[Bug][Uwp] TextValidationBehavior inconsistent when not setting ValidStyle

[Brosten]

Description

I implemented email validation, following this example,

However, on UWP it isn't really consistent, as long as a "ValidStyle" isn't added. Shoulden't the "Valid" style default to whatever style the control had without the behaviour?

Steps to Reproduce

1. Add a validator like the linked example and run the code
2. Add "test@test" as input text
3. Unfocus (Text becomes red, correct!)
4. Change text to "test@test.se"
5. Unfocus (Text becomes black, correct!)
6. Focus back (Text becomes red, feels incorrect!)

Expected Behavior

A black text when setting the focus back

Actual Behavior

A red text

Basic Information

• Version with issue:
  1.0.0-pre5
• Last known good version:
  ?
• IDE:
• Platform Target Frameworks:
  • iOS: Seems to work
  • Android: Seems to work
  • UWP: 1903
• Android Support Library Version:
• Nuget Packages:
• Affected Devices:

Workaround

If you set a "ValidStyle" with black text, it's correctly set back to black, when focusing

[AndreiMisiukevich]

Hi @Brosten Thanks for this report!

Does it work as expected on other platforms (Android / iOS)?

[AndreiMisiukevich]

Also, I wonder, is "Focused" event raised on step 6

[Brosten]

Yes, it does work fine on android and ios.
Yes, Focused event is triggered on the Entry control on step 6.

[AndreiMisiukevich]

@pictos would you like to debug this issue on UWP?

[pictos]

I'll do it asap

[AndreiMisiukevich]

if it becomes red, it means that "IsValid = False" for some reason

[pictos]

I'm able to reproduce the behavior

[pictos]

I found the issue. The ValidStyle is null, so on UWP (at least) the entry maintains the last valid Style.

if we add a ValidStyle everything works as expected.

So my question is. Is it a bug or a feature?