Fix for issue #13493

[laolarou726]

What does the pull request do?

This PR fixed an issue mentioned in #13493
For function UpdateContent(bool withTransition), this PR ensures that the Updated content is not in the last presented ContentPresenter, otherwise it will raise the exception mentioned in #13493

What is the current behavior?

Currently, in some cases, the new content is the content that TCC just presented. An exception will be raised.

What is the updated/expected behavior with this PR?

Now there will be no such issue.

Checklist

• Added unit tests (if possible)?
• Added XML documentation to any related classes?
• Consider submitting a PR to https://github.com/AvaloniaUI/avalonia-docs with user documentation

Fixed issues

• Fixes TransitioningContentControl issue #13493

[maxkatz6]

Can you add a test for this scenario? In TransitioningContentControlTests file.
This PR also broken some other tests there.

[laolarou726]

Can you add a test for this scenario? In TransitioningContentControlTests file. This PR also broken some other tests there.

I just fixed and now all the tests are passed. Also, I added one more test to verify the check is working. Could you please review it again? Thx!

[laolarou726]

Can any one help me to confirm that this PR is able to merge into the master? Thx.

[grokys]

Hi @laolarou726 - thanks for the PR! However looking at the test, it seems to pass even without the modified code in TransitioningContentControl. In addition when I run your repro (https://github.com/laolarou726/TCCExceptionTest) I don't see any exception there either.

The fix looks reasonable but I'd like to be able to confirm the problem first and I'm not sure why I'm unable to. Does the unit test fail for you if you remove the changes to TransitioningContentControl?

[laolarou726]

Hi @laolarou726 - thanks for the PR! However looking at the test, it seems to pass even without the modified code in TransitioningContentControl. In addition when I run your repro (https://github.com/laolarou726/TCCExceptionTest) I don't see any exception there either.

The fix looks reasonable but I'd like to be able to confirm the problem first and I'm not sure why I'm unable to. Does the unit test fail for you if you remove the changes to TransitioningContentControl?

Ohh sorry for the confusion, in the repo I replace the transitioningcontentcontrol to the fixed implementation "TCC". If you change all the TCC back to the TransitioningContentControl, the exception will occur. I'll just update the repo now.

[laolarou726]

@grokys I just updated the repro, and now the exception will shown. Please click the "Start" and wait for a few seconds. Then the exception will be thrown. https://github.com/laolarou726/TCCExceptionTest.

For the test, do you think it's ok to just remove it?

[laolarou726]

Hi @laolarou726 - thanks for the PR! However looking at the test, it seems to pass even without the modified code in TransitioningContentControl. In addition when I run your repro (https://github.com/laolarou726/TCCExceptionTest) I don't see any exception there either.

The fix looks reasonable but I'd like to be able to confirm the problem first and I'm not sure why I'm unable to. Does the unit test fail for you if you remove the changes to TransitioningContentControl?

@grokys Could you please check the repo again? Thx!

[laolarou726]

@grokys Could you please review the repro again? Thanks!