Check container recreation in OnBackgroundActivated

[bartlannoeye]

PR checklist

Quick summary of changes

• Which issue does this PR relate to? Fixes [Prism] Background activation should not recreate container #2632
• Anything that requires particular review or attention? Check explanation in issue to see if I forgot something.
• Do all automated tests pass? No reference found in tests, didn't rerun whole suite.
• Have automated tests been added for new features? No
• Have you raised issues for any needed follow-on work? No
• Have docs been updated? No reference found
• If breaking changes or different ways of doing things have been introduced, have they been communicated widely? This probably should be added to the changelog for existing apps with Prism and background tasks.

[crutkas]

this should be on the main readme i think.

[sibille]

Thanks Bart!! Did a bit of research where this came from, and saw this was initially added in PR #1606, won't this lead to regression in case the app is terminated?

[bartlannoeye]

Since the background task is in-process, it's terminated as well and can't re-activate a terminated app. Am I correct?

I've tested following cases (manually through VS lifecycle states):

• background task (on running app)
• suspend - resume
• suspend - background task - resume
• suspend and shutdown - launch

All worked fine.

[bartlannoeye]

Looks like there's one more step to be tested (see issue). I'll look at it tonight, can stay open for now.

[bartlannoeye]

Quick update: making progress on this, but checking a few more items to see for the best solution. Out of town for 2 days, so picking this up again over the weekend.

[sibille]

@bartlannoeye, what's the status for this pr?

[bartlannoeye]

Hey @sibille, the complexity of trying to make it work with the current release, combined with multiple events (attending and/or speaking) resulted in taking a bit longer. I've done a "best-effort" fix which handles 95% of all use cases and described the last edge case (which should rarely happen) in the linked issue. We'll have to take this last one in our next Prism release.

It's an improvement over the current code in WTS, so if the team agrees, I would suggest to merge this PR and we'll do our best to get the next release out the door asap.

[sibille]

Thanks @bartlannoeye, sounds good to me!