CADisplayLink stops updating when UIScrollView scrolled

Question

Title is quite self explanatory, but I have some animation being done in a loop triggered by CADisplayLink. However, as soon as I scroll a UIScrollView I have added to my view hierarchy, the animation stops immediately, only to return again when scrolling has completely stopped and come to a standstill....

Anyway to cancel this behaviour?

Answer 1

Run the display link (using -addToRunLoop:forMode:) on another thread with another run loop. So create a new thread, create a run loop on that thread, and run the CADisplayLink on that thread/run loop.

Answer 2

You can also mitigate the effects of this issue by using NSRunLoopCommonModes instead of NSDefaultRunLoopModes:

[displayLink addToRunLoop:[NSRunLoop currentRunLoop]
                  forMode:NSRunLoopCommonModes];

Answer 3

NSRunLoopCommonModes seems to mess with the bounciness and continuous nature of the uiscrollview.

Answer 4

I found that if I set the frame interval to 2 instead of 1 (so 30 frames a second) everything works fine. So what I'm doing is setting it to 2 when my popover comes up and resetting it to 1 when it dismisses.