ListDetailsView: unfocus details on selection changed

[Rosuavio]

Fixes #3546 #4244

PR Type

What kind of change does this PR introduce?

What is the current behavior?

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PR Checklist

Please check if your PR fulfills the following requirements:

• Tested code with current supported SDKs
• New component
  • Pull Request has been submitted to the documentation repository instructions. Link:
  • Added description of major feature to project description for NuGet package (4000 total character limit, so don't push entire description over that)
  • If control, added to Visual Studio Design project
• 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
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• Tests for the changes have been added (for bug fixes / features) (if applicable)
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• Contains NO breaking changes

Other information

[ghost]

Thanks RosarioPulella 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 🙌

[Rosuavio]

Working on writing unit tests for this. Note: As of 0c7cf48 its not working yet.

[Rosuavio]

Got it working as of bb6233e, just need to write tests and see if it can simplified.

[michael-hawker]

StyleCop: D:\a\1\s\UnitTests\UnitTests.UWP\UI\Controls\Test_ListDetailsView_UI.cs(21,30): error SA1303: Const field names should begin with upper-case letter. [D:\a\1\s\UnitTests\UnitTests.UWP\UnitTests.UWP.csproj]

[XAML-Knight]

I inherited this PR, after @RosarioPulella sailed away on a new venture.

Let's scorecard where we are with ListDetailsView:

• This PR ListDetailsView: unfocus details on selection changed #4222 - this unit test is failing. You can visually see the problem (this is a UI test), where a modified value in a textbox is not saved properly, before navigating away and then coming right back to it. My suspicion is that the data binding inside the test is not set up properly, which would then cause the test to fail.
• PR ListDetailsView unfocus content on SelectedIndex changed. #4255 - these unit tests are passing
• Issue ListDetailsView navigation data loss #3546 - @RosarioPulella felt that this issue could be re-opened, even though it was closed (by ListDetailsView unfocus content on SelectedIndex changed. #4255)
  • Link: ListDetailsView navigation data loss #3546 (comment)