Bug 28883 - Setting GroupDisplayBinding after GroupHeaderTemplate removes custom header template
Summary: Setting GroupDisplayBinding after GroupHeaderTemplate removes custom header t...
Status: RESOLVED INVALID
Alias: None
Product: Forms
Classification: Xamarin
Component: Forms ()
Version: 1.4.1
Hardware: PC Windows
: --- enhancement
Target Milestone: ---
Assignee: Bugzilla
URL:
Depends on:
Blocks:
 
Reported: 2015-04-08 08:44 UTC by Mitch Milam
Modified: 2016-04-08 19:37 UTC (History)
4 users (show)

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

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Status:
RESOLVED INVALID

Description Mitch Milam 2015-04-08 08:44:28 UTC
The documentation clearly states the following:

GroupHeaderTemplate is mutually exclusive with ListView.GroupDisplayBinding. Setting this property will set ListView.GroupDisplayBinding to null. 

And if you have the following code:

list.GroupDisplayBinding = new Binding("Key");
list.GroupHeaderTemplate = new DataTemplate(typeof (HeaderCell));

It works exactly as you specified.

The issue is if you have set these properties in this order:

list.GroupHeaderTemplate = new DataTemplate(typeof (HeaderCell));
list.GroupDisplayBinding = new Binding("Key");

Setting the GroupDisplayBinding after the GroupHeaderTemplate is defined will remove the custom header template.

This effects both iOS and Android. 


This can be a very simple mistake to make. So I think either:

1. The documentation needs to be updated and the above information added.
2. When the GroupDisplayBinding is set, if the GroupHeaderTemplate is not null, then the set GroupDisplayBinding  operation is ignored.

** Sample code and screen shots attached.
Comment 1 Mitch Milam 2015-04-08 08:58:19 UTC
Actually, the documentation does indeed state the obvious:
http://iosapi.xamarin.com/?link=P%3aXamarin.Forms.ListView.GroupDisplayBinding

This property is mutually exclusive with ListView.GroupHeaderTemplate property. Setting it will set ListView.GroupHeaderTemplate to null. 

But it would be really helpful to have those statements combined onto a single page.