Bug 58289 - UI displays different views than visible in modal stack
Summary: UI displays different views than visible in modal stack
Alias: None
Product: Forms
Classification: Xamarin
Component: iOS ()
Version: unspecified
Hardware: PC Mac OS
: Normal normal
Target Milestone: ---
Assignee: Bugzilla
Depends on:
Reported: 2017-07-21 08:32 UTC by arno.schneider
Modified: 2017-07-28 02:58 UTC (History)
3 users (show)

Tags: pushmodalasync, ac
Is this bug a regression?: ---
Last known good build:

Example project (16.33 KB, application/zip)
2017-07-21 08:32 UTC, arno.schneider

Notice (2018-05-24): bugzilla.xamarin.com is now in read-only mode.

Please join us on Visual Studio Developer Community and in the Xamarin and Mono organizations on GitHub to continue tracking issues. Bugzilla will remain available for reference in read-only mode. We will continue to work on open Bugzilla bugs, copy them to the new locations as needed for follow-up, and add the new items under Related Links.

Our sincere thanks to everyone who has contributed on this bug tracker over the years. Thanks also for your understanding as we make these adjustments and improvements for the future.

Please create a new report for Bug 58289 on Developer Community or GitHub if you have new information to add and do not yet see a matching new report.

If the latest results still closely match this report, you can use the original description:

  • Export the original title and description: Developer Community HTML or GitHub Markdown
  • Copy the title and description into the new report. Adjust them to be up-to-date if needed.
  • Add your new information.

In special cases on GitHub you might also want the comments: GitHub Markdown with public comments

Related Links:

Description arno.schneider 2017-07-21 08:32:15 UTC
Created attachment 23707 [details]
Example project

I discovered a situation with Xamarin Forms and iOS I feel is not ideal:

Example project pushes three modal views shortly after each other with the following results:
-> ModalPushing is called three times, ModalPushed only two times
-> there are three DIFFERENT views in the modal stack
-> there are three views displayed on the iPad, but the second and third view are IDENTICAL
-> if you manually pop the top view you see the identical view below it (so there are three views displayed and not only two but ModalPushed is never called a third time)
-> if you try to pop the top view with an awaited PopModalAsync any code after it won't be executed, if you pop it without await code after it is executed

I know that in this example project I could just easily await the PushModalAsync, but I discovered the situation in a different context and I feel that situation should never occur at all.
Comment 1 Paul DiPietro [MSFT] 2017-07-21 16:51:58 UTC
I don't believe this is necessarily an iOS exclusive issue, but it at least occurs with the nightly build as well.