshot: optional({     description = "hey ";     height = 82;     imageurl = "https://firebasestorage.googleapis.com/v0/b/medici-b6f69.appspot.com/o/art%2f4bjurh5ffnoub2d4ohgfrqem7il2%2f04b00727-2ae4-41e3-bca3-3980182c7f67?alt=media&token=cc1d6a92-1625-453c-bf1f-2ec84d6df51a";     postdate = 1503341277594;     price = 23;     private = 0;     title = "title ";     type = modern;     useruid = 4bjurh5ffnoub2d4ohgfrqem7il2;     width = 124; })        dic: ["height": 87, "private": 0, "width": 71, "postdate": 1498921599547, "description": yes , "title": yes , "imageurl": https://firebasestorage.googleapis.com/v0/b/medici-b6f69.appspot.com/o/art%2f4bjurh5ffnoub2d4ohgfrqem7il2%2fb6e2a9f0-c409-4732-b6d9-14382e6796f5?alt=media&token=32992b9c-4a08-456d-8950-119f681b4cdc, "useruid": 4bjurh5ffnoub2d4ohgfrqem7il2, "price": 23, "type": modern] dic: ["artwidth": 123, "height": 85, "private": 0, "artheight": 85, "description": yes , "postdate": 1498921623601, "width": 123, "imageurl": https://firebasestorage.googleapis.com/v0/b/medici-b6f69.appspot.com/o/art%2f4bjurh5ffnoub2d4ohgfrqem7il2%2f16280189-5aea-47cb-9251-c95635ffe56c?alt=media&token=8198df4e-da8c-4883-b278-fc7c14730f69, "title": blacks don’t crack , "price": 23, "type": abstract, "useruid": 4bjurh5ffnoub2d4ohgfrqem7il2] dic: ["artwidth": 11, "height": 81, "private": 0, "artheight": 81, "description": yes , "postdate": 1502242913081, "width": 118, "imageurl": https://firebasestorage.googleapis.com/v0/b/medici-b6f69.appspot.com/o/art%2f4bjurh5ffnoub2d4ohgfrqem7il2%2f305fde5c-1c5c-4abd-b4a1-4fa224421202?alt=media&token=fcba57df-e252-47c2-be92-7836bd97e6fe, "title": title , "price": 23, "type": type, "useruid": 4bjurh5ffnoub2d4ohgfrqem7il2] dic: ["height": 82, "private": 0, "width": 124, "postdate": 1503341277594, "description": hey , "title": title , "imageurl": https://firebasestorage.googleapis.com/v0/b/medici-b6f69.appspot.com/o/art%2f4bjurh5ffnoub2d4ohgfrqem7il2%2f04b00727-2ae4-41e3-bca3-3980182c7f67?alt=media&token=cc1d6a92-1625-453c-bf1f-2ec84d6df51a, "useruid": 4bjurh5ffnoub2d4ohgfrqem7il2, "price": 23, "type": modern] 

could please attach output of print(dictionary) , print(snapshot.value) before calling artviewmodelcontroller.parse(dictionary)?

var arts = [art?]() print(dictionary)      // -> output #1 print(snapshot.value)  // -> output #2 if let art = artviewmodelcontroller.parse(dictionary) {     arts.append(art) [...]