Android Question Using DateTime.ListenToExternalTimeChanges

[dbprogramer]

I can't find any examples of how to actually use this feature. My app gives a daily reminder at the time set by the user then it sets the time for the next reminder (24 hours later). But if there is a time change, (DST or time zone change) then I can't figure out a way for my app to know that before the scheduled time and then it might be off one or more hours off. Where do I use DateTime.ListenToExternalTimeChanges -- does this continue to listen even if the program is not running? Do I put it in a service module that starts at reboot? (I found this brief example but I can't figure out how to make this work if my program is not currently running when the time changes -- https://www.b4x.com/android/forum/t...value-on-androidthings-app.75072/#post-476634) Once a time change would trigger then I assume I need to check current time and recalculate how much time until the reminder/notification is supposed to happen. Thanks for your help.

 

[Erel]

does this continue to listen even if the program is not running?

No.

You need to do two things:
1. Call DateTime.ListenToExternalTimeChanges in Service_Create of the starter service.
2. Create a static intent filter that listens to this action: "android.intent.action.TIMEZONE_CHANGED" (don't use the starter service for this).

The intent filter will cause your app to start when the time zone changes.