Why is my Bool value changed to false after exiting the nested method? [duplicate] - ios

Question

This question already has answers here:
Returning data from async call in Swift function
(13 answers)
Closed 6 years ago.
I'm trying to perform a login as follows:
func login()->Bool
{
var result:Bool = false;
var request = URLRequest(url: URL(string: "http://something.com/authenticate")!)
request.httpMethod = "POST"
let postString = "email=\(usernameField.text!)&password=\(passwordField.text!)"
print("email=\(usernameField.text!)&password=\(passwordField.text!)")
request.httpBody = postString.data(using: .utf8)
request.setValue("application/x-www-form-urlencoded", forHTTPHeaderField: "Content-Type")
let task = URLSession.shared.dataTask(with: request) { data, response, error in
guard let data = data, error == nil else {
// check for fundamental networking error
print("error=\(error)")
result = false;
return
}
if let httpStatus = response as? HTTPURLResponse, httpStatus.statusCode != 200 {
// check for http errors
print("statusCode should be 200, but is \(httpStatus.statusCode)")
print("response = \(response)")
print("request = \(request)")
result = false
}
let responseString = String(data: data, encoding: .utf8)
result = true;
print("responseString = \(responseString)")
self.processResponse(jsonData:data)
}
task.resume()
return result;
}
My 'result' variable always resolves to false even if the line result = true is hit.
How to set it to true inside the nested method?

Answer 1

You are using Block and blocks are not call at the same time when you are calling "login" method. So, you need to implement blocks for receive result. Try Following Code :
func login(block:((Bool) -> Void)!)
{
var result:Bool = false;
var request = URLRequest(url: URL(string: "http://something.com/authenticate")!)
request.httpMethod = "POST"
let postString = "email=\(usernameField.text!)&password=\(passwordField.text!)"
print("email=\(usernameField.text!)&password=\(passwordField.text!)")
request.httpBody = postString.data(using: .utf8)
request.setValue("application/x-www-form-urlencoded", forHTTPHeaderField: "Content-Type")
let task = URLSession.shared.dataTask(with: request) { data, response, error in
guard let data = data, error == nil else {
// check for fundamental networking error
print("error=\(error)")
result = false;
block(result)
return
}
if let httpStatus = response as? HTTPURLResponse, httpStatus.statusCode != 200 {
// check for http errors
print("statusCode should be 200, but is \(httpStatus.statusCode)")
print("response = \(response)")
print("request = \(request)")
result = false
}
if data != nil
{
result = true
}
let responseString = String(data: data, encoding: .utf8)
print("responseString = \(responseString)")
self.processResponse(jsonData:data)
block(result)
}
task.resume()
}