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iOS

Posted by Nicholas poulos
Nicholas poulos
1,291 Points

How can I measure the time in minutes from when my app was closed to when it was reopened?

How can I measure the time in minutes from when my app was closed to when it was reopened?

I'm basically making a pet-type app and need to determine how long the user has "neglected" the pet for so that it can affect the stat's of the pet.

I'm assuming I'd need to take a time stamp of when the app is closed and then compare it to a fresh timestamp of when it was reopened but I'm having a bit of trouble.

I have tried saving a timestamp as an NSUserDefault but I can't get something to work with.

Any help would be amazing. I'm thinking NSTimeIntervalSince1970 might be useful but there could be a much easier way?

I'm using Swift btw. :)

1 Answer

Steve Hunter
Steve Hunter
57,712 Points
Steve Hunter
Steve Hunter
57,712 Points

You need to use something that persists data - so you can store a timestamp (TimeIntervalSince1970 is fine) in the device rather than in a variable. On reopening the app, the stored value can be compared to "now" to give you your 'closed duration'. I'm guessing the a SQLite database would be the best way of delivering this functionality; indeed SQLite would open up many additional storage options that may be of use for your project.

I don't recall having done this in Swift, unfortunately, although I'm sure the documentation will assist.