Real time duration that game was minimized on android / ios

Hi, i want to calculate real time, for how long game was minimized in android / ios. For now, i'm coding in c# and using System.DateTime structure to get time (DateTime.UtcNow) when game was minimized and time when game was restored, and then i calculate the difference. The problem is, if you change phones date/time, then DateTime.UtcNow will return changed phones date also, so in the end i will have incorrect/cheated time, that game was minimized for. Is there a way to calculate somehow a real time, that game was minimized for on android/ios ? Using internet is not an option for me, also, other games are using some kind of background processes to calculate real time, you cant cheat on them by changing phones time, and also these games do not use internet time, but these are not made on unity. So is it possible to do that on unity for android/ios ?

 

Try starting a System.Diagnostics.Stopwatch in a background thread. That should get you a consistent time that always works, unless the phone OS isn't multi-tasking. In which case, they're probably not playing games on it, either.

 

Thanks, that worked good, just had to put Stopwatch timer.Start() into code, which is executed, when game is minimized, and timer.Stop() when game is resumed.

 

We have a problem - this method doesn't always work : when phone is active, then stopwatch timer is counting time and everything is ok, but if phone is put to sleep (which is always happening, if you are not using your phone), then stopwatch timer stops counting time, so this method doesn't really work. I was thinking about calling android native functions and getting phones uptime. Anyone knows a good tutorial, how to call android native functions from unity ? For now, i found another thing in unity - Time.realtimeSinceStartup, will be testing it for now.

Edit : Time.realtimeSinceStartup is bad too, it is not real time, its fake, it doesnt count time when phone is put to sleep. So i guess the only option is to write native android plugin and get system uptime.

 

We faced the same problem in our Company. the Stopwatch works correctly when the app goes to background, but when the system goes to sleep the Stopwatch stops ticking (approximately after one minute after screen lock). For iOS, our solution is to use the custom native plugin, that uses macOS/iOS native C function clock_gettime. This function used with theCLOCK_MONOTONIC clock should do the job for you. For more info see
http://www.manpagez.com/man/3/clock_gettime/ and
https://stackoverflow.com/questions/12488481/getting-ios-system-uptime-that-doesnt-pause-when-asleep. Currently not sure about the solution for Android. BUt the StopWatch behavior is probably a bug in Unity IL2CPP compiler and Stopwatch implementation. Going to create a new Issue on the Unity Issue tracker.