If a WP8 Lock Screen image changes…

and there’s no-one there to see it, did it really happen?

Our app, Terminator has been updated for Windows Phone 8, and now supports wide tiles, and can also be the lock screen provider.

However, we’ve noticed that if you don’t look at the lock screen every half an hour, occasionally, the image displayed is out of date, but if you download the images stored in isolated storage has been updated.

We believe this is caused by the A/B switching algorithm suggested on MSDN.

Let’s say it’s 9:00, and the first image runs, so we update image A
At 9:30, the run again, and generate image B.

This continues every half an hour, so when I go to bed at 23:00, when I get up and look at my screen at 6:00 I see the image generated at 23:00.

Looks like we need to find another algorithm, probably creating a new file based on clock ticks, and then deleting all of the old files, so we generate a new file each time.

Of course, we now have the problem that we may fill up the users phone with abandoned files if anything goes wrong, which is a subject I’ll discuss soon.