I wrote an application that use MKMapView. This application use a timer to update some information on screen. Actually, when user touch the map and start the drag, the timer isn't fired anymore until the user release the touch. I notice that with the new iOS 6, this problem disappears. However I need to support also iOS 5. I haven't figure out if only timers aren't fired or if no events are processed at all. Any idea?
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Ok I found the solution here: UIScrollView pauses NSTimer until scrolling finishes
Basically you have to put the NSTimer in it's own run loop.
0
Hmm, that would suggest that the timers and the touch processing code are being handled by the same runloop, or possibly that the touches are blocking so when the timer completion code tries to run, it can't. Try using asynchronous blocks with completion handlers to run your timers.
- (void)startTimerInBackground {
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^(void) {
//Start timer here, set completion method to be called
NSTimer *t = [NSTimer scheduledTimerWithTimeInterval: 2.0
target: self
selector:@selector(timerCompletionMethod:)
userInfo: nil repeats:NO];
});
}
- (void)timerCompletionMethod:(NSTimer *)timer {
//Switch back to main thread here for completion code
dispatch_async(dispatch_get_main_queue(), ^(void) {
});
}
See if that helps, do note though that timers are not reliable, and if you need very accurate timing you should probably look at alternatives, there is some very good info here:
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Sam Clewlow
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Unfortunately it doesn't works. The 'timerCompletionMethod' is not called at all. I have also tried every other methods suggested in the link you provide, but the problem still occurs. Look like that the runloop is blocked during all the dragging/zooming operation! – AGPX Oct 07 '12 at 14:11