Wait for completion block of writeImageToSavedPhotosAlbum by semaphore

Question

In my app I open the camera by a picker and after the photo has been taken I\'d like to safe it by the following method the assets library. The method freezes after the call

Answer 1

Do not wait. Never, never do what you are doing. You are failing to understand what "asynchronous" is about. It means that you are called back when it's all over in the completion block. So that is where you perform the next step.

Do NOT try to return a value from a method that obtains that value in an asynchronous completion block.

So, here, in writeImageToSavedPhotosAlbum:'s completion block, that is where you receive retAssestURL. So if there is a further step, now do it, there, in the completion block. This could involve calling another method or whatever you like, but the point is, things will now happen in the correct order.

And above all, Do NOT use semaphores (or other trickery) to try to turn asynchronous into synchronous. Asynchronous things are asynchronous for a reason. Use the framework, don't fight it. (Actually, what you are doing with semaphores here is not just fighting the framework but spitting in its eye.)