Bug 13897 - Exception is raised on attempt to navigate some class in Assembly Browser
Summary: Exception is raised on attempt to navigate some class in Assembly Browser
Alias: None
Product: Xamarin Studio
Classification: Desktop
Component: Assembly browser ()
Version: 4.0.12
Hardware: Macintosh Mac OS
: Normal normal
Target Milestone: master
Assignee: Mike Krüger
Depends on:
Reported: 2013-08-09 16:57 UTC by Ievgen
Modified: 2014-09-01 00:43 UTC (History)
4 users (show)

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

Notice (2018-05-24): bugzilla.xamarin.com is now in read-only mode.

Please join us on Visual Studio Developer Community and in the Xamarin and Mono organizations on GitHub to continue tracking issues. Bugzilla will remain available for reference in read-only mode. We will continue to work on open Bugzilla bugs, copy them to the new locations as needed for follow-up, and add the new items under Related Links.

Our sincere thanks to everyone who has contributed on this bug tracker over the years. Thanks also for your understanding as we make these adjustments and improvements for the future.

Please create a new report on Developer Community or GitHub with your current version information, steps to reproduce, and relevant error messages or log files if you are hitting an issue that looks similar to this resolved bug and you do not yet see a matching new report.

Related Links:

Description Ievgen 2013-08-09 16:57:10 UTC
I have an iOS project that refers MvvmCross assemblies. Sometimes when I try to navigate any class from MvvmCross framework I am getting an exception. The log says:

WARNING [2013-08-09 13:47:28Z]: Assembly browser: Can't find assembly: mscorlib, Version=, Culture=neutral, PublicKeyToken=7cec85d7bea7798e.
WARNING [2013-08-09 13:47:28Z]: Assembly browser: Can't find assembly: monotouch, Version=, Culture=neutral, PublicKeyToken=84e04ff9cfb79065.
ERROR [2013-08-09 13:47:28Z]: An unhandled exception has occured. Terminating MonoDevelop? False
System.AggregateException: One or more errors occured

I made several investigations, and it looks like the exception is raised only when I try to navigate MvxImageViewLoader class from MvvmCross, most other classes are navigated fine.

The same exception is raised when I try to navigate any extension method defined in MvvmCross.

I hope it helps.
Comment 1 Mike Krüger 2013-08-13 02:30:02 UTC
I've problems reproducing the issue - I've tried the binaries from: 


Can you give me the MvvmCross assembly that produces the crash ?
Comment 2 Ievgen 2013-09-07 18:01:29 UTC
Try to navigate to any extension method. For example:

using Cirrious.MvvmCross.Binding.BindingContext;
using Cirrious.MvvmCross.Binding.Touch.Views;

namespace Test
    public partial class HomeView : MvxViewController
        public HomeView()
            var set = this.CreateBindingSet<HomeView, HomeViewModel>();\

If you navigate this.CreateBindingSet(), you'll see "An error occurred dialog" with "System.AggregateException: One or more errors occured" inside.
Comment 3 Ievgen 2013-09-07 18:03:02 UTC
There will be one more namespace in mentioned example:

using Cirrious.MvvmCross.Touch.Views;

Sorry, I missed it.
Comment 4 Zack Gramana 2013-11-12 14:45:20 UTC
I just encountered this issue when trying to navigate, via CMD+D, to the ViewGroup type in Mono.Android.

=== Xamarin Studio ===

Version 4.0.13 (build 38)
Installation UUID: 47f03afd-7c04-4aec-8195-1b1617231ab4
	Mono 3.2.4 ((no/294f999)
	GTK+ 2.24.20 theme: Raleigh
	GTK# (
	Package version: 302040000

=== Xamarin.Android ===

Version: 4.10.1 (Business Edition)
Android SDK: /Users/zgramana/Library/Developer/Xamarin/android-sdk-mac_x86
	Supported Android versions:
		2.1   (API level 7)
		2.2   (API level 8)
		2.3   (API level 10)
		3.1   (API level 12)
		4.0   (API level 14)
		4.0.3 (API level 15)
		4.1   (API level 16)
		4.2   (API level 17)
		4.3   (API level 18)
Java SDK: /usr
java version "1.6.0_65"
Java(TM) SE Runtime Environment (build 1.6.0_65-b14-462-11M4609)
Java HotSpot(TM) 64-Bit Server VM (build 20.65-b04-462, mixed mode)

=== Apple Developer Tools ===

Xcode 5.0.1 (3335.23)
Build 5A2053

=== Xamarin.Mac ===

Xamarin.Mac: 1.6.19

=== Xamarin.iOS ===

Version: (Business Edition)
Hash: 23a0827
Build date: 2013-11-11 16:04:00-0500

=== Build Information ===

Release ID: 400130038
Git revision: 07afec667f7be5d0ee511eb7115bbac6377fbae8
Build date: 2013-09-24 08:53:29+0000
Xamarin addins: 61140345a5b109633a94409edcbc7a4c19a425c6

=== Operating System ===

Mac OS X 10.9.0
Darwin Zacharys-MacBook-Pro.local 13.0.0 Darwin Kernel Version 13.0.0
    Thu Sep 19 22:22:27 PDT 2013
    root:xnu-2422.1.72~6/RELEASE_X86_64 x86_64
Comment 5 Zack Gramana 2013-11-12 14:47:21 UTC
In my case, I only observe is the AggregateException. The Assembly Browser opens, and Mono.Android is visible in the assembly list. However, the detail pane displays the root view of the Mono.Android assembly.
Comment 6 Mike Krüger 2013-11-12 14:49:20 UTC
Should be fixed in 4.2
Comment 7 Mikayla Hutchinson [MSFT] 2013-11-12 15:47:10 UTC
I just saw this in 4.2.
Comment 8 Tom Gilder 2014-08-18 15:35:02 UTC
I am seeing this almost constantly in 5.3... and it's driving me a bit mad!

Just about every time I use "Go to Declaration" on a symbol that takes me to the Assembly Browser, I get an System.AggregateException; unless the Assembly Browser is already open, then it's fine.
Comment 9 Mike Krüger 2014-08-19 00:58:25 UTC
That regressed - but is fixed in master.
Comment 10 Ievgen 2014-08-22 14:20:16 UTC
Well, yeah maybe it's regression but in the last Xamarin Studio 5.2.1 (build 1) which is STABLE opening ANY library class definition in the Assembly Browser doesn't work. It just shows the old-good dialog with "System.AggregateException: One or more errors occured".

Isn't this a blocker?
Comment 11 Miha Valencic 2014-08-29 08:00:20 UTC
I confirm what Ievgen says. Mac OS X, Xamarin Studio 5.2.1 (build 1), does not work with MonoTouch objects (AggregateException). I can manually navigate to monotouch.MonoTouch.UiKit.UiView class though.

Any info on when this might come to stable release? Because the alpha channel is so buggy it does not even open the solution and projects.
Comment 12 Mike Krüger 2014-09-01 00:43:31 UTC
There is an easy work around:

Ignore the exception and navigate a 2nd time to the class - it should work..
No it's no blocker - it's not causing data loss and there is a simple work around.

I don't know when it'll land in stable - it's up to our QA process. We try to get out monthly releases.