Cannot return items in a string array

Question

I'm very new to Parse and Swift and I have this project I am working on and I am trying to create a search bar that displays all the items from the key "names" from my Parse database.

I have created this function that is supposed to take all the names and return them in a string array. But instead, the array never gets filled and all I get as a return is [].

class Offices {
    var name: String
    var phone: String
    var location: String
    
    init(name: String = "def_name", phone: String = "def_phone", location: String = "def_location") {
        self.name = name
        self.phone = phone
        self.location = location
    }
    func retrieveName() -> [String] {
        var models = [String]()
        let queries = PFQuery(className: "Directory")
        queries.findObjectsInBackground { (object, error) in
            if let error = error {
                // The query failed
                print(error.localizedDescription)
            } else if let object = object {
                // The query succeeded with a matching result
                for i in object{
                    models.append(i["name"] as? String ?? self.name)
                }
                
            } else {
                // The query succeeded but no matching result was found
            }
            
        }
        return models
    }

https://stackoverflow.com/questions/25203556/returning-data-from-async-call-in-swift-function — Martin R, Jan 24 '21 at 20:58
Does this answer your question? [Returning data from async call in Swift function](https://stackoverflow.com/questions/25203556/returning-data-from-async-call-in-swift-function) — timbre timbre, Jan 24 '21 at 21:40

score 2 · Accepted Answer · answered Jan 24 '21 at 21:00

findObjectsInBackground method is asynchronous. So you should change retrieveName function as below:

class Offices {
    var name: String
    var phone: String
    var location: String
    
    init(name: String = "def_name", phone: String = "def_phone", location: String = "def_location") {
        self.name = name
        self.phone = phone
        self.location = location
        
        // I call retrieveName here for example. You can call it where you want.
        retrieveName() { (success, models) in
            if success {
                print(models)
            } else {
                print("unsuceess")
            }
        }
    }

    func retrieveName(completion: @escaping (_ success: Bool, _ models: [String]) -> Void) {
        var models = [String]()
        let queries = PFQuery(className: "Directory")
        queries.findObjectsInBackground { (object, error) in
            if let error = error {
                // The query failed
                print(error.localizedDescription)
                completion(false, [])
            } else if let object = object {
                // The query succeeded with a matching result
                for i in object{
                    models.append(i["name"] as? String ?? self.name)
                }
                completion(true, models)
            } else {
                completion(true, [])
                // The query succeeded but no matching result was found
            }
        }
    }
}

Not really sure what happens with async functions but it worked, thanks! — c0mp13x, Jan 25 '21 at 13:13
I suggest you reading below guide. Specially `Escaping Closures` section. https://docs.swift.org/swift-book/LanguageGuide/Closures.html — Mohammad Eslami, Jan 25 '21 at 19:05

Cannot return items in a string array

1 Answers1