Fixed
Status Update
No update yet.
Comments
jb...@google.com
Nested scrolling works partially (as per http://b/122818889 ). Let's discuss if we need full support and if so make sure it works.
ja...@icloud.com
Hi!
What is 'partially' exactly?
How do I see it?
Thanks!
What is 'partially' exactly?
How do I see it?
Thanks!
jb...@google.com
As of now:
- Nesting scroll views with a scroll direction perpendicular to the ViewPager2's orientation inside ViewPager2 works
- Nesting scroll views with a scroll direction parallel to the ViewPager2's orientation inside ViewPager2 does not work
- Nesting scroll views with a scroll direction perpendicular to the ViewPager2's orientation inside ViewPager2 works
- Nesting scroll views with a scroll direction parallel to the ViewPager2's orientation inside ViewPager2 does not work
ja...@icloud.com
Horizontal ViewPager2 not correctly working into a vertical RecyclerView
Set a setNestedScrollingEnabled to the RecyclerView into the ViewPager2 (across reflection) resolves the problem
Set a setNestedScrollingEnabled to the RecyclerView into the ViewPager2 (across reflection) resolves the problem
jb...@google.com
cl...@google.com
ageevvalentin@gmail.com, could you provide a sample app? I'd like to learn more about the circumstances that cause the problem; putting a clean ViewPager2 inside a clean RecyclerView seems to work fine, so there must be other factors involved.
ja...@icloud.com
Added a patch for androidx-master-dev that demos a horizontal ViewPager2 inside a vertical RecyclerView.
Verified that it works correctly on a:
- Nexus 4 emulator with API 17
- Nexus 5X emulator with API 28
- Pixel 2 device with API 29
To reproduce:
- Check out the Android Jetpack source (at commit 256899f482ff85cddfb050f37550be7b5ec927ef) (see steps in [1])
- Apply the patch (`git apply 0001-Add-sample-where-a-horizontal-ViewPager2-is-nested-i.patch`)
- Build and install viewpager2's integration-tests app: `./gradlew viewpager2:integration-tests:testapp:installDebug`
- Run it
Closing the issue for now, but please reopen if you have a minimal reproduction app
[1]https://android.googlesource.com/platform/frameworks/support/+/256899f482ff85cddfb050f37550be7b5ec927ef
Verified that it works correctly on a:
- Nexus 4 emulator with API 17
- Nexus 5X emulator with API 28
- Pixel 2 device with API 29
To reproduce:
- Check out the Android Jetpack source (at commit 256899f482ff85cddfb050f37550be7b5ec927ef) (see steps in [1])
- Apply the patch (`git apply 0001-Add-sample-where-a-horizontal-ViewPager2-is-nested-i.patch`)
- Build and install viewpager2's integration-tests app: `./gradlew viewpager2:integration-tests:testapp:installDebug`
- Run it
Closing the issue for now, but please reopen if you have a minimal reproduction app
[1]
ap...@google.com
Re-opening as requested by a few users. Narrowed down the focus to nested scrolling elements with the same scroll direction.
cl...@google.com
Any progress on this? (only talking about the "same scroll direction" issue)
I searched a lot for workarounds on Google and SO, but it seems no one really found a suitable solution yet.
The thing is that all other VerticalViewPagers out there have other problems that are similarly annoying. Most of them revolve around touch issues like "What's a click and what's a swipe" or "what's the fling threshold to snap to the next page".
So if someone knows of a working sample of VerticalViewPagers, I'd be happy to see a link :)
I searched a lot for workarounds on Google and SO, but it seems no one really found a suitable solution yet.
The thing is that all other VerticalViewPagers out there have other problems that are similarly annoying. Most of them revolve around touch issues like "What's a click and what's a swipe" or "what's the fling threshold to snap to the next page".
So if someone knows of a working sample of VerticalViewPagers, I'd be happy to see a link :)
il...@google.com
na...@google.com
Hi, we're unlikely to address the "same scroll direction" issue before 1.0-Stable as it's likely going to require API changes (so v1.1+).
One possible option for VerticalViewPager with nested scrolling in the same scroll direction is using a RecyclerView implementing NestedScrollingParent + PagerSnapHelper to get snapping.
You'd then have to implement the NestedScrollingParent/Child contract between parent/child RecyclerView instances.
One possible option for VerticalViewPager with nested scrolling in the same scroll direction is using a RecyclerView implementing NestedScrollingParent + PagerSnapHelper to get snapping.
You'd then have to implement the NestedScrollingParent/Child contract between parent/child RecyclerView instances.
Description
Version used: 2.5.3
Devices/Android versions reproduced on: Any
When popping the back stack with saveState=true, destinations are only added to backStackMap if they are not already present (courtesy of the takeWhile operations in popBackStackInternal). The savedState array is subsequently added to backStackStates regardless. In the case that no destinations are added to backStackMap, the savedState array subsequently becomes unreachable/unrestorable, as there is no reference to the back stack name/uuid key anywhere.
To reproduce the issue:
(1) Launch the NavigationAdvancedSample app in debug mode
(2) Repeat the following several times:
(a) Tap the "About" button to navigate to the about screen
(b) Tap the "Leaderboard" bottom navigation item to navigate to the leaderboard screen
(b) Tap the back button or swipe back to navigate to the title screen again
(3) After several repeats, inspect the navController's backStackStates (which will be sizeable) and backStackMap (the values of which will not contain most of backStackStates' keys, rendering them indefinitely unreachable in restoreStateInternal
Potential fix:
Make "backStackStates[firstState.id] = savedState" conditional on at least one addition to backStackMap