[MonoTouch] Object reference not set exception when calling UIView.Animate

[Sebastien Pouliot]

Hello,

This was reported in bug #3950, along with a reproducable test case,
and is now fixed.

The workaround is to avoid having a null parameter for the
`completion` parameter (it can be replaced with a empty method) so a
missing null check won't cause the exception you're hitting.

Regards,
Sebastien

[1] https://bugzilla.xamarin.com/show_bug.cgi?id=3950

On Sun, Mar 18, 2012 at 5:10 AM, DMennis <dmennis at gmail.com> wrote:
> I think its a problem with 5.2.9 release of MonoTouch from 3/16. I'm getting
> the same error as technohead but a different situation. I can reproduce this
> on an iPad 3rd gen (iOS 5.1) and iPhone 4S (iOS 5.01) and in the simulator
> for both iPad and iPhone. Rolf, check out the code from my buddy @Tron5000
> http://spinningtheweb.blogspot.com/2011/08/custom-animations-for.html here .
> From this code, you'll be able to reproduce the error we are seeing. My
> error below is when I'm moving between controllers with a *custom
> animation*.
>
> ----
>
> OSX 10.7.3
> XCode: 4.3.1
> Monotouch: 5.2.0 (released on 3/16)
> Mono: 2.10.8
> MonoDevelop: 2.8.6.5
>
> Message: Object reference not set to an instance of an object StackTrace:
> at MonoTouch.UIKit.UIView+<Transition>c__AnonStorey14.<>m__16 (Boolean x)
> [0x00000] in /Developer/MonoTouch/Source/monotouch/src/UIKit/UIView.cs:113
>  at MonoTouch.UIKit.UIView.TrampolineUICompletionHandler (IntPtr block,
> Boolean finished) [0x0004d] in
> /Developer/MonoTouch/Source/monotouch/src/UIKit/UIView.g.cs:1590
>  at (wrapper native-to-managed)
> MonoTouch.UIKit.UIView:TrampolineUICompletionHandler (intptr,int)
>  at (wrapper managed-to-native)
> MonoTouch.UIKit.UIApplication:UIApplicationMain (int,string[],intptr,intptr)
>  at MonoTouch.UIKit.UIApplication.Main (System.String[] args, System.String
> principalClassName, System.String delegateClassName) [0x00042] in
> /Developer/MonoTouch/Source/monotouch/src/UIKit/UIApplication.cs:29
>  at Shortlytics.Application.Main (System.String[] args) [0x00000] in
> /Users/dev/Desktop/iOSProjects/Shortlytics HD/ShortlyticsHD/Main.cs:12
>
> Let me know if I can provide any more details.
>
> Dennis H
> Hills Interactive
> @dmennis
>
> --
> View this message in context: http://monotouch.2284126.n4.nabble.com/Object-reference-not-set-exception-when-calling-UIView-Animate-tp4479639p4481844.html
> Sent from the MonoTouch mailing list archive at Nabble.com.
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