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iOS

Jialong Zhang
Jialong Zhang
9,821 Points
Posted by Jialong Zhang
Jialong Zhang
9,821 Points

I want to execute a function after certain seconds, but not working with the code below"

Why does value is always 0? if statement or perhaps while statement is not working with DispatchQueue

import UIKit

var value = 0

func add(){
    value += 1
    print("new value: \(value)")
}

if value < 21 {
    DispatchQueue.main.asyncAfter(deadline: .now() + 1.0, execute:{
        add()
    })
    print("new value: \(value)")
}

1 Answer

Magnus Hållberg
Magnus Hållberg
17,232 Points
Magnus Hållberg
Magnus Hållberg
17,232 Points

First of all I'm pretty sure you will have to format the "now()" result since it will hold date and time, otherwise it wont know what you are referring to when you want to add 1 to it. Also I cant see how the "value" variable will change unless you use your if statement in a loop or function, now its just an if statement that will run one time and at this point wont trigger the add function that will add 1 to value. That is why value is always 0, it newer changes.