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Alex Rivera
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I have a UIScrollView that has a set of images loaded side-by-side inside it. You can see an example of my app here: http://www.42restaurants.com . My problem comes in with memory usage. I want to lazy load the images as they are about to appear on the screen and unload images that aren't on screen. As you can see in the code I work out at a minimum which image I need to load and then assign the loading portion to an NSOperation and place it on an NSOperationQueue. Everything works great apart from a jerky scrolling experience. I don't know if anyone has any ideas as to how I can make this even more optimized, so that the loading time of each image is minimized or so that the scrolling is less jerky. - (void)scrollViewDidScroll:(UIScrollView *)scrollView{ [self manageThumbs]; } - (void) manageThumbs{ int centerIndex = [self centerThumbIndex]; if(lastCenterIndex == centerIndex){ return; } if(centerIndex >= totalThumbs){ return; } NSRange unloadRange; NSRange loadRange; int totalChange = lastCenterIndex - centerIndex; if(totalChange > 0){ //scrolling backwards loadRange.length = fabsf(totalChange); loadRange.location = centerIndex - 5; unloadRange.length = fabsf(totalChange); unloadRange.location = centerIndex + 6; }else if(totalChange < 0){ //scrolling forwards unloadRange.length = fabsf(totalChange); unloadRange.location = centerIndex - 6; loadRange.length = fabsf(totalChange); loadRange.location = centerIndex + 5; } [self unloadImages:unloadRange]; [self loadImages:loadRange]; lastCenterIndex = centerIndex; return; } - (void) unloadImages:(NSRange)range{ UIScrollView *scrollView = (UIScrollView *)[[self.view subviews] objectAtIndex:0]; for(int i = 0; i < range.length && range.location + i < [scrollV
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