Bug 60337 - Null Reference Exception in LoadApplication in FormsAppCompatActivity (NRE) due to changes from #59882
Summary: Null Reference Exception in LoadApplication in FormsAppCompatActivity (NRE) d...
Alias: None
Product: Forms
Classification: Xamarin
Component: Android ()
Version: 2.4.0
Hardware: PC Windows
: --- normal
Target Milestone: ---
Assignee: Bugzilla
: 60346 ()
Depends on:
Reported: 2017-10-23 20:14 UTC by Almando
Modified: 2017-10-27 17:38 UTC (History)
5 users (show)

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

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Description Almando 2017-10-23 20:14:15 UTC
Exception on during LoadApplication() in FormsAppCompatActivity.cs due to the following recent code addition:

var iver = Platform.GetRenderer(application.MainPage); // Offending line.
if (iver != null)

Prior to 2.4.0 R2, Application.MainPage could be null until OnStart() was called and now causes NRE if not set during LoadApplication(new App(..));s.Platform.Android\AppCompat\FormsAppCompatActivity.cs:152
Comment 1 Chris King 2017-10-23 20:31:25 UTC
Sorry about that. https://github.com/xamarin/Xamarin.Forms/pull/1221
Comment 2 Almando 2017-10-23 20:32:44 UTC
Not Application
* MainPage
Comment 3 Almando 2017-10-23 20:38:16 UTC
The property MainPage in the Application class was able to be null prior to OnStart(). 

The NRE happens inside Platform.GetRenderer(..) when passed in a null 'MainPage'.
Comment 4 Paul DiPietro [MSFT] 2017-10-24 14:36:29 UTC
*** Bug 60346 has been marked as a duplicate of this bug. ***
Comment 5 RockStar 2017-10-24 17:43:26 UTC
I have this error after update to XF
Comment 6 Wallace Santos 2017-10-24 18:46:04 UTC
I have this bug (or something like as) in version (See Bug 60346 I submitted today).
Comment 7 Samantha Houts [MSFT] 2017-10-27 17:38:23 UTC
Should be fixed in 2.4.0 SR3. Thank you!