Performing tasks sequentially in Swift [duplicate] - ios

Question

This question already has answers here:
Returning data from async call in Swift function
(13 answers)
Closed 4 years ago.
I'm trying to verify a login and return a boolean value from my function accordingly, but my return statement keeps getting executed before the web service function is completed, even if I use an async method. I am using both Alamofire and SwiftyJSON.
I'm attaching my code below. Any help would be appreciated!
Thanks.
func checkUs (name: String, password: String) -> Bool
{
bool authen = false
DispatchQueue.global(qos: .userInitiated).async {
let jsonDic : [String: String] = ["email": name, "pass": password]
Alamofire.request("enter URL here", method: .post, parameters: jsonDic, encoding: JSONEncoding.default, headers: nil).responseJSON { (response) in
switch(response.result) {
case .success(let sentJSON):
let gotJSON = JSON (sentJSON)
print (gotJSON[0]["status"].boolValue)
authen = gotJSON[0]["status"].boolValue
case .failure(let err):
print(err)
}
print ("First ", authen)
}
}
print ("Second", authen)
return authen
//return true
Log Output:
Second false
true
First true

Answer 1

You need completion , also Alamfire runs asynchronously no need for global queue
func checkUs (name: String, password: String,completion: #escaping (_ status: Bool,_ err:Error?) -> Void) {
bool authen = false
let jsonDic : [String: String] = ["email": name, "pass": password]
Alamofire.request("enter URL here", method: .post, parameters: jsonDic, encoding: JSONEncoding.default, headers: nil).responseJSON { (response) in
switch(response.result) {
case .success(let sentJSON):
let gotJSON = JSON (sentJSON)
print (gotJSON[0]["status"].boolValue)
authen = gotJSON[0]["status"].boolValue
completion(authen,nil)
case .failure(let err):
print(err)
completion(authen,err)
}
print ("First ", authen)
}
print ("Second", authen)
}
//
call it like this
self.checkUs(name: "endedName", password: "sendedPassword") { (status, error) in
if let err = error {
}
else
{
}
}