Bug 43710 - ListView's GroupHeaderTemplate do not work with DataTemplateSelector on Android
Summary: ListView's GroupHeaderTemplate do not work with DataTemplateSelector on Android
Alias: None
Product: Forms
Classification: Xamarin
Component: Forms ()
Version: 2.3.1
Hardware: PC Windows
: --- normal
Target Milestone: ---
Assignee: Bugzilla
Depends on:
Reported: 2016-08-24 17:35 UTC by Rodrigo Elias
Modified: 2017-09-28 10:33 UTC (History)
6 users (show)

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

Sample project with StackTrace in a txt file (197.64 KB, application/x-zip-compressed)
2016-08-24 17:35 UTC, Rodrigo Elias

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Description Rodrigo Elias 2016-08-24 17:35:40 UTC
Created attachment 17195 [details]
Sample project with StackTrace in a txt file

ListView's GroupHeaderTemplate do not work with DataTemplateSelector on Android (Xamarin.Forms The application crashes.
Works fine on iOS. 
Not tested on Windows Phone.

Sample project attached.

StackTrace.txt is inside the Sample Project's zip file.
Comment 1 Shane S. Anderson 2017-06-27 23:02:25 UTC
The error seems to be in ListViewAdapter.GetItemViewType():
    if (_listView.IsGroupingEnabled)
        item = TemplatedItemsView.TemplatedItems.GetGroup(group).ListProxy[row];
        item = TemplatedItemsView.TemplatedItems.ListProxy[position];

This second line is getting the first item within the group, rather than the group object itself.

See https://github.com/xamarin/Xamarin.Forms/blob/ec5492cd0da754bb372961a30170b7d3ce165ac2/Xamarin.Forms.Platform.Android/Renderers/ListViewAdapter.cs#L168.
Comment 2 Vincent Hoogendoorn 2017-09-28 10:33:19 UTC
Bug still exists in Xamarin Forms stable Bump: fix