Fixed a crash with the items list animations in Sample app

[Sergio0694]

Fixes #3701

PR Type

What kind of change does this PR introduce?

• Bugfix (sample app)

What is the current behavior?

There is a crash in the items animations when looking for samples. This was unrelated from the actual animation APIs, and the crash was happening because the parent of the DropShadowPanel for each item was actually null if the items were being swapped by a text change while one was animated, so the animation was being invoked on null, resulting in a crash. I've just added two checks to skip the animation out in case the whole list is being refreshed, as the item containers would all be discarded anyway.

What is the new behavior?

The crash is fixed.

PR Checklist

Please check if your PR fulfills the following requirements:

• Tested code with current supported SDKs
• Pull Request has been submitted to the documentation repository instructions. Link:
• Sample in sample app has been added / updated (for bug fixes / features)
  • Icon has been created (if new sample) following the Thumbnail Style Guide and templates
• New major technical changes in the toolkit have or will be added to the Wiki e.g. build changes, source generators, testing infrastructure, sample creation changes, etc...
• Tests for the changes have been added (for bug fixes / features) (if applicable)
• Header has been added to all new source files (run build/UpdateHeaders.bat)
• Contains NO breaking changes

[ghost]

Thanks Sergio0694 for opening a Pull Request! The reviewers will test the PR and highlight if there is any conflict or changes required. If the PR is approved we will proceed to merge the pull request 🙌

[Kyaa-dost]

Thanks @Sergio0694 ! Looks good to me 🚀

[ghost]

Hello @Kyaa-dost!

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