After first appearing on screen, the DataGrid will cause a NullReferenceException when navigating away. Also occurs if you have a DataGrid in a RadTabView and you switch to another tab.
Same code works on UWP, Android. Crashes on iOS.
XAML:
<tdg:RadDataGrid x:Name="grid"
ItemsSource="{Binding Parts}"
HorizontalOptions="FillAndExpand" VerticalOptions="FillAndExpand"
IsVisible="{Binding ShowData}"
StyleClass="TelerikTheme"
AlternateRowBackgroundStyle="{StaticResource DefaultDataGridAlternatingRowStyle}"
GroupHeaderStyle="{StaticResource DefaultDataGridGroupHeaderStyle}"
AutoGenerateColumns="False"
SelectionMode="None"
UserEditMode="None">
<tdg:RadDataGrid.Columns>
<tdg:DataGridTextColumn PropertyName="PrimaryId"
HeaderText="Primary ID"
CanUserFilter="False"
HeaderStyle="{StaticResource DefaultDataGridColumnHeaderStyle}"
CellContentStyle="{StaticResource DefaultDataGridTextCellStyle}" />
<tdg:DataGridTextColumn PropertyName="SecondaryId"
HeaderText="Secondary ID"
CanUserFilter="False"
IsVisible="False"
HeaderStyle="{StaticResource DefaultDataGridColumnHeaderStyle}"
CellContentStyle="{StaticResource DefaultDataGridTextCellStyle}" />
<tdg:DataGridDateColumn PropertyName="Start"
HeaderText="Start"
CanUserFilter="False"
CellContentFormat="{}{0:MM/dd/yy hh:mm:ss tt}"
HeaderStyle="{StaticResource DefaultDataGridColumnHeaderStyle}"
CellContentStyle="{StaticResource DefaultDataGridTextCellStyle}" />
<tdg:DataGridDateColumn PropertyName="End"
HeaderText="End"
CanUserFilter="False"
IsVisible="False"
CellContentFormat="{}{0:MM/dd/yy hh:mm:ss tt}"
HeaderStyle="{StaticResource DefaultDataGridColumnHeaderStyle}"
CellContentStyle="{StaticResource DefaultDataGridTextCellStyle}" />
<tdg:DataGridNumericalColumn PropertyName="ShiftNum"
HeaderText="Shift #"
CanUserFilter="False"
IsVisible="False"
HeaderStyle="{StaticResource DefaultDataGridColumnHeaderStyle}"
CellContentStyle="{StaticResource DefaultDataGridTextCellStyle}" />
<tdg:DataGridNumericalColumn PropertyName="ShiftHr"
HeaderText="Shift Hour"
IsVisible="False"
HeaderStyle="{StaticResource DefaultDataGridColumnHeaderStyle}"
CellContentStyle="{StaticResource DefaultDataGridTextCellStyle}" />
<tdg:DataGridNumericalColumn PropertyName="ShiftMins"
HeaderText="Shift Minutes"
CanUserFilter="False"
IsVisible="False"
HeaderStyle="{StaticResource DefaultDataGridColumnHeaderStyle}"
CellContentStyle="{StaticResource DefaultDataGridTextCellStyle}" />
<tdg:DataGridTextColumn PropertyName="Line"
HeaderText="Line"
CanUserFilter="False"
IsVisible="False"
HeaderStyle="{StaticResource DefaultDataGridColumnHeaderStyle}"
CellContentStyle="{StaticResource DefaultDataGridTextCellStyle}" />
<tdg:DataGridTextColumn PropertyName="Station"
HeaderText="Station"
CanUserFilter="False"
HeaderStyle="{StaticResource DefaultDataGridColumnHeaderStyle}"
CellContentStyle="{StaticResource DefaultDataGridTextCellStyle}" />
<tdg:DataGridTextColumn PropertyName="Status"
HeaderText="Status"
CanUserFilter="False"
HeaderStyle="{StaticResource DefaultDataGridColumnHeaderStyle}"
CellContentStyle="{StaticResource DefaultDataGridTextCellStyle}" />
<tdg:DataGridTextColumn PropertyName="Description"
HeaderText="Description"
CanUserFilter="False"
IsVisible="False"
HeaderStyle="{StaticResource DefaultDataGridColumnHeaderStyle}"
CellContentStyle="{StaticResource DefaultDataGridTextCellStyle}" />
</tdg:RadDataGrid.Columns>
</tdg:RadDataGrid>
Exception:
2018-10-22 14:56:01.776266-0400 Dynimetrics.iOS[9217:125873]
Unhandled Exception:
System.NullReferenceException: Object reference not set to an instance of an object
at Xamarin.Forms.Platform.iOS.VisualElementRenderer`1[TElement].UpdateTabStop () [0x00000] in D:\a\1\s\Xamarin.Forms.Platform.iOS\VisualElementRenderer.cs:159
at Xamarin.Forms.Platform.iOS.VisualElementRenderer`1[TElement].Xamarin.Forms.Platform.iOS.IVisualElementRenderer.SetElement (Xamarin.Forms.VisualElement element) [0x0000c] in D:\a\1\s\Xamarin.Forms.Platform.iOS\VisualElementRenderer.cs:142
at Telerik.XamarinForms.Common.RadPlatform.RetireRenderer (Xamarin.Forms.VisualElement visualElement) [0x0001a] in <854ee8369bca461384d3ac3224bfd96a>:0
at Telerik.XamarinForms.Common.iOS.RadViewContainer.ClearContainer () [0x00075] in <854ee8369bca461384d3ac3224bfd96a>:0
at Telerik.XamarinForms.Common.iOS.RadViewContainer.Dispose (System.Boolean disposing) [0x0000a] in <854ee8369bca461384d3ac3224bfd96a>:0
at Foundation.NSObject.Dispose
() [0x00000] in /Library/Frameworks/Xamarin.iOS.framework/Versions/12.0.0.15/src/Xamarin.iOS/Foundation/NSObject2.cs:147
at Telerik.XamarinForms.PrimitivesRenderer.iOS.ScrollViewRenderer.RetireViewContainer (Telerik.XamarinForms.Common.iOS.RadViewContainer viewContainer) [0x00004] in <c4c4f7bc21d74b21927d9e243e48a659>:0
at Telerik.XamarinForms.PrimitivesRenderer.iOS.ScrollViewRenderer.OnElementContentChanged () [0x0000c] in <c4c4f7bc21d74b21927d9e243e48a659>:0
at Telerik.XamarinForms.PrimitivesRenderer.iOS.ScrollViewRenderer.OnElementDetached (Telerik.XamarinForms.Primitives.RadScrollView oldElement) [0x00032] in <c4c4f7bc21d74b21927d9e243e48a659>:0
at Telerik.XamarinForms.Common.iOS.IosRendererBase`2[S,T].OnElementChanged (Xamarin.Forms.Platform.iOS.ElementChangedEventArgs`1[TElement] e) [0x00016] in <854ee8369bca461384d3ac3224bfd96a>:0
at Xamarin.Forms.Platform.iOS.VisualElementRenderer`1[TElement].SetElement (TElement element) [0x00122] in D:\a\1\s\Xamarin.Forms.Platform.iOS\VisualElementRen
derer.cs:259
at Xamarin.Forms.Platform.iOS.VisualElementRenderer`1[TElement].Dispose (System.Boolean disposing) [0x0008c] in D:\a\1\s\Xamarin.Forms.Platform.iOS\VisualElementRenderer.cs:340
at Xamarin.Forms.Platform.iOS.ViewRenderer`2[TView,TNativeView].Dispose (System.Boolean disposing) [0x00000] in D:\a\1\s\Xamarin.Forms.Platform.iOS\ViewRenderer.cs:84
at Foundation.NSObject.Dispose () [0x00000] in /Library/Frameworks/Xamarin.iOS.framework/Versions/12.0.0.15/src/Xamarin.iOS/Foundation/NSObject2.cs:147
at Xamarin.Forms.Platform.iOS.VisualElementPackager.Dispose (System.Boolean disposing) [0x0003f] in D:\a\1\s\Xamarin.Forms.Platform.iOS\VisualElementPackager.cs:69
at Xamarin.Forms.Platform.iOS.VisualElementPackager.Dispose () [0x00000] in D:\a\1\s\Xamarin.Forms.Platform.iOS\VisualElementPackager.cs:37
at Xamarin.Forms.Platform.iOS.VisualElementRenderer`1[TElement].Dispose (System.Boolean disposing) [0x00058] in D:\a\1\s\Xamarin.Forms.Platform.iOS\VisualElementRenderer.cs:331
at Foundation
.NSObject.Dispose () [0x00000] in /Library/Frameworks/Xamarin.iOS.framework/Versions/12.0.0.15/src/Xamarin.iOS/Foundation/NSObject2.cs:147
at Xamarin.Forms.Platform.iOS.VisualElementPackager.Dispose (System.Boolean disposing) [0x0003f] in D:\a\1\s\Xamarin.Forms.Platform.iOS\VisualElementPackager.cs:69
at Xamarin.Forms.Platform.iOS.VisualElementPackager.Dispose () [0x00000] in D:\a\1\s\Xamarin.Forms.Platform.iOS\VisualElementPackager.cs:37
at Xamarin.Forms.Platform.iOS.VisualElementRenderer`1[TElement].Dispose (System.Boolean disposing) [0x00058] in D:\a\1\s\Xamarin.Forms.Platform.iOS\VisualElementRenderer.cs:331
at Foundation.NSObject.Dispose () [0x00000] in /Library/Frameworks/Xamarin.iOS.framework/Versions/12.0.0.15/src/Xamarin.iOS/Foundation/NSObject2.cs:147
at Xamarin.Forms.Platform.iOS.VisualElementPackager.Dispose (System.Boolean disposing) [0x0003f] in D:\a\1\s\Xamarin.Forms.Platform.iOS\VisualElementPackager.cs:69
at Xamarin.Forms.Platform.iOS.VisualElementPackager.Dispose () [0x0000
0] in D:\a\1\s\Xamarin.Forms.Platform.iOS\VisualElementPackager.cs:37
at Xamarin.Forms.Platform.iOS.PageRenderer.Dispose (System.Boolean disposing) [0x00070] in D:\a\1\s\Xamarin.Forms.Platform.iOS\Renderers\PageRenderer.cs:164
at Foundation.NSObject.Dispose () [0x00000] in /Library/Frameworks/Xamarin.iOS.framework/Versions/12.0.0.15/src/Xamarin.iOS/Foundation/NSObject2.cs:147
at Xamarin.Forms.Platform.iOS.DisposeHelpers.DisposeModalAndChildRenderers (Xamarin.Forms.Element view) [0x00038] in D:\a\1\s\Xamarin.Forms.Platform.iOS\DisposeHelpers.cs:17
at Xamarin.Forms.Platform.iOS.Platform.HandleChildRemoved (System.Object sender, Xamarin.Forms.ElementEventArgs e) [0x00006] in D:\a\1\s\Xamarin.Forms.Platform.iOS\Platform.cs:297
at Xamarin.Forms.Element.OnDescendantRemoved (Xamarin.Forms.Element child) [0x00000] in D:\a\1\s\Xamarin.Forms.Core\Element.cs:617
at Xamarin.Forms.Element.OnChildRemoved (Xamarin.Forms.Element child) [0x0001f] in D:\a\1\s\Xamarin.Forms.Core\Element.cs:357
at Xamarin.Fo
rms.VisualElement.OnChildRemoved (Xamarin.Forms.Element child) [0x00000] in D:\a\1\s\Xamarin.Forms.Core\VisualElement.cs:748
at Xamarin.Forms.Page.OnInternalRemoved (Xamarin.Forms.VisualElement view) [0x00013] in D:\a\1\s\Xamarin.Forms.Core\Page.cs:380
at Xamarin.Forms.Page.InternalChildrenOnCollectionChanged (System.Object sender, System.Collections.Specialized.NotifyCollectionChangedEventArgs e) [0x00022] in D:\a\1\s\Xamarin.Forms.Core\Page.cs:358
at System.Collections.ObjectModel.ObservableCollection`1[T].OnCollectionChanged (System.Collections.Specialized.NotifyCollectionChangedEventArgs e) [0x0000f] in /Library/Frameworks/Xamarin.iOS.framework/Versions/12.0.0.15/src/Xamarin.iOS/mcs/class/referencesource/System/compmod/system/collections/objectmodel/observablecollection.cs:288
at System.Collections.ObjectModel.ObservableCollection`1[T].OnCollectionChanged (System.Collections.Specialized.NotifyCollectionChangedAction action, System.Object item, System.Int32 index) [0x00000] in /Library/Framewor
ks/Xamarin.iOS.framework/Versions/12.0.0.15/src/Xamarin.iOS/mcs/class/referencesource/System/compmod/system/collections/objectmodel/observablecollection.cs:351
at System.Collections.ObjectModel.ObservableCollection`1[T].RemoveItem (System.Int32 index) [0x0002b] in /Library/Frameworks/Xamarin.iOS.framework/Versions/12.0.0.15/src/Xamarin.iOS/mcs/class/referencesource/System/compmod/system/collections/objectmodel/observablecollection.cs:205
at System.Collections.ObjectModel.Collection`1[T].Remove (T item) [0x00027] in /Library/Frameworks/Xamarin.iOS.framework/Versions/12.0.0.15/src/Xamarin.iOS/mcs/class/referencesource/mscorlib/system/collections/objectmodel/collection.cs:113
at Xamarin.Forms.MasterDetailPage.set_Detail (Xamarin.Forms.Page value) [0x0004b] in D:\a\1\s\Xamarin.Forms.Core\MasterDetailPage.cs:44
at Dynimetrics.UI.Views.MainPage+<NavigateFromMenu>d__6.MoveNext () [0x0006f] in C:\src\PlantFloorConnect\Dynimetrics\Dynimetrics.UI\Views\MainPage.xaml.cs:54
--- End of stack trace from previo
us location where exception was thrown ---
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Threading.Tasks.Task task) [0x00037] in /Library/Frameworks/Xamarin.iOS.framework/Versions/12.0.0.15/src/Xamarin.iOS/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:187
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Threading.Tasks.Task task) [0x00028] in /Library/Frameworks/Xamarin.iOS.framework/Versions/12.0.0.15/src/Xamarin.iOS/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:156
at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd (System.Threading.Tasks.Task task) [0x00008] in /Library/Frameworks/Xamarin.iOS.framework/Versions/12.0.0.15/src/Xamarin.iOS/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:128
at System.Runtime.CompilerServices.TaskAwaiter.GetResult () [0x00000] in /Library/Frameworks/Xamarin.iOS.framework/Versions/1
2.0.0.15/src/Xamarin.iOS/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:113
at Dynimetrics.UI.Views.MenuPage+<<-ctor>b__3_0>d.MoveNext () [0x0005d] in C:\src\PlantFloorConnect\Dynimetrics\Dynimetrics.UI\Views\MenuPage.xaml.cs:54
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.CompilerServices.AsyncMethodBuilderCore+<>c.<ThrowAsync>b__6_0 (System.Object state) [0x00000] in /Library/Frameworks/Xamarin.iOS.framework/Versions/12.0.0.15/src/Xamarin.iOS/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/AsyncMethodBuilder.cs:1018
at Foundation.NSAsyncSynchronizationContextDispatcher.Apply () [0x00000] in /Library/Frameworks/Xamarin.iOS.framework/Versions/12.0.0.15/src/Xamarin.iOS/Foundation/NSAction.cs:178
--- End of stack trace from previous location where exception was thrown ---
at (wrapper managed-to-native) UIKit.UIApplication.UIApplicationMain(int,string[],intptr,intptr)
at UIKit.UIApplication.Main
(System.String[] args, System.IntPtr principal, System.IntPtr delegate) [0x00005] in /Library/Frameworks/Xamarin.iOS.framework/Versions/12.0.0.15/src/Xamarin.iOS/UIKit/UIApplication.cs:79
at UIKit.UIApplication.Main (System.String[] args, System.String principalClassName, System.String delegateClassName) [0x0002c] in /Library/Frameworks/Xamarin.iOS.framework/Versions/12.0.0.15/src/Xamarin.iOS/UIKit/UIApplication.cs:63
at Dynimetrics.iOS.Application.Main (System.String[] args) [0x00001] in C:\src\PlantFloorConnect\Dynimetrics\Dynimetrics.UI.iOS\Main.cs:17
2018-10-22 14:56:01.780638-0400 Dynimetrics.iOS[9217:125873] Unhandled managed exception:
Object reference not set to an instance of an object (System.NullReferenceException)
at Xamarin.Forms.Platform.iOS.VisualElementRenderer`1[TElement].UpdateTabStop () [0x00000] in D:\a\1\s\Xamarin.Forms.Platform.iOS\VisualElementRenderer.cs:159
at Xamarin.Forms.Platform.iOS.VisualElementRenderer`1[TElement].Xamarin.Forms.Platform.iOS.IVisualElementRenderer.SetE
lement (Xamarin.Forms.VisualElement element) [0x0000c] in D:\a\1\s\Xamarin.Forms.Platform.iOS\VisualElementRenderer.cs:142
at Telerik.XamarinForms.Common.RadPlatform.RetireRenderer (Xamarin.Forms.VisualElement visualElement) [0x0001a] in <854ee8369bca461384d3ac3224bfd96a>:0
at Telerik.XamarinForms.Common.iOS.RadViewContainer.ClearContainer () [0x00075] in <854ee8369bca461384d3ac3224bfd96a>:0
at Telerik.XamarinForms.Common.iOS.RadViewContainer.Dispose (System.Boolean disposing) [0x0000a] in <854ee8369bca461384d3ac3224bfd96a>:0
at Foundation.NSObject.Dispose () [0x00000] in /Library/Frameworks/Xamarin.iOS.framework/Versions/12.0.0.15/src/Xamarin.iOS/Foundation/NSObject2.cs:147
at Telerik.XamarinForms.PrimitivesRenderer.iOS.ScrollViewRenderer.RetireViewContainer (Telerik.XamarinForms.Common.iOS.RadViewContainer viewContainer) [0x00004] in <c4c4f7bc21d74b21927d9e243e48a659>:0
at Telerik.XamarinForms.PrimitivesRenderer.iOS.ScrollViewRenderer.OnElementContentChanged () [0x0000c] in <c4c4f7bc21d74b
21927d9e243e48a659>:0
at Telerik.XamarinForms.PrimitivesRenderer.iOS.ScrollViewRenderer.OnElementDetached (Telerik.XamarinForms.Primitives.RadScrollView oldElement) [0x00032] in <c4c4f7bc21d74b21927d9e243e48a659>:0
at Telerik.XamarinForms.Common.iOS.IosRendererBase`2[S,T].OnElementChanged (Xamarin.Forms.Platform.iOS.ElementChangedEventArgs`1[TElement] e) [0x00016] in <854ee8369bca461384d3ac3224bfd96a>:0
at Xamarin.Forms.Platform.iOS.VisualElementRenderer`1[TElement].SetElement (TElement element) [0x00122] in D:\a\1\s\Xamarin.Forms.Platform.iOS\VisualElementRenderer.cs:259
at Xamarin.Forms.Platform.iOS.VisualElementRenderer`1[TElement].Dispose (System.Boolean disposing) [0x0008c] in D:\a\1\s\Xamarin.Forms.Platform.iOS\VisualElementRenderer.cs:340
at Xamarin.Forms.Platform.iOS.ViewRenderer`2[TView,TNativeView].Dispose (System.Boolean disposing) [0x00000] in D:\a\1\s\Xamarin.Forms.Platform.iOS\ViewRenderer.cs:84
at Foundation.NSObject.Dispose () [0x00000] in /Library/Frameworks/Xamarin.iOS.fram
ework/Versions/12.0.0.15/src/Xamarin.iOS/Foundation/NSObject2.cs:147
at Xamarin.Forms.Platform.iOS.VisualElementPackager.Dispose (System.Boolean disposing) [0x0003f] in D:\a\1\s\Xamarin.Forms.Platform.iOS\VisualElementPackager.cs:69
at Xamarin.Forms.Platform.iOS.VisualElementPackager.Dispose () [0x00000] in D:\a\1\s\Xamarin.Forms.Platform.iOS\VisualElementPackager.cs:37
at Xamarin.Forms.Platform.iOS.VisualElementRenderer`1[TElement].Dispose (System.Boolean disposing) [0x00058] in D:\a\1\s\Xamarin.Forms.Platform.iOS\VisualElementRenderer.cs:331
at Foundation.NSObject.Dispose () [0x00000] in /Library/Frameworks/Xamarin.iOS.framework/Versions/12.0.0.15/src/Xamarin.iOS/Foundation/NSObject2.cs:147
at Xamarin.Forms.Platform.iOS.VisualElementPackager.Dispose (System.Boolean disposing) [0x0003f] in D:\a\1\s\Xamarin.Forms.Platform.iOS\VisualElementPackager.cs:69
at Xamarin.Forms.Platform.iOS.VisualElementPackager.Dispose () [0x00000] in D:\a\1\s\Xamarin.Forms.Platform.iOS\VisualElementPackager.cs:37
at Xamarin.Forms.Platform.iOS.VisualElementRenderer`1[TElement].Dispose (System.Boolean disposing) [0x00058] in D:\a\1\s\Xamarin.Forms.Platform.iOS\VisualElementRenderer.cs:331
at Foundation.NSObject.Dispose () [0x00000] in /Library/Frameworks/Xamarin.iOS.framework/Versions/12.0.0.15/src/Xamarin.iOS/Foundation/NSObject2.cs:147
at Xamarin.Forms.Platform.iOS.VisualElementPackager.Dispose (System.Boolean disposing) [0x0003f] in D:\a\1\s\Xamarin.Forms.Platform.iOS\VisualElementPackager.cs:69
at Xamarin.Forms.Platform.iOS.VisualElementPackager.Dispose () [0x00000] in D:\a\1\s\Xamarin.Forms.Platform.iOS\VisualElementPackager.cs:37
at Xamarin.Forms.Platform.iOS.PageRenderer.Dispose (System.Boolean disposing) [0x00070] in D:\a\1\s\Xamarin.Forms.Platform.iOS\Renderers\PageRenderer.cs:164
at Foundation.NSObject.Dispose () [0x00000] in /Library/Frameworks/Xamarin.iOS.framework/Versions/12.0.0.15/src/Xamarin.iOS/Foundation/NSObject2.cs:147
at Xamarin.Forms.Platform.iOS.DisposeHelpers.DisposeModalAndC
hildRenderers (Xamarin.Forms.Element view) [0x00038] in D:\a\1\s\Xamarin.Forms.Platform.iOS\DisposeHelpers.cs:17
at Xamarin.Forms.Platform.iOS.Platform.HandleChildRemoved (System.Object sender, Xamarin.Forms.ElementEventArgs e) [0x00006] in D:\a\1\s\Xamarin.Forms.Platform.iOS\Platform.cs:297
at Xamarin.Forms.Element.OnDescendantRemoved (Xamarin.Forms.Element child) [0x00000] in D:\a\1\s\Xamarin.Forms.Core\Element.cs:617
at Xamarin.Forms.Element.OnChildRemoved (Xamarin.Forms.Element child) [0x0001f] in D:\a\1\s\Xamarin.Forms.Core\Element.cs:357
at Xamarin.Forms.VisualElement.OnChildRemoved (Xamarin.Forms.Element child) [0x00000] in D:\a\1\s\Xamarin.Forms.Core\VisualElement.cs:748
at Xamarin.Forms.Page.OnInternalRemoved (Xamarin.Forms.VisualElement view) [0x00013] in D:\a\1\s\Xamarin.Forms.Core\Page.cs:380
at Xamarin.Forms.Page.InternalChildrenOnCollectionChanged (System.Object sender, System.Collections.Specialized.NotifyCollectionChangedEventArgs e) [0x00022] in D:\a\1\s\Xamarin.Forms.Core\P
age.cs:358
at System.Collections.ObjectModel.ObservableCollection`1[T].OnCollectionChanged (System.Collections.Specialized.NotifyCollectionChangedEventArgs e) [0x0000f] in /Library/Frameworks/Xamarin.iOS.framework/Versions/12.0.0.15/src/Xamarin.iOS/mcs/class/referencesource/System/compmod/system/collections/objectmodel/observablecollection.cs:288
at System.Collections.ObjectModel.ObservableCollection`1[T].OnCollectionChanged (System.Collections.Specialized.NotifyCollectionChangedAction action, System.Object item, System.Int32 index) [0x00000] in /Library/Frameworks/Xamarin.iOS.framework/Versions/12.0.0.15/src/Xamarin.iOS/mcs/class/referencesource/System/compmod/system/collections/objectmodel/observablecollection.cs:351
at System.Collections.ObjectModel.ObservableCollection`1[T].RemoveItem (System.Int32 index) [0x0002b] in /Library/Frameworks/Xamarin.iOS.framework/Versions/12.0.0.15/src/Xamarin.iOS/mcs/class/referencesource/System/compmod/system/collections/objectmodel/observablecollection.cs:205
a
t System.Collections.ObjectModel.Collection`1[T].Remove (T item) [0x00027] in /Library/Frameworks/Xamarin.iOS.framework/Versions/12.0.0.15/src/Xamarin.iOS/mcs/class/referencesource/mscorlib/system/collections/objectmodel/collection.cs:113
at Xamarin.Forms.MasterDetailPage.set_Detail (Xamarin.Forms.Page value) [0x0004b] in D:\a\1\s\Xamarin.Forms.Core\MasterDetailPage.cs:44
at Dynimetrics.UI.Views.MainPage+<NavigateFromMenu>d__6.MoveNext () [0x0006f] in C:\src\PlantFloorConnect\Dynimetrics\Dynimetrics.UI\Views\MainPage.xaml.cs:54
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Threading.Tasks.Task task) [0x00037] in /Library/Frameworks/Xamarin.iOS.framework/Versions/12.0.0.15/src/Xamarin.iOS/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:187
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Threading.Tasks.Task task) [0
x00028] in /Library/Frameworks/Xamarin.iOS.framework/Versions/12.0.0.15/src/Xamarin.iOS/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:156
at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd (System.Threading.Tasks.Task task) [0x00008] in /Library/Frameworks/Xamarin.iOS.framework/Versions/12.0.0.15/src/Xamarin.iOS/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:128
at System.Runtime.CompilerServices.TaskAwaiter.GetResult () [0x00000] in /Library/Frameworks/Xamarin.iOS.framework/Versions/12.0.0.15/src/Xamarin.iOS/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:113
at Dynimetrics.UI.Views.MenuPage+<<-ctor>b__3_0>d.MoveNext () [0x0005d] in C:\src\PlantFloorConnect\Dynimetrics\Dynimetrics.UI\Views\MenuPage.xaml.cs:54
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.CompilerServices.AsyncMethodBuilderCore+<>c.<ThrowAsync>b__6_0 (System.Object state)
[0x00000] in /Library/Frameworks/Xamarin.iOS.framework/Versions/12.0.0.15/src/Xamarin.iOS/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/AsyncMethodBuilder.cs:1018
at Foundation.NSAsyncSynchronizationContextDispatcher.Apply () [0x00000] in /Library/Frameworks/Xamarin.iOS.framework/Versions/12.0.0.15/src/Xamarin.iOS/Foundation/NSAction.cs:178
--- End of stack trace from previous location where exception was thrown ---
at (wrapper managed-to-native) UIKit.UIApplication.UIApplicationMain(int,string[],intptr,intptr)
at UIKit.UIApplication.Main (System.String[] args, System.IntPtr principal, System.IntPtr delegate) [0x00005] in /Library/Frameworks/Xamarin.iOS.framework/Versions/12.0.0.15/src/Xamarin.iOS/UIKit/UIApplication.cs:79
at UIKit.UIApplication.Main (System.String[] args, System.String principalClassName, System.String delegateClassName) [0x0002c] in /Library/Frameworks/Xamarin.iOS.framework/Versions/12.0.0.15/src/Xamarin.iOS/UIKit/UIApplication.cs:63
at Dynimetrics.iOS.Ap
plication.Main (System.String[] args) [0x00001] in C:\src\PlantFloorConnect\Dynimetrics\Dynimetrics.UI.iOS\Main.cs:17