I have an app where content is displayed to the user. I now want to find out how many seconds a user actually views that content for. So in my header file, I've declared an
NSDate *startTime;
NSDate *endTime;
Then in my viewWillAppear
startTime = [NSDate date];
Then in my viewWillDisappear
endTime = [NSDate date];
NSTimeInterval secs = [endTime timeIntervalSinceDate:startTime];
NSLog(@"Seconds --------> %f", secs);
However, the app crashes, with different errors sometimes. Sometimes it's a memory leak, sometimes it's a problem with the NSTimeInterval, and sometimes it crashes after going back to the content for a second time.
Any ideas on to fix this?
since you are not using ARC, when you write
startTime = [NSDate date];
you do not retain startTime
, so it is deallocated before -viewWillDisappear
is called. Try
startTime = [[NSDate date] retain];
Also, I recommend to use ARC. There should be much less errors with memory management with it, than without it