Bug 8235 - UINavigationController gets unrecognized selector exception, NSConcreteHashtable, on iOS4.2 using MT6.0.4
Summary: UINavigationController gets unrecognized selector exception, NSConcreteHashta...
Status: RESOLVED DUPLICATE of bug 7742
Alias: None
Product: iOS
Classification: Xamarin
Component: XI runtime ()
Version: 6.0.x
Hardware: Macintosh Mac OS
: --- normal
Target Milestone: Untriaged
Assignee: Bugzilla
Depends on:
Reported: 2012-11-05 20:30 UTC by BillF
Modified: 2012-11-05 22:14 UTC (History)
2 users (show)

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

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Description BillF 2012-11-05 20:30:04 UTC
This could well be a duplicate of 7742, but in case ...

My app, built on MT 6.0.4, crashes on an iOS4.2 device as follows:

MonoTouch.Foundation.MonoTouchException: Objective-C exception thrown.  Name: NSInvalidArgumentException Reason: -[NSConcreteHashTable objectAtIndex:]: unrecognized selector sent to instance 0x16c9880
  at MonoTouch.Foundation.NSArray.ArrayFromHandle[UIViewController] (IntPtr handle) [0x00000] in <filename unknown>:0
  at MonoTouch.UIKit.UIViewController.get_ChildViewControllers () [0x0002b] in /Developer/MonoTouch/Source/monotouch/src/UIKit/UIViewController.g.cs:1746
  at MonoTouch.UIKit.UINavigationController.get_ViewControllers () [0x0004a] in /Developer/MonoTouch/Source/monotouch/src/UIKit/UINavigationController.g.cs:325
  at MonoTouch.UIKit.UINavigationController.SetViewControllers (MonoTouch.UIKit.UIViewController[] controllers, Boolean animated) [0x00061] in /Developer/MonoTouch/Source/monotouch/src/UIKit/UINavigationController.g.cs:253
  at StarTrack.TrackingNavigationController.ViewDidLoad () [0x00023] in /Users/bfulton/Projects/iTrack/StarTrack/UI_iPhone/Tracking/TrackingNavigationController.cs:22
  at MonoTouch.UIKit.UIApplication.Main (System.String[] args, System.String principalClassName, System.String delegateClassName) [0x0004c] in /Developer/MonoTouch/Source/monotouch/src/UIKit/UIApplication.cs:38
  at StarTrack.Application.Main (System.String[] args) [0x00000] in /Users/bfulton/Projects/iTrack/StarTrack/Main.cs:48

The code is:

public class TrackingNavigationController : UINavigationController
		private static TrackingEnquiryViewController enquiryController;
		private static UIViewController[] viewControllers;
		public override void ViewDidLoad()
			base.ViewDidLoad ();			
			enquiryController = new TrackingEnquiryViewController();
			viewControllers = new UIViewController[] {enquiryController};
			SetViewControllers(viewControllers, false);   <---- crashes here

This worked on iOS4.* with earlier versions of MT, and works on iOS6.
Comment 1 Sebastien Pouliot 2012-11-05 22:14:33 UTC
it's fixed in 6.0.5+ (beta)
MonoTouch 6.0.6 should be released (as stable) "real soon now"(tm)

*** This bug has been marked as a duplicate of bug 7742 ***