[iOS] Fix CollectionView issue selection multiple items

[jsuarezruiz]

Description of Change

Fix CollectionView issue with selection of multiple items on iOS.

Issues Resolved

• fixes [Bug] CollectionView initial selection is broken #13592

API Changes

None

Platforms Affected

• iOS

Behavioral/Visual Changes

None

Before/After Screenshots

Testing Procedure

Launch Core Gallery and navigate to the issue 13592. If both CollectionViews have items selected, the test has passed.

PR Checklist

• Targets the correct branch
• Tests are passing (or failures are unrelated)

[jsuarezruiz]

cc @Tommigun1980

[Tommigun1980]

cc @Tommigun1980

Thank you!

Fwiw a very similar problem happens with SelectionMode Single, does this fix that also? The repro project can be edited to use Single instead and it should show that error also.

Thank you again for fixing this!

[jfversluis]

Fwiw a very similar problem happens with SelectionMode Single, does this fix that also? The repro project can be edited to use Single instead and it should show that error also.

It would greatly help us if you could test that. Since you are the one spotting this bug, you can judge best if all scenarios are fixed :)

See I read it wrong now, sorry about that. Is there also an issue for the single selection mode? It seems to be working fine, at least with the changes in this code :)

[tnt-lrt]

Hi guys,

the behavior of the class ItemComparer, introduced in this fix is non-determenistic. For example when just valueA is implementing IComparable and valueB is not it might throw an exception. If you swap both values it will return false.