Adding delay between execution of two following lines

Question

I need to add a delay between the execution of two lines in a(same) function. Is there any favorable option to do this?

Note: I don't need two different functions to do this, and the delay must not affect other functions' execution.

eg:

line 1: [executing first operation];

line 2: Delay                        /* I need to introduce delay here */

line 3: [executing second operation];

Any help is appreciable. Thanks in advance...

Answer 1

You can use gcd to do this without having to create another method

// ObjC

NSTimeInterval delayInSeconds = 2.0;
dispatch_time_t popTime = dispatch_time(DISPATCH_TIME_NOW, (int64_t)(delayInSeconds * NSEC_PER_SEC));
dispatch_after(popTime, dispatch_get_main_queue(), ^(void){
  NSLog(@"Do some work");
});

// Swift

DispatchQueue.main.asyncAfter(deadline: .now() + 2) {
    print("Do some work)
}

You should still ask yourself "do I really need to add a delay" as it can often complicate code and cause race conditions

Answer 2

You can use the NSThread method:

[NSThread sleepForTimeInterval: delay];

However, if you do this on the main thread you'll block the app, so only do this on a background thread.

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or in Swift

NSThread.sleepForTimeInterval(delay)

in Swift 3

Thread.sleep(forTimeInterval: delay)