EXC_BAD_ACCESS (SIGABRT) on MvvmCross

Question

MvvmCross_Core_MvvmCross_Core_ViewModels_MvxViewModelLoader_FindViewModelLocator_ causes app to crash. Looked through the MVVMCross source code and could not tell what caused this error and how to handle it. Appreciate any help here. Below is the crash report Using MMVMCross 4.0

<package id="MvvmCross.Core" version="4.0.0" targetFramework="xamarinios10" />



Incident Identifier: 73492D3A-04AC-4CB2-A30F-11C03932B333
CrashReporter Key:   89c9f505981a4f47ba51b95e37591830d9aeef45
Hardware Model:      iPhone6,1
Code Type:           ARM-64 (Native)
Parent Process:      launchd [1]

Date/Time:           2016-04-12 09:40:49.49 -0400
Launch Time:         2016-04-12 09:40:45.45 -0400
OS Version:          iOS 9.3.1 (13E238)
Report Version:      105

Exception Type:  EXC_BAD_ACCESS (SIGABRT)
Exception Subtype: KERN_INVALID_ADDRESS at 0x0000000000000000
Triggered by Thread:  0

Filtered syslog:
None found

Thread 0 name:  Dispatch queue: com.apple.main-thread
Thread 0 Crashed:
0   libsystem_kernel.dylib          0x0000000182c9c11c __pthread_kill + 8
1   libsystem_pthread.dylib         0x0000000182d68ef8 pthread_kill + 112
2   libsystem_c.dylib               0x0000000182c0ddac abort + 140
3   MobilityiOS                         0x0000000101630678 print_exception(MonoObject*, bool, NSMutableString*) (runtime.m:782)
4   MobilityiOS                         0x0000000101538220 mono_invoke_unhandled_exception_hook (mini-exceptions.c:2586)
5   MobilityiOS                         0x0000000101537694 mono_handle_exception_internal (mini-exceptions.c:1573)
6   MobilityiOS                         0x0000000101536604 mono_handle_exception (mini-exceptions.c:1799)
7   MobilityiOS                         0x000000010152f8bc mono_arm_throw_exception (exceptions-arm64.c:383)
8   MobilityiOS                         0x000000010051c278 throw_exception + 168
9   MobilityiOS                         0x0000000100f07e4c MvvmCross_Core_MvvmCross_Core_ViewModels_MvxViewModelLoader_FindViewModelLocator_MvvmCross_Core_ViewModels_MvxViewModelRequest + 0
10  MobilityiOS                         0x0000000100f07d00 MvvmCross_Core_MvvmCross_Core_ViewModels_MvxViewModelLoader_LoadViewModel_MvvmCross_Core_ViewModels_MvxViewModelRequest_MvvmCross_Core_ViewModels_IMvxBundle + 108
11  MobilityiOS                         0x00000001010b404c MvvmCross_iOS_MvvmCross_iOS_Views_MvxViewControllerExtensionMethods_LoadViewModel_MvvmCross_iOS_Views_IMvxIosView + 276
12  MobilityiOS                         0x0000000100f02474 MvvmCross_Core_MvvmCross_Core_Views_MvxViewExtensionMethods_OnViewCreate_MvvmCross_Core_Views_IMvxView_System_Func_1_MvvmCross_Core_ViewModels_IMvxViewModel + 96
13  MobilityiOS                         0x00000001010b3f28 MvvmCross_iOS_MvvmCross_iOS_Views_MvxViewControllerExtensionMethods_OnViewCreate_MvvmCross_iOS_Views_IMvxIosView + 100
14  MobilityiOS                         0x00000001010b2ff4 MvvmCross_iOS_MvvmCross_iOS_Views_MvxViewControllerAdapter_HandleViewDidLoadCalled_object_System_EventArgs + 136
15  MobilityiOS                         0x000000010042d0d4 mscorlib_wrapper_delegate_invoke__Module_invoke_void_object_EventArgs_object_System_EventArgs + 120
16  MobilityiOS                         0x0000000100edd43c MvvmCross_Platform_MvvmCross_Platform_Core_MvxDelegateExtensionMethods_Raise_System_EventHandler_object + 36
17  MobilityiOS                         0x0000000100f9bba4 MvvmCross_Platform_iOS_MvvmCross_Platform_iOS_Views_MvxEventSourceViewController_ViewDidLoad + 32
18  MobilityiOS                         0x000000010018b7a4 MobilityiOS_Mobility_iOS_Views_BaseMvxViewController_ViewDidLoad + 972
19  MobilityiOS                         0x000000010018c758 MobilityiOS_Mobility_iOS_Views_Main_HomeView_ViewDidLoad + 232
20  MobilityiOS                         0x00000001004ff784 wrapper_runtime_invoke_object_runtime_invoke_dynamic_intptr_intptr_intptr_intptr + 244
21  MobilityiOS                         0x00000001015430dc mono_jit_runtime_invoke (mini-runtime.c:2335)
22  MobilityiOS                         0x00000001015aa59c mono_runtime_invoke (object.c:2783)
23  MobilityiOS                         0x0000000101262d64 native_to_managed_trampoline_3(objc_object*, objc_selector*, _MonoMethod**, char const*, char const*) (registrar.m:118)
24  MobilityiOS                         0x0000000101266400 -[HomeView viewDidLoad] (registrar.m:3608)
25  UIKit                           0x000000018824cb40 -[UIViewController loadViewIfRequired] + 996
26  UIKit                           0x000000018830d118 -[UINavigationController _layoutViewController:] + 72
27  UIKit                           0x000000018830cff0 -[UINavigationController _updateScrollViewFromViewController:toViewController:] + 416
28  UIKit                           0x000000018830c238 -[UINavigationController _startTransition:fromViewController:toViewController:] + 144
29  UIKit                           0x000000018830bddc -[UINavigationController _startDeferredTransitionIfNeeded:] + 868
30  UIKit                           0x000000018830ba04 -[UINavigationController __viewWillLayoutSubviews] + 60
31  UIKit                           0x000000018830b96c -[UILayoutContainerView layoutSubviews] + 208
32  UIKit                           0x00000001882480e4 -[UIView(CALayerDelegate) layoutSublayersOfLayer:] + 656
33  QuartzCore                      0x0000000185beea28 -[CALayer layoutSublayers] + 148
34  QuartzCore                      0x0000000185be9634 CA::Layer::layout_if_needed(CA::Transaction*) + 292
35  QuartzCore                      0x0000000185be94f4 CA::Layer::layout_and_display_if_needed(CA::Transaction*) + 32
36  QuartzCore                      0x0000000185be8b24 CA::Context::commit_transaction(CA::Transaction*) + 252
37  QuartzCore                      0x0000000185be886c CA::Transaction::commit() + 512
38  QuartzCore                      0x0000000185be1dd8 CA::Transaction::observer_callback(__CFRunLoopObserver*, unsigned long, void*) + 80
39  CoreFoundation                  0x00000001830b87b0 __CFRUNLOOP_IS_CALLING_OUT_TO_AN_OBSERVER_CALLBACK_FUNCTION__ + 32
40  CoreFoundation                  0x00000001830b6554 __CFRunLoopDoObservers + 372
41  CoreFoundation                  0x0000000182fe0d30 CFRunLoopRunSpecific + 416
42  UIKit                           0x00000001882bb834 -[UIApplication _run] + 460
43  UIKit                           0x00000001882b5f70 UIApplicationMain + 204
44  MobilityiOS                         0x00000001002897a4 wrapper_managed_to_native_UIKit_UIApplication_UIApplicationMain_int_string___intptr_intptr + 324
45  MobilityiOS                         0x000000010020ed74 Xamarin_iOS_UIKit_UIApplication_Main_string___string_string + 156
46  MobilityiOS                         0x00000001001830a0 MobilityiOS_Mobility_iOS_Application_Main_string__ + 24
47  MobilityiOS                         0x00000001004ff784 wrapper_runtime_invoke_object_runtime_invoke_dynamic_intptr_intptr_intptr_intptr + 244
48  MobilityiOS                         0x00000001015430dc mono_jit_runtime_invoke (mini-runtime.c:2335)
49  MobilityiOS                         0x00000001015aa59c mono_runtime_invoke (object.c:2783)
50  MobilityiOS                         0x00000001015aec90 mono_runtime_exec_main (object.c:4038)
51  MobilityiOS                         0x00000001016424ac xamarin_main (monotouch-main.m:404)
52  MobilityiOS                         0x000000010128e78c main (main.arm64.m:130)
53  libdyld.dylib                   0x0000000182b7e8b8 start + 4

Answer 1

You should have 2 views using the same viewmodel.

This is forbidden by mvvmcross by default, and will crash the view/viewmodel locator.