Perform a Block after Delay
- (void)performBlock:(void (^)(void))block afterDelay:(NSTimeInterval)delay
{
int64_t delta = (int64_t)(1.0e9 * delay);
dispatch_after(dispatch_time(DISPATCH_TIME_NOW, delta),
dispatch_get_main_queue(), block);
}[self performBlock: ^{
//Lines of code in block to execute
} afterDelay: 0.5f];
