IssueTracker

> The Transition Kotlin extensions target the Framework Transition class which is a bit confusing

All extensions in 'core-ktx' target either 'core' or the framework types. This is working as expected. It sounds like this is a feature request for a transition-ktx with equivalent extensions for the androidx.transition types.

> as most framework classes are being deprecated in favor of their AndroidX counterparts, Fragments for example.

"Most"? This *dramatically* overstates what is actually happening. Fragments (and loaders) were added to the framework in a time where the Android team did not have external libraries for shipping features. Transition was added 5 years later.

Pardon my misunderstanding, I was under the belief that where possible, new features that could be developed outside the framework, would be under Androidx. Also it's a common refrain to use the Androidx libraries over the framework libraries where possible, as those ship update independently of platform releases. I wasn't attempting to be dramatic.

If the Transition api is unlikely to change, there is no need for a transition-ktx for androidx.transition types. If developers should use Androidx transitions over framework transitions where possible however, then it would be much appreciated.

I am well aware of the limitations that existed when Fragments and Loaders were created, and when the Transition api was introduced.

Project: platform/frameworks/support
Branch: androidx-master-dev

commit ae42e311ecfbac18cedc90e489d1fdde956a4557
Author: Jake Wharton <jakew@google.com>
Date:   Fri Nov 22 11:13:30 2019

    Introduce transition-ktx for standalone transition library
   
    These extensions are the same as androidx.core.transition for the platform types, just adapted to the standalone library.
   
    Bug: 138870873
    Test: gw :transition:transition-ktx:build :transition:transition-ktx:connectedCheck
    Change-Id: Ie80022cc60ed1f482b7593db5ef1ac1c5ea33d8d

M       buildSrc/src/main/kotlin/androidx/build/PublishDocsRules.kt
M       jetifier/jetifier/migration.config
M       settings.gradle
A       transition/transition-ktx/OWNERS
A       transition/transition-ktx/api/1.4.0-alpha01.txt
A       transition/transition-ktx/api/current.txt
A       transition/transition-ktx/api/public_plus_experimental_1.4.0-alpha01.txt
A       transition/transition-ktx/api/public_plus_experimental_current.txt
A       transition/transition-ktx/api/res-1.4.0-alpha01.txt
A       transition/transition-ktx/api/restricted_1.4.0-alpha01.txt
A       transition/transition-ktx/api/restricted_current.txt
A       transition/transition-ktx/build.gradle
A       transition/transition-ktx/src/androidTest/AndroidManifest.xml
A       transition/transition-ktx/src/androidTest/java/androidx/transition/TestActivity.kt
A       transition/transition-ktx/src/androidTest/java/androidx/transition/TransitionTest.kt
A       transition/transition-ktx/src/androidTest/res/layout/test_activity.xml
A       transition/transition-ktx/src/main/AndroidManifest.xml
A       transition/transition-ktx/src/main/java/androidx/transition/Transition.kt

https://android-review.googlesource.com/1172715

Root cause:
After the keyboard is hidden, the focused TextView will ensure that it's cursor is visible on the screen, which leads to a call to requestChildRectangleOnScreen [1]. Since the EditText on the old page still has focus, ViewPager2 will initiate a scroll back to the old page.

Comparison with ViewPager:
Contrary to RecyclerView, ViewPager doesn't implement requestChildRectangleOnScreen() and the default implementation in ViewGroup does nothing.
Also, note that ViewPager transfers the focus to the new page during setCurrentItem [2].

Possible solutions:
1. Clear focus from old page and request focus on new page when updating mCurrentItem
2. Ignore calls to requestChildRectangleOnScreen like in ViewPager
3. Other..

I'm leaning towards solution 1.

[1] https://android.googlesource.com/platform/frameworks/support/+/bfc1455f551ff1caf2766b3755361905a791e538/viewpager2/src/main/java/androidx/viewpager2/widget/ViewPager2.java#1013
[2] https://android.googlesource.com/platform/frameworks/support/+/bfc1455f551ff1caf2766b3755361905a791e538/viewpager/src/main/java/androidx/viewpager/widget/ViewPager.java#1255

Project: platform/frameworks/support
Branch: androidx-master-dev

commit d4fa4242b0d945b8d3ff188602331b5124b3ace0
Author: Jakub Gielzak <jgielzak@google.com>
Date:   Thu Sep 19 15:50:24 2019

    Disabled requestChildRectangleOnScreen
   
    It was a source of issues. Disabling it is on par with what ViewPager1
    does. Users should use setCurrentItem instead.
   
    Bug: 140656866
    Test: EditTextFocusTest
   
    Change-Id: I63c5f05fbc72174d7af044b6c7c689833f56ae11

M       viewpager2/src/androidTest/java/androidx/viewpager2/widget/EditTextFocusTest.kt
M       viewpager2/src/main/java/androidx/viewpager2/widget/ViewPager2.java

https://android-review.googlesource.com/1125359
https://goto.google.com/android-sha1/d4fa4242b0d945b8d3ff188602331b5124b3ace0

Project: platform/frameworks/support
Branch: androidx-master-dev

commit f4ef0c4ea7c143931a166169ffdf499323f60842
Author: Jelle Fresen <jellefresen@google.com>
Date:   Fri Sep 20 16:44:31 2019

    Fix broken AccessibilityTest
   
    performAccessibilityAction should be called on the UI thread. For some
    reason it never surfaced before, presumably because the scrolling that
    it triggers was performed in onAnimation and not as a direct result of
    the action. Now we clear focus, however, this action triggers a change
    in the view and the test crashes.
   
    Bug: 140656866
    Test: ./gradlew recyclerview:recyclerview:cC \
            -Pandroid.testInstrumentationRunnerArguments.class=\
            androidx.viewpager2.widget.AccessibilityTest
   
    Change-Id: Ia7113fac1f9152ddaea4499a56220fea09822407

M       viewpager2/src/androidTest/java/androidx/viewpager2/widget/AccessibilityTest.kt

https://android-review.googlesource.com/1126614
https://goto.google.com/android-sha1/f4ef0c4ea7c143931a166169ffdf499323f60842

Project: platform/frameworks/support
Branch: androidx-master-dev

commit d9000ec31ab4743ed07c8aa713d506ea57c37de2
Author: Jelle Fresen <jellefresen@google.com>
Date:   Fri Sep 20 15:49:02 2019

    Clear focus on page change in ViewPager2
   
    Makes sure that a page can't keep focus when it is moving out of the
    screen.
   
    Bug: 140656866
    Test: follow-up
   
    Change-Id: I4e0fece0d4c438da76bfcb10939ba1bc880e27e7

M       viewpager2/src/main/java/androidx/viewpager2/widget/ViewPager2.java

https://android-review.googlesource.com/1126610
https://goto.google.com/android-sha1/d9000ec31ab4743ed07c8aa713d506ea57c37de2

Fixes are in place now. Will come out in the next release.

Any plan when the next release is?

We are aiming to release beta05 with the fix on October 9, but we are unable to make promises as it depends on other AndroidX libraries.

Thanks, that's somewhat useful.

It looks like this change has broken the ability to use DPAD_LEFT or DPAD_RIGHT navigation by setting items as focusable.

https://android-review.googlesource.com/c/platform/frameworks/support/+/1125359/

Is there a workaround? I can make a sample if needed, and perhaps a new issue. Thanks!

Fix for the original issue is now out (released on Oct 9 with beta05). Marking as Fixed.

Regarding comment#13 (DPAD_*) -- moving to http://issuetracker.google.com/142548536

Project: platform/frameworks/support
Branch: androidx-master-dev

commit 4e83b07b60706d954045f24b600338fae14abb2c
Author: Jakub Gielzak <jgielzak@google.com>
Date:   Mon Sep 23 19:53:57 2019

    Clear focus on page change on API < 28
   
    Follow-up to: I4e0fece0d4c438da76bfcb10939ba1bc880e27e7
   
    Bug: 140656866
    Test: follow-up
   
    Change-Id: I91bcd072e1812eeb20fbce6fb989557d60079bb7

M       viewpager2/src/main/java/androidx/viewpager2/widget/ViewPager2.java

https://android-review.googlesource.com/1126151