Bug 24957 - Android/iOS ListView not Updating
Summary: Android/iOS ListView not Updating
Alias: None
Product: Forms
Classification: Xamarin
Component: Forms ()
Version: 1.3.0
Hardware: Other Other
: Normal normal
Target Milestone: ---
Assignee: Bugzilla
Depends on:
Reported: 2014-12-01 11:44 UTC by Andrew Page
Modified: 2016-03-25 18:46 UTC (History)
4 users (show)

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

Demonstration Project for android and ios (3.38 MB, application/x-bzip2)
2014-12-01 11:44 UTC, Andrew Page

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Description Andrew Page 2014-12-01 11:44:44 UTC
Created attachment 8922 [details]
Demonstration Project for android and ios

When updating a ListView via a ObservableCollection<T> the list view stops updating after two entries(Android) and doesn't update at all under ios.   There is a partial workaround by prepopulating the list with items, then clearing it, however after that the list will only update as many items as there were intitially.  Attached is a project that duplicates the issue.  

Curiously, if you uncomment the entry for 'countLabel' in the xaml file and is corresponding code in ListIssuePage the list starts updating as expected.  However, in the projects that this issue is being culled from adding/removing items from the view is NOT a reliable way of restoring this functionality.  

this is occurring in Xamarin Forms
Comment 1 Andrew Page 2014-12-01 12:26:52 UTC
Updating the form packages to 1.3.0-6275-pre1 did NOT provide any relief
Comment 2 Andrew Page 2014-12-01 12:28:58 UTC
In the case where you add a label and update it with the incoming event, which seems to make the ListView update as expected.  If you comment out the

countLabel.Text = String.Format("Count={0}", count); 

preventing the label from updating
the list doesn't update any more.
Comment 3 Parmendra Kumar 2014-12-05 10:14:29 UTC
I have checked this issue with attached sample project sample and I am getting different behavior with Android and iOS. 
Please check the screencast and let we know if you getting same behavior or I have missed anything.
Could you please provide environment info that can be helpful to reproduce at my end.

Screencast: http://www.screencast.com/t/Z8oOu8cxYolW

Environment info:

Xamarin Studio 5.5.4 (build 15)
Xamarin.Android : (Business Edition)
Xcode 6.1 (6602)
Xamarin.iOS : (Business Edition)
Xamarin.Mac (Business Edition)
Operating System Mac OS X 10.9.4
Comment 4 Jason Smith [MSFT] 2016-03-25 18:46:40 UTC
Thank you for taking the time to submit this report. After reviewing the description of this bug, we no longer believe it affects the current version of Xamarin.Forms. If you are still experiencing the issue after updating your packages, please reopen this report with an attached reproduction.
For your convenience, we have created some reproduction best practices viewable here: https://gist.github.com/jassmith/92405c300e54a01dcc6d

Warm regards,
Xamarin Forms Team