Bug 40513 - Adding views to CarouselView after rendered and swiping crashes Forms v.
Summary: Adding views to CarouselView after rendered and swiping crashes Forms v.
Alias: None
Product: Forms
Classification: Xamarin
Component: Forms ()
Version: 2.2.0
Hardware: PC Windows
: --- normal
Target Milestone: ---
Assignee: Bugzilla
Depends on:
Reported: 2016-04-19 09:27 UTC by FieldstrikeMobile
Modified: 2016-06-02 07:40 UTC (History)
3 users (show)

Is this bug a regression?: ---
Last known good build:

Repo Case (321.43 KB, application/zip)
2016-04-19 09:27 UTC, FieldstrikeMobile

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Description FieldstrikeMobile 2016-04-19 09:27:15 UTC
Created attachment 15763 [details]
Repo Case

I have attached a small sample. ( I have only tested on Android so far)

The sample contains a carouselview with 10 views and a button at the top which adds pages to the start of the observable collection like so:

    Items.Insert(0, string.Format("New page {0}", i));

Steps to reproduce this bug.

1. Start the application.
2. Click the "Add Page" button 3 times
3. Swipe to the left twice (so that you end up on the "string 2" page)
4. crash.


04-19 10:21:53.212 I/MonoDroid(16090): UNHANDLED EXCEPTION:
04-19 10:21:53.217 I/MonoDroid(16090): System.InvalidOperationException: Sequence contains more than one element
04-19 10:21:53.217 I/MonoDroid(16090):   at System.Linq.Enumerable.Single[TSource] (IEnumerable`1 source) [0x0008e] in /Users/builder/data/lanes/3053/a94a03b5/source/mono/external/referencesource/System.Core/System/Linq/Enumerable.cs:1050 
04-19 10:21:53.217 I/MonoDroid(16090):   at Xamarin.Forms.Platform.Android.CarouselViewRenderer+<>c__DisplayClass8_0.<Initialize>b__5 (Int32 disappearingPosition) [0x00021] in C:\BuildAgent3\work\aad494dc9bc9783\Xamarin.Forms.Platform.Android\Renderers\CarouselViewRenderer.cs:493 
04-19 10:21:53.217 I/MonoDroid(16090):   at Xamarin.Forms.Platform.Android.PhysicalLayoutManager.OnAppearingOrDisappearing (Int32 position, Boolean isAppearing) [0x0004b] in C:\BuildAgent3\work\aad494dc9bc9783\Xamarin.Forms.Platform.Android\Renderers\CarouselViewRenderer.cs:842 
04-19 10:21:53.217 I/MonoDroid(16090):   at Xamarin.Forms.Platform.Android.PhysicalLayoutManager.OnLayoutChildren (Android.Support.V7.Widget.Recycler recycler, Android.Support.V7.Widget.State state) [0x000ef] in C:\BuildAgent3\work\aad494dc9bc9783\Xamarin.Forms.Platform.Android\Renderers\CarouselViewRenderer.cs:1073 
04-19 10:21:53.217 I/MonoDroid(16090):   at Xamarin.Forms.Platform.Android.PhysicalLayoutManager.ScrollBy (Xamarin.Forms.Platform.Android.IntVector& delta, Android.Support.V7.Widget.Recycler recycler, Android.Support.V7.Widget.State state) [0x0007d] in C:\BuildAgent3\work\aad494dc9bc9783\Xamarin.Forms.Platform.Android\Renderers\CarouselViewRenderer.cs:825 
04-19 10:21:53.217 I/MonoDroid(16090):   at Xamarin.Forms.Platform.Android.PhysicalLayoutManager.ScrollHorizontallyBy (Int32 dx, Android.Support.V7.Widget.Recycler recycler, Android.Support.V7.Widget.State state) [0x00009] in C:\BuildAgent3\work\aad494dc9bc9783\Xamarin.Forms.Platform.Android\Renderers\CarouselViewRenderer.cs:1128 
04-19 10:21:53.217 I/MonoDroid(16090):   at Android.Support.V7.Widget.RecyclerView+LayoutManager.n_ScrollHorizontallyBy_ILandroid_support_v7_widget_RecyclerView_Recycler_Landroid_support_v7_widget_RecyclerView_State_ (IntPtr jnienv, IntPtr native__this, Int32 dx, IntPtr native_recycler, IntPtr native_state) [0x0001a] in <filename unknown>:0 
04-19 10:21:53.217 I/MonoDroid(16090):   at (wrapper dynamic-method) System.Object:23377f6f-6d85-4994-8b7b-6e969eb10f4a (intptr,intptr,int,intptr,intptr)
Comment 1 Chris King 2016-06-01 23:40:48 UTC
Android reported scroll idle when actually settling.
Comment 2 FieldstrikeMobile 2016-06-02 07:40:10 UTC
@ChrisKing which version of Xamarin Forms is this fixed for? so I can verify it has been fixed