[ViewPager2] Focus events causing ViewPager2 to unexpectedly the change page [140656866]

Fixed

Bug

Status Update

No update yet.

Description

ne...@gmail.com

created issue #1

Sep 8, 2019 06:50AM

It doesn't matter if the keyboard is being hidden from code (hideSoftInputFromWindow) or from user interface by hitting back button quickly enough while the page transition is in progress.

I've added the keyboard hiding to my previously used (another bug report) example

https://github.com/AlmightyCZ/ViewPager2TextInputGravity
To replicate the issue, switch to second page(FORM), focus the editText, leave the keyboard open and use the tab to switch to the third page(LAST). The ViewPager jumps to LAST page for a split second and then immediately back to FORM. If the keyboard is not showing, then the page changes happens without any problem.

Using View/Handler.post for hideKeyboard invocation doesn't change the outcome, only postDelayed with long enough delay "works".

Comments

je...@google.com <je...@google.com> #2Sep 13, 2019 11:02PM

Hi, thanks for reporting. Should be an easy fix!

I'm guessing it should work find until ~ 2^23 items = ~ 8M items. How did you come across this bug? Do you have a ViewPager2 with that many items?

je...@google.com <je...@google.com> #3Sep 17, 2019 02:27PM

Hi, good to hear that.

We have an implementation of RecyclerView.Adapter that supports "infinite looping". So when the infinite looping is enabled, the adapter's getItemCount() reports Int.MAX_VALUE items. We also call setCurrentItem to somewhere in the middle of item count on the ViewPager2, so that's how we got that far.

je...@google.com <je...@google.com> #4Sep 17, 2019 03:53PM

For future reference: first item for which it fails is probably when mCurrentItem = (1 << 25) + 2

je...@google.com <je...@google.com> #5Sep 17, 2019 05:00PM

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

commit 2e9f35536432bed0677171c8ae59b4f67850915a
Author: Jelle Fresen <jellefresen@google.com>
Date: Fri Jul 12 14:26:10 2019

Use double instead of float for decimal positions

A position ranges from 0 to Integer.MAX_VALUE, but floats only have a 23
bit mantissa. Values over 2^23 are rounded to a nearby value.

Solve this by using double instead of float when we need to represent a
position with a fractional component. A double has a mantissa of 52 bit
and can therefore represent all 2^32 possible int values.

Bug: 134858960
Test: ./gradlew viewpager2:cC
Change-Id: I08b97df6fac600caa83366ccab8671541e2c1e7f

A viewpager2/src/androidTest/java/androidx/viewpager2/test/ui/SparseAdapter.kt
M viewpager2/src/androidTest/java/androidx/viewpager2/widget/FakeDragTest.kt
M viewpager2/src/androidTest/java/androidx/viewpager2/widget/OffscreenPageLimitTest.kt
M viewpager2/src/androidTest/java/androidx/viewpager2/widget/PageChangeCallbackTest.kt
M viewpager2/src/androidTest/java/androidx/viewpager2/widget/PageTransformerTest.kt
M viewpager2/src/androidTest/java/androidx/viewpager2/widget/SetItemWhileScrollInProgressTest.kt
M viewpager2/src/main/java/androidx/viewpager2/widget/ScrollEventAdapter.java
M viewpager2/src/main/java/androidx/viewpager2/widget/ViewPager2.java

https://android-review.googlesource.com/1014538

https://goto.google.com/android-sha1/2e9f35536432bed0677171c8ae59b4f67850915a

ap...@google.com <ap...@google.com> #6Sep 19, 2019 06:47PM

Fixed in now released beta03 -

https://developer.android.com/jetpack/androidx/releases/viewpager2#1.0.0-beta03

jg...@google.com <jg...@google.com> Sep 20, 2019 01:41PM

Accepted by je...@google.com.

ap...@google.com <ap...@google.com> #7Sep 20, 2019 05:06PM

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

ap...@google.com <ap...@google.com> #8Sep 20, 2019 05:06PM

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

jg...@google.com <jg...@google.com> #9Sep 30, 2019 02:08PM

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

ti...@gmail.com <ti...@gmail.com> #10Oct 1, 2019 09:20AM

Any plan when the next release is?

jg...@google.com <jg...@google.com> #11Oct 2, 2019 01:46PM

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.

ti...@gmail.com <ti...@gmail.com> #12Oct 2, 2019 03:09PM

Thanks, that's somewhat useful.

an...@wpost.com <an...@wpost.com> #13Oct 10, 2019 12:35PM

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!

jg...@google.com <jg...@google.com> #14Oct 11, 2019 05:29PM

Marked as fixed.

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

pa...@google.com <pa...@google.com> #15Jul 5, 2022 10:40PM

This is still happening for me (see screencast) and seems to be caused by: https://android-review.googlesource.com/c/platform/frameworks/support/+/1126151

In our code, we have viewpager.setFocusability(false) but a child view is focusable. This combination causes the offending code to be called and the next item to show up briefly:

if (hasFocus()) { // if clear focus did not succeed
  mRecyclerView.requestFocus(View.FOCUS_FORWARD);
}

Reading the commit history it looks like the above code was added for API < 28. Is it possible to check for both hasFocus() && API < 28 here?

ap...@google.com <ap...@google.com> #16Dec 11, 2023 07:12PM

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