Bug 39847 - Using MasterDetailPage class as a ExportRenderer does not load in Android.
Summary: Using MasterDetailPage class as a ExportRenderer does not load in Android.
Alias: None
Product: Forms
Classification: Xamarin
Component: Android ()
Version: 2.1.0
Hardware: PC Windows
: --- normal
Target Milestone: ---
Assignee: Rui Marinho
: 38117 42818 ()
Depends on:
Reported: 2016-03-22 18:28 UTC by Jon Douglas [MSFT]
Modified: 2017-01-26 00:19 UTC (History)
5 users (show)

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

MasterDetailPage (6.85 MB, application/x-7z-compressed)
2016-03-22 18:28 UTC, Jon Douglas [MSFT]

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Description Jon Douglas [MSFT] 2016-03-22 18:28:27 UTC
Created attachment 15490 [details]


Using the ExportRenderer functionality with a MasterDetailPage inside Xamarin.Android does not seem to load unless there is a subclass created of the parent class (MasterDetailPage).

For example:

[assembly: ExportRenderer(typeof(MasterDetailPage), typeof(masterDetailPOC.Droid.NativeDroidMasterDetail))]

Does not work in Xamarin.Android, however the iOS equivalent will work:

[assembly: ExportRenderer(typeof(MasterDetailPage), typeof(masterDetailPOC.iOS.Custom.NativeiOSMasterDetail), UIUserInterfaceIdiom.Pad)]

However we can get this to work in Xamarin.Android if we create a subclass of MasterDetailPage and then refer to that type instead:

[assembly: ExportRenderer(typeof(masterDetailPOC.mstDetail), typeof(masterDetailPOC.Droid.NativeDroidMasterDetail))] 


See the following reproduction attachment. You can open up the solution and run the Xamarin.Android project.

You will see the following definition in the NativeDroidMasterDetail.cs file. Notice that putting a breakpoint/etc in the NativeDroidMasterDetail.cs file will not be hit.

//[assembly: ExportRenderer(typeof(masterDetailPOC.mstDetail), typeof(masterDetailPOC.Droid.NativeDroidMasterDetail))] 
[assembly: ExportRenderer(typeof(MasterDetailPage), typeof(masterDetailPOC.Droid.NativeDroidMasterDetail))]

However if we swap these items:

[assembly: ExportRenderer(typeof(masterDetailPOC.mstDetail), typeof(masterDetailPOC.Droid.NativeDroidMasterDetail))] 
//[assembly: ExportRenderer(typeof(MasterDetailPage), typeof(masterDetailPOC.Droid.NativeDroidMasterDetail))]

Breakpoints are hit and the renderer are loaded just fine.

*Version Information:

Comment 1 Rui Marinho 2016-04-19 17:03:44 UTC
Should be fixed in 2.3
Comment 2 Parmendra Kumar 2016-05-02 17:38:51 UTC
I have checked this issue with Xamarin.Forms 2.3.0-pre2 and its working fine. 

Hence closing this issue.
Comment 3 E.Z. Hart [MSFT] 2017-01-26 00:19:01 UTC
*** Bug 38117 has been marked as a duplicate of this bug. ***
Comment 4 E.Z. Hart [MSFT] 2017-01-26 00:19:14 UTC
*** Bug 42818 has been marked as a duplicate of this bug. ***