grand-central-dispatch Archives

In my app I have a function that makes an NSRURLSession and sends out an NSURLRequest using sesh.dataTaskWithRequest(req, completionHandler: {(data, response, error) In ...

May 30, 2022
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How do I dispatch_sync, dispatch_async, dispatch_after, etc in Swift 3, Swift 4, and beyond?

I have lots of code in Swift 2.x (or even 1.x) projects that looks like this: // Move to a background thread to ...

May 21, 2022
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GCD to perform task in main thread

I have a callback which might come from any thread. When I get this callback, then I would like to perform a certain ...

May 19, 2022
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Create singleton using GCD’s dispatch_once in Objective-C

If you can target iOS 4.0 or above Using GCD, is it the best way to create singleton in Objective-C (thread safe)? + ...

May 12, 2022
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How to create dispatch queue in Swift 3

In Swift 2, I was able to create queue with the following code: let concurrentQueue = dispatch_queue_create("com.swift3.imageQueue", DISPATCH_QUEUE_CONCURRENT) But this doesn’t compile in ...

May 7, 2022
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How do I write dispatch_after GCD in Swift 3, 4, and 5?

In Swift 2, I was able to use dispatch_after to delay an action using grand central dispatch: var dispatchTime: dispatch_time_t = dispatch_time(DISPATCH_TIME_NOW, Int64(0.1 ...

May 4, 2022
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NSOperation vs Grand Central Dispatch

I’m learning about concurrent programming for iOS. So far I’ve read about NSOperation/NSOperationQueue and GCD. What are the reasons for using NSOperationQueue over ...

May 4, 2022
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dispatch_after – GCD in Swift?

I’ve gone through the iBook from Apple, and couldn’t find any definition of it: Can someone explain the structure of dispatch_after? dispatch_after(<#when: dispatch_time_t#>, ...

April 30, 2022
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