Bug 43154 - Clearing CarouselPage ItemSource creates phantom item
Summary: Clearing CarouselPage ItemSource creates phantom item
Alias: None
Product: Forms
Classification: Xamarin
Component: Windows ()
Version: 2.3.1
Hardware: PC Windows
: Normal major
Target Milestone: ---
Assignee: Bugzilla
Depends on:
Reported: 2016-08-07 19:02 UTC by fiyahuluw
Modified: 2016-08-10 00:06 UTC (History)
3 users (show)

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

Scrolling past the last item in android emulator (179.67 KB, image/png)
2016-08-07 19:02 UTC, fiyahuluw

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Description fiyahuluw 2016-08-07 19:02:22 UTC
Created attachment 16936 [details]
Scrolling past the last item in android emulator

Clearing CarouselPage ItemSource then adding items causes a 'phantom' item to appear at the end of the CarouselPage that crashes the application when navigated to.

I encountered this bug on android and have not tested it on any other platforms.

Steps to reproduce:

1. Bind the ItemSource of a CarouselPage to an ObservableCollection<T>.

2. Be sure to populate the collection with at least one item before it is rendered to prevent a no items exception.

Within the same method:

3. Clear the collection with ObservableCollection<T>.Clear().

4. Populate the collection with new items.

Getting the error:

5. Scroll through the carousel until you get to the last real item. If you scroll just a bit further you will notice an extra empty page (the phantom item). Should you release the CarouselPage over this item it will attempt to select it and crash.
Comment 1 fiyahuluw 2016-08-07 19:37:58 UTC

The author of this thread appears to be having the same issue and has found a workaround: https://forums.xamarin.com/discussion/67490/xamarin-carousel-page-throws-system-argumentoutofrangeexception-on-last-page-swipe-only-on-android