(Swift, macOS, Storyboards)
I can read a JSON from an URL. I would like to know when I can access the information. To be able to go from one function after the other. It seems that "completion" does not work with JSON? or perhaps I am doing something wrong?
I give a simplified example: I try to get the JSON information in func first() and then do something with that information in func second()
var result2 = "empty"
func first(completion: ()->()) {
let url = URL(string: "https://jsonplaceholder.typicode.com/users")!
URLSession.shared.dataTask(with: url) { data, _, _ in
if let data = data {
let result = try? JSONDecoder().decode([User].self, from: data)
self.result2 = result![0].name
}
}.resume()
completion()
}
func second() {
//do something after first()
print (result2)
}
@IBAction func button1(_ sender: NSButton) {
first {
second()
}
}
You are putting completion() at the wrong place:
func first(completion: @escaping ()->()) { //<-
let url = URL(string: "https://jsonplaceholder.typicode.com/users")!
URLSession.shared.dataTask(with: url) { data, _, _ in
if let data = data {
let result = try? JSONDecoder().decode([User].self, from: data)
self.result2 = result![0].name
completion() //<- here
}
}.resume()
//completion() //<- Not here
}
