There is some old code I am processing. Following are two lines (old code) which I am not able to convert or rather understand :
let dispatchTime = dispatch_time(dispatch_time_t(DispatchTime.now()), Int64(seconds * Double(NSEC_PER_SEC)))
dispatch_after(dispatchTime, dispatch_get_main_queue(), block)
Now, to make it work in Swift 4.x , this is what I did for line 1 :
let dispatchTime = DispatchTime(uptimeNanoseconds: UInt64(Int64(seconds * Double(NSEC_PER_SEC))))
I made this conversion on the basis of initialiser description as mentioned here :
Creates a time relative to the system clock that ticks since boot.
Since they say that it creates a relative time , DispatchTime.now()
is already considered. Not to mention, I might be wrong. Please do correct me.
For the second line, I am unaware as to how to pass DispatchTime
as an argument in DispatchAfter
.
This is what you want in Swift 3+:
let seconds = 2.0
// dispatchTime 2 seconds from now:
let dispatchTime: DispatchTime = DispatchTime.now() + seconds
DispatchQueue.main.asyncAfter(deadline: dispatchTime) {
// code to be executed
}
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