Bug 60608 - ListView BindingContext bound to the wrong Template
Summary: ListView BindingContext bound to the wrong Template
Status: CONFIRMED
Alias: None
Product: Forms
Classification: Xamarin
Component: Forms ()
Version: 2.5.0
Hardware: Macintosh Mac OS
: Normal major
Target Milestone: ---
Assignee: Bugzilla
URL:
Depends on:
Blocks:
 
Reported: 2017-11-10 02:26 UTC by Rein Vdst
Modified: 2017-11-10 04:26 UTC (History)
3 users (show)

Tags: listview, crash, bindingcontext, ac
Is this bug a regression?: ---
Last known good build:


Attachments
Repro Project (58.96 KB, application/zip)
2017-11-10 02:26 UTC, Rein Vdst
Details


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Status:
CONFIRMED

Description Rein Vdst 2017-11-10 02:26:19 UTC
Created attachment 25627 [details]
Repro Project

When using a DataTemplate Selector in Xamarin Forms (Android) the ViewCell BindingContext is sometimes set to the wrong Template.

If you look at  the Repro project I've added. Build it and click on an item to get the error.

Basicly:

ListView with a DataTemplate selector that has multiple templates (viewcells). Each of those cells use a grid to 'layout' the cell.

Those cells are getting a variable length of text (so that we force HasUnEvenRows to work).

In the repro project there are 4 templates, 1 that displays the name and 1 tag. The other 3 display the name and the first 3 tags.

Once you click on an item, a template that should display 3 tags gets it's BindingContext updated with an item that should receive the template that displays only 1 tag (as it has only 1 tag). Hence the error and you can see that the DataTemplateSelector or the mechanism behind it is Updating the bindingcontext of the wrong template.