Android Timer which works on both background and foreground -

i'm working on app track students' studying time. student can press start button , start studying. , stop when finish studying.

when screen on or phone plugged in,the text view , progress bar updating every second .(i means works fine) when screen off,updating textview , progress stopped after 10 seconds of sleeping phone. think may activity pausing. right?

i tested using:

1. partial wakelock
2. service

both of these ways make battery drains. there idea case? thanks.

you should use service class, work in background when activity puased

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