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Created attachment 6721 [details]
I get the following exception after updating to iOS 188.8.131.52
The object was used after being disposed.
at MonoTouch.Foundation.NSObject.get_SuperHandle () [0x00015] in /Developer/MonoTouch/Source/maccore/src/Foundation/NSObject2.cs:328
at MonoTouch.UIKit.UIControl.set_Enabled (Boolean value) [0x0002b] in /Developer/MonoTouch/Source/monotouch/src/build/compat/UIKit/UIControl.g.cs:323
at SampleProj.Sample.ToggleManualMode (System.Object sender, System.EventArgs e) [0x0001a] in /Users/John/Downloads/SampleProj/SampleProj/Sample.cs:45
Steps to Reproduce:
1. Run the attached sample
2. Touch the UISwitch to "Enable the button".
Exception is thrown.
User who reported this issue did not notice the same exception on previous version of Xamarin.iOS using the same code.
> User who reported this issue did not notice the same exception on previous
> version of Xamarin.iOS using the same code.
That's correct. This check was added recently, i.e. it was not in older version of XI. The older XI could call a *_msgSendSuper_* with an invalid "SuperHandle" if the object was disposed.
What would happen at runtime is undefined (could be ignored, it could corrupt state/memory or it could crash) depending on the code being called. IOW nothing XI could do about - except avoid calling the code with an invalid handle (which is what we now do).
The new check/exception makes it clear where (and when) it happens. That nice because any corruption could go unnoticed for quite some time and cause random failures later, which makes debugging such bugs very hard.
OTOH it's possible that a "ignored" call (or unnoticed corruption) will make "working" code throw such an exception. In such case the (user) code needs to be fixed.
I cannot duplicate the issue with the attached sample. Not with the provided instructions (should be very simple), not with trying other things.
We have not received the requested information. If you are still experiencing this issue please provide all the requested information and re-open the bug report. Thanks!