Executefetchrequest Throw Fatal Error: Nsarray Element Failed to Match the Swift Array Element Type

executeFetchRequest throw fatal error: NSArray element failed to match the Swift Array Element type

I was able to reproduce your error message in the console. You get this message because you didn't set correctly your entity class name in the Core Data Model Editor (see image below).

Once done, you will be able to use your original code with Contact subClass. You can learn more about Core Data and namespaces here.

FetchRequest - NSArray element failed to match the Swift Array Element type - Swift 2.0

Solution

var voitures: [NSManagedObject]?  = [NSManagedObject]()

if (voitures!.count > 0) {

        let voiture: NSManagedObject = voitures![indexPath.row]

        print((voiture.valueForKey("nom") as? String))
    }

Thread 1: Fatal error: NSArray element failed to match the Swift Array Element type

Okay, I've found the reason of this error.
My messages array was being appended in another block of code with SBDUserMessages, and I wasn't cast them as exact type of message (as! SBDUserMessage).

The debugging really helped a lot. At some point I decided to call before the self.messages.append(newMessage) (where the crash actually occured), the messaged.removeAll(), and after that I've found out that everything works fine.

Firebase iOS Swift fatal error: NSArray element failed to match the Swift Array Element type

The issue is in your ChitObject class, specifially here:

bidders = snapshotValue["bidders"] as! [Bidder]

You would need to create an array of Bidders and assign that into bidders variable. Loop through the array you get from snapshotValue["bidders"] and create Bidders object for every value and assign that into a Swift array.

I have not workded with Firebase but something like this may work:

init(snapshot: FIRDataSnapshot) {
    let snapshotValue = snapshot.value as! [String: AnyObject]
    chitId = snapshotValue["chitId"] as! Int
    chitName = snapshotValue["chitName"] as! String
    startDate = snapshotValue["startDate"] as! String
    endDate = snapshotValue["endDate"] as! String
    chitTotalAmt = snapshotValue["chitTotalAmt"] as! Int
    chitTotalMonths = snapshotValue["chitTotalMonths"] as! Int
    if let biddersArray = snapshotValue["bidders"] as? [[String:Any]] {
        bidders = biddersArray.flatMap{Bidder(dict:$0)}
    }
    ref = snapshot.ref
}

EDITED:

class Bidder {

    var bidderId: Int
    var bidderName: String
    var bidderEmail: String
    var bidderPhone : String
    var modeOfPayment: Int
    var bidderBankName: String
    var bidderBankAcno: String
    var bidderIfscCode: String
    var paymentArray : [[String:String]]?
    var chitrefArray : [String]?
    var ref: FIRDatabaseReference?

    convenience init?(dict:[String:Any]) {
        guard let bidderId = dict["bidderId"] as? Int, let bidderName = dict["bidderName"] as? String, let bidderEmail = dict["bidderEmail"] as? String, let bidderPhone = dict["bidderPhone"] as? String, let modeOfPayment = dict["paymentType"] as? Int, let bidderBankName = dict["bankName"] as? String, let bidderBankAcno = dict["bankAccNumber"] as? String, let bidderIfscCode = dict["bankIFSC"] as? String else {
            return nil
        }
        self.init(bidderId: bidderId, bidderName: bidderName, bidderEmail: bidderEmail, bidderPhone: bidderPhone, modeOfPayment: modeOfPayment, bidderBankName: bidderBankName, bidderBankAcno: bidderBankAcno, bidderIfscCode: bidderIfscCode, paymentArray: [[]], chitrefArray: [])
    }

    init(bidderId: Int, bidderName: String,bidderEmail: String, bidderPhone: String, modeOfPayment: Int, bidderBankName: String, bidderBankAcno: String, bidderIfscCode: String,paymentArray:  [[String:String]], chitrefArray: [String]) {
        self.bidderId = bidderId
        self.bidderName = bidderName
        self.bidderEmail = bidderEmail
        self.bidderPhone = bidderPhone
        self.modeOfPayment = modeOfPayment
        self.bidderBankName = bidderBankName
        self.bidderBankAcno = bidderBankAcno
        self.bidderIfscCode = bidderIfscCode
        self.paymentArray = paymentArray
        self.chitrefArray = chitrefArray
        self.ref = nil
    }

    init(snapshot: FIRDataSnapshot) {
        let snapshotValue = snapshot.value as! [String: AnyObject]
        bidderId = snapshotValue["bidderId"] as! Int
        bidderName = snapshotValue["bidderName"] as! String
        bidderEmail = snapshotValue["bidderEmail"] as! String
        bidderPhone = snapshotValue["bidderPhone"] as! String
        modeOfPayment = snapshotValue["modeOfPayment"] as! Int
        bidderBankName = snapshotValue["bidderBankName"] as! String
        bidderBankAcno = snapshotValue["bidderBankAcno"] as! String
        bidderIfscCode = snapshotValue["bidderIfscCode"] as! String
        paymentArray = snapshotValue["paymentArray"] as? [[String : String]]
        chitrefArray = snapshotValue["chitrefArray"] as? [String]
        ref = snapshot.ref
    }

    func toAnyObject() -> Any {
        return [
            "bidderId" : bidderId,
            "bidderName" : bidderName,
            "bidderEmail": bidderEmail,
            "bidderPhone": bidderPhone,
            "modeOfPayment": modeOfPayment,
            "bidderBankName":bidderBankName,
            "bidderBankAcno": bidderBankAcno,
            "bidderIfscCode":bidderIfscCode,
            "paymentArray": paymentArray as Any,
            "chitrefArray" : chitrefArray as Any
        ]
    }

}

poet.books throw fatal error: NSArray element failed to match

My suggestion is to add an initializer to your Works class:

class Works {

    var nameWork = ""
    var workPoet = ""

    init(nameWork: String, workPoet: String) {
        self.nameWork = nameWork
        self.workPoet = workPoet
    }
}

Then you can use it like this:

let worksArray = booksDict[poet.poetName as String] as! NSArray
for work in worksArray {
    let dictionaryFromArray = work as! NSDictionary
    let workObject = Works(nameWork: dictionaryFromArray["nameWork"] as! String, workPoet: dictionaryFromArray["work"] as! String)
    poet.books.append(workObject)
}

poet.books throw fatal error: NSArray element failed to match

My suggestion is to add an initializer to your Works class:

class Works {

    var nameWork = ""
    var workPoet = ""

    init(nameWork: String, workPoet: String) {
        self.nameWork = nameWork
        self.workPoet = workPoet
    }
}

Then you can use it like this:

let worksArray = booksDict[poet.poetName as String] as! NSArray
for work in worksArray {
    let dictionaryFromArray = work as! NSDictionary
    let workObject = Works(nameWork: dictionaryFromArray["nameWork"] as! String, workPoet: dictionaryFromArray["work"] as! String)
    poet.books.append(workObject)
}

Why is executeFetchRequest not returning subclass objects when run under XCTest using Swift?

I had a similar question. Making my entity class public solves the issue and I get the right class type.(CoreData class miss match in unit test)

---

Related Topics