SetNeedsDisplay not working

Question

I saw many threads related to this issue, but none addresses my case (I think).

My case should be simple, I have a Custom UIView in my controller, from my c

Answer 1

I think the correct way to use it is:

[self setNeedsDisplay:YES]; 

Although I always have problems to get that working :(

Answer 2

After alot of testing, I saw something related to threads and the fact setNeedsDisplay should only be called in the mainThread...besides I never started a separeted thread in this classes, the class that raised the Notification was in a secondary thread...and aparently this was causing the issue...

to Solve it I just forced setNeedsDisplay to be called in the main thread..

dispatch_async(dispatch_get_main_queue(), ^{
            [self setNeedsDisplay];  
});

Swift 3:

DispatchQueue.main.async { [weak self] in
    self?.setNeedsDisplay()
}