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iOS

Posted by German Espitia
German Espitia
4,578 Points

NSTimer to fire when day ends?

Hi,

I am trying to let users complete a task once a day, so when the day ends, the task is enabled again.

Would using NSTimer be the best way to go about this?

1 Answer

Stone Preston
Stone Preston
42,016 Points

I dont think that will work. The app would have to be in use constantly for the timer to work right ( I think). You might try using NSUserDefaults to store the date of the last app open. Then compare that date stored in defaults to the current date. if the current date is past midnight of the stored date, reset the task. something like that is what you are most likely going to have to do

German Espitia
German Espitia
4,578 Points

Stone, thanks for your input.

I tried the timer and quickly realized that it was not going to work as you said. After Googling around for a bit, I found UIApplicationSignificantTimeChangeNotification[1] which as Apple says:

"Posted when there is a significant change in time, for example, change to a new day (midnight), carrier time update, and change to or from daylight savings time. This notification does not contain a userInfo dictionary."

I think it was just what I needed.

[1]https://developer.apple.com/library/ios/documentation/uikit/reference/UIApplication_Class/Reference/Reference.html

Stone Preston
Stone Preston
42,016 Points

hmm. I think you may have the same problem with that solution as well. The app will have to be running for the notification to be received. if the app is not running, the notification wont be received and your reset will not run at all