Bug 16799 - UIAlertDialog Crash with dynamic delegate
Summary: UIAlertDialog Crash with dynamic delegate
Status: RESOLVED INVALID
Alias: None
Product: iOS
Classification: Xamarin
Component: XI runtime ()
Version: 7.1.0.x
Hardware: PC Mac OS
: --- normal
Target Milestone: Untriaged
Assignee: Bugzilla
URL:
Depends on:
Blocks:
 
Reported: 2013-12-14 03:12 UTC by David Screve
Modified: 2013-12-16 08:56 UTC (History)
2 users (show)

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


Attachments
Problem example (8.88 KB, application/zip)
2013-12-14 03:12 UTC, David Screve
Details


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Status:
RESOLVED INVALID

Description David Screve 2013-12-14 03:12:04 UTC
Created attachment 5660 [details]
Problem example

If you use a dynamic Delegate with UIAlertDialog, application crash when user click on OK button.

Workaround : use delegate as member of the class.

See attached example : Clicking on "Click Me" and then "OK" work fine : Delegate is a member of the ViewController.

Then, click on "Crash me" and then "OK" : application crash because Delegate is dynamically created.
Comment 1 Rolf Bjarne Kvinge [MSFT] 2013-12-16 08:56:04 UTC
This is sort of expected - you must make sure managed objects aren't freed before native code is finished with them.

In the crashing example the managed GC does not know that native code is still using the UIAlertView, and will thus the UIAlertViewDelegate (which only the UIAlertView references). And when you click the button, UIAlertView will try to call the "Clicked" method on the freed UIAlertViewDelegate.