Bug 13724 - Creating Second Instance of Generic UIViewController throws error
Summary: Creating Second Instance of Generic UIViewController throws error
Status: RESOLVED DUPLICATE of bug 13518
Alias: None
Product: iOS
Classification: Xamarin
Component: General ()
Version: 6.4.0
Hardware: Macintosh Mac OS
: --- normal
Target Milestone: Untriaged
Assignee: Bugzilla
Depends on:
Reported: 2013-08-02 16:07 UTC by alex.rodriguez
Modified: 2013-08-02 21:25 UTC (History)
2 users (show)

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

Test Project demonstrating the issue (6.46 KB, application/zip)
2013-08-02 16:07 UTC, alex.rodriguez

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Description alex.rodriguez 2013-08-02 16:07:46 UTC
Created attachment 4528 [details]
Test Project demonstrating the issue

In Xamarin.iOS 6.4, I am no longer able to use generic subclasses of UIViewController more than once.  When I try to create another instance of the generic ViewController of a different type, I get the following error:

Unable to cast object of type 'GenericsTest.SalesDocumentView' (Objective-C type: 'GenericsTest.SalesDocumentView') to type 'GenericsTest.CustomView`1[GenericsTest.Customer]'.
Additional information:
	Selector: loadView
	Method: GenericsTest.CustomView`1<GenericsTest.Customer>:LoadView ()

I've attached an example project which demonstrates my issue.  I push and instance of CustomerViewController onto the navigation stack, then tap a button on that view to push an instance of SalesDocumentViewController.  The error is thrown when the SalesDocumentViewController is created.

Both CustomerViewController and SalesDocumentViewController inherit from CustomView<T> (which inherits from UIViewController), themselves being CustomView<Customer> and CustomView<SalesDocument>.

This error only occurs on devices.  I've tried turning off "Enable Generic Value Type Sharing", if that matters.

Is this intended?  This sort of structure worked in prior versions.

Thank you.
Comment 1 Rolf Bjarne Kvinge [MSFT] 2013-08-02 21:25:18 UTC

*** This bug has been marked as a duplicate of bug 13518 ***