Xamarin.forms: [Bug] System.ObjectDisposedException: 'Cannot access a disposed object. Object name: 'GroupableItemsViewController`1'

Created on 6 Nov 2019  ·  19Comments  ·  Source: xamarin/Xamarin.Forms

Description

On iOS a Shell App with CollectionView crashes. Android works.

Steps to Reproduce

  1. Login and GoTo //main/computers/root which loads the page with a CollectionView (computer:ComputersRootPage).
  2. Tap on TabBar to AccountPage (local:AccountPage)
  3. Tap on TabBar to computer:ComputersRootPage (like in 1st step)
  4. App crashes.

Shell AppShell.xaml structure:

<ShellItem Route="login">
    <ShellContent ContentTemplate="{DataTemplate local:LoginPage}"/>
</ShellItem>

<TabBar Route="main">
    <Tab Title="Computers" Icon="computers.png" Route="computers">
        <ShellContent ContentTemplate="{DataTemplate computer:ComputersRootPage}" 
                      Title="Root"
                      Route="root"
                      />
    </Tab>
    <Tab Title="Favorites" Icon="favorites.png">
        <ShellContent ContentTemplate="{DataTemplate local:FavoritesPage}" />
    </Tab>
    <Tab Title="Active" Icon="active.png">
        <ShellContent ContentTemplate="{DataTemplate local:ActivePage}" />
    </Tab>
    <Tab Title="Users" Icon="users.png">
        <ShellContent ContentTemplate="{DataTemplate local:UsersPage}" />
    </Tab>
    <Tab Title="Account" Icon="account.png">
        <ShellContent ContentTemplate="{DataTemplate local:AccountPage}" />
    </Tab>
</TabBar>

ComputersRootPage XAML structure

<?xml version="1.0" encoding="utf-8"?>

<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             xmlns:d="http://xamarin.com/schemas/2014/forms/design"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
             xmlns:forms="clr-namespace:FFImageLoading.Svg.Forms;assembly=FFImageLoading.Svg.Forms"
             Style="{StaticResource ContentPageBase}"
             mc:Ignorable="d"
             x:Class="Next.Remoted.Views.Computers.ComputersRootPage"
             Shell.NavBarIsVisible="True"
             x:Name="Self">

    <Shell.TitleView>
        <Label x:Name="TitleView"
               Opacity="0"
               HorizontalTextAlignment="Center"
               VerticalTextAlignment="Center"
               HorizontalOptions="CenterAndExpand"
               FontAttributes="Bold"
               TextColor="{StaticResource AppBlue}"
               Text="{Binding ComputersTitleText.Result}" />
    </Shell.TitleView>
    <ContentPage.ToolbarItems>
        <ToolbarItem IconImageSource="search" Command="{Binding SearchCommand}" />
    </ContentPage.ToolbarItems>


    <RefreshView IsRefreshing="{Binding IsRefreshing}"
                 Command="{Binding InitialLoadCommand}">
        <CollectionView x:Name="ComputersRootFolderView"
                        ItemsSource="{Binding RemotedEntries}"
                        SelectionMode="Single"
                        SelectionChanged="SelectableItemsView_OnSelectionChanged"
                        Scrolled="ItemsView_OnScrolled">
            <CollectionView.Header>
                <StackLayout HeightRequest="100">
                    <Label x:Name="HeaderTitle"
                           Text="{Binding Source={x:Reference Self}, Path=BindingContext.ComputersTitleText.Result}"
                           HorizontalOptions="CenterAndExpand"
                           Margin="0,20,0,0"
                           Style="{StaticResource ComputersPageLabel}" />
                    <Label
                        Text="{Binding Source={x:Reference Self}, Path=BindingContext.RemotedEntries.Count, StringFormat='{0}'}"
                        HorizontalTextAlignment="Center"
                        TextColor="{StaticResource AppLightBlue}"
                        Margin="5,10,0,10" />
                    <BoxView HeightRequest="1" HorizontalOptions="FillAndExpand" Color="{StaticResource AppBlue}" />
                </StackLayout>
            </CollectionView.Header>
            <CollectionView.EmptyView>
                <ActivityIndicator  IsRunning="True"
                                    Color="{StaticResource AppBlue}"
                                    BackgroundColor="{StaticResource AppDarkBlue}" />
            </CollectionView.EmptyView>
            <CollectionView.ItemTemplate>
                <DataTemplate>
                    <Grid Padding="0,5,0,0">
                        <Grid.RowDefinitions>
                            <RowDefinition Height="Auto" />
                        </Grid.RowDefinitions>
                        <Grid.ColumnDefinitions>
                            <ColumnDefinition Width="Auto" />
                            <ColumnDefinition Width="*" />
                            <ColumnDefinition Width="Auto" />
                        </Grid.ColumnDefinitions>

                        <forms:SvgCachedImage
                            Grid.Column="0"
                            WidthRequest="30"
                            HeightRequest="30"
                            Style="{StaticResource FfimageLandingStyle}"
                            Source="resource://Next.Remoted.Resources.folder_closed.svg" />

                        <Label
                            Grid.Column="1"
                            Style="{StaticResource ComputersPageLabel}"
                            Text="{Binding Name}" />

                        <forms:SvgCachedImage
                            Grid.Column="2"
                            WidthRequest="{OnPlatform Default=30,iOS=40}"
                            HeightRequest="{OnPlatform Default=30,iOS=40}"
                            Style="{StaticResource FfimageLandingStyle}"
                            Source="resource://Next.Remoted.Resources.more_static.svg">
                            <forms:SvgCachedImage.GestureRecognizers>
                                <TapGestureRecognizer
                                    Command="{Binding Path=BindingContext.ShowMoreCommand, Source={x:Reference Name=ComputersRootFolderView}}"
                                    CommandParameter="{Binding .}"
                                    NumberOfTapsRequired="1" />
                            </forms:SvgCachedImage.GestureRecognizers>
                        </forms:SvgCachedImage>
                    </Grid>
                </DataTemplate>
            </CollectionView.ItemTemplate>
        </CollectionView>
    </RefreshView>
</ContentPage>

Expected Behavior

No crash.

Actual Behavior

iOS App crashes.

System.ObjectDisposedException: 'Cannot access a disposed object.
Object name: 'GroupableItemsViewController`1'

Basic Information

XF SDK Version: 4.3.0.947036 (latest stable)
IDE: Visual Studio 2019
Platform Target Frameworks:
iOS: 13.1, 13.2 (Probbably other versions too)
App Type: Xamarin.Forms

needs-info ❓ needs-repro ❔ unverified bug
Source
picture ericbrunner
👍3

Most helpful comment

I can reproduce with iOS 12.2 and Xamarin.Forms 4.7.0.1239

picture donatellijl on 4 Aug 2020
👍6

All 19 comments

@pauldipietro based on your last blog post https://devblogs.microsoft.com/xamarin/xamarin-forms-4-3-introducing-collectionview/
I developed my production app with the CollectionView. Because you wrote it is not experimental anymore. I appreciate your posts, but please take more care with such announcements. Now I have to revert back to ListView views.

ericbrunner picture ericbrunner on 6 Nov 2019
👍2

@ericbrunner I'm trying to reproduce this error, but I'm not having much luck so far. Can you post a minimal repro project which demonstrates it?

hartez picture hartez on 17 Nov 2019

Fix pls

kcrg picture kcrg on 3 Dec 2019

@kcrg @ericbrunner

  • can you provide a repro? and/or provide a full stack trace? Though a repro would help us fix this super quick
  • test with the latest?
PureWeen picture PureWeen on 7 Dec 2019

@PureWeen All that information is inside my comment from 6th of November. Create a new Xamarin.Forms Shell API without REST API Backend. Update the data-bindings in the XAML. Adjust the AppShell.xaml to the structure I posted. I will try to create such repo

ericbrunner picture ericbrunner on 7 Dec 2019

@ericbrunner aw I had missed that there was an existing issue this linked to

So can we just close this one in favor of https://github.com/xamarin/Xamarin.Forms/issues/8308 . ?

Seems like that one already has a repro and is confirmed

PureWeen picture PureWeen on 7 Dec 2019

@PureWeen No you can't close this issue until solved. The other issue is different. There is mentioned that there is no issue on tabs. Well my filed issue is totally tabbar related / collectionview issue on iOS.

ericbrunner picture ericbrunner on 7 Dec 2019

Sounds good! Though I'm fairly confident once that one is solved it'll fix this one :-)

In either case, a full stack trace would also be helpful

PureWeen picture PureWeen on 7 Dec 2019

I'll create a repo tomorrow and upload it

ericbrunner picture ericbrunner on 7 Dec 2019

@PureWeen

Ok i created a repo. In the meanwhile new Xamarin.Forms SDK versions were released. I updated to

Xamarin.Forms SDK: 4.4.0.936621-pre1

The iOS App doesn't crash now anymore, which is an improvement. But there are still related Debug Log outputs.

You can reproduce it when you pull down to refresh.

2019-12-08 07:57:00.943926+0100 ShellHotrestartAppTest.iOS[96794:8599051] [UICollectionView] Invalid update: invalid number of items in section 0.  The number of items contained in an existing section after the update (1) must be equal to the number of items contained in that section before the update (1), plus or minus the number of items inserted or deleted from that section (1 inserted, 0 deleted) and plus or minus the number of items moved into or out of that section (0 moved in, 0 moved out). - will perform reloadData. UICollectionView instance: <UICollectionView: 0x7f983443b000; frame = (0 0; 414 725); clipsToBounds = YES; autoresize = W+H; gestureRecognizers = <NSArray: 0x600000e809c0>; layer = <CALayer: 0x60000073d100>; contentOffset: {0, -160}; contentSize: {414, 45}; adjustedContentInset: {160, 0, 0, 0}; layout: <Xamarin_Forms_Platform_iOS_ListViewLayout: 0x7f9832e35810>; dataSource: <Xamarin_Forms_Platform_iOS_GroupableItemsViewController_1: 0x7f9832e488c0>>; currentUpdate: [UICollectionViewUpdate 
- 0x7f9832e6ddf0: old:<UICollectionViewData: 0x6000039c0d20> new<UICollectionViewData: 0x60000393ed80> items:<(
    "I(0,0)"
)>]

ios_collectionview
ShellHotrestartAppTest.zip

ericbrunner picture ericbrunner on 8 Dec 2019

The latest warnings should be fixed by: https://github.com/xamarin/Xamarin.Forms/pull/7711

jsuarezruiz picture jsuarezruiz on 9 Dec 2019
👍1

@jsuarezruiz In that case I close that issue

ericbrunner picture ericbrunner on 10 Dec 2019

Please re-open this issue, we receive this error Inserting items into an ObservableCollection on iOS Simulator, running Xamarin.Forms 4.4.0.991265

FlatlinerDOA picture FlatlinerDOA on 8 Jan 2020
👍3

Guys, we are experiencing the issue on iOS, on last stable version of XF related to navigation

2020-02-08 01:44:44.737620+0200 IRA.iOS[27782:209679] Unhandled managed exception: Cannot access a disposed object. Object name: 'ParentingViewController'. (System.ObjectDisposedException) at Foundation.NSObject.get_SuperHandle () [0x00012] in /Library/Frameworks/Xamarin.iOS.framework/Versions/13.10.0.17/src/Xamarin.iOS/Foundation/NSObject2.cs:449 at UIKit.UIViewController.get_NavigationItem () [0x0002a] in /Library/Frameworks/Xamarin.iOS.framework/Versions/13.10.0.17/src/Xamarin.iOS/UIViewController.g.cs:2303 at Xamarin.Forms.Platform.iOS.NavigationRenderer+<>c__DisplayClass76_0.<SetMasterLeftBarButton>b__0 (UIKit.UIImage icon) [0x0002c] in D:\a\1\s\Xamarin.Forms.Platform.iOS\Renderers\NavigationRenderer.cs:761 at Xamarin.Forms.Platform.iOS.ImageElementManager.ApplyNativeImageAsync (Xamarin.Forms.BindableObject bindable, Xamarin.Forms.BindableProperty imageSourceProperty, System.Action1[T] onSet, System.Action1[T] onLoading, System.Threading.CancellationToken cancellationToken) [0x000fd] in D:\a \1\s\Xamarin.Forms.Platform.iOS\Renderers\ImageElementManager.cs:281 at Xamarin.Forms.Platform.iOS.NavigationRenderer.SetMasterLeftBarButton (UIKit.UIViewController containerController, Xamarin.Forms.MasterDetailPage masterDetailPage) [0x0007f] in D:\a\1\s\Xamarin.Forms.Platform.iOS\Renderers\NavigationRenderer.cs:747 at System.Runtime.CompilerServices.AsyncMethodBuilderCore+<>c.<ThrowAsync>b__7_0 (System.Object state) [0x00000] in /Library/Frameworks/Xamarin.iOS.framework/Versions/Current/src/Xamarin.iOS/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/AsyncMethodBuilder.cs:1021 at Foundation.NSAsyncSynchronizationContextDispatcher.Apply () [0x00000] in /Library/Frameworks/Xamarin.iOS.framework/Versions/13.10.0.17/src/Xamarin.iOS/Foundation/NSAction.cs:178 --- End of stack trace from previous location where exception was thrown ---

2020-02-08 01:27:04.306090+0200 IRA.iOS[24737:184880] Unhandled managed exception: Cannot access a disposed object. Object name: 'PrimaryToolbarItem'. (System.ObjectDisposedException) at Foundation.NSObject.get_SuperHandle () [0x00012] in /Library/Frameworks/Xamarin.iOS.framework/Versions/13.10.0.17/src/Xamarin.iOS/Foundation/NSObject2.cs:449 at UIKit.UIBarButtonItem.set_Image (UIKit.UIImage value) [0x00033] in /Library/Frameworks/Xamarin.iOS.framework/Versions/13.10.0.17/src/Xamarin.iOS/UIBarButtonItem.g.cs:652 at Xamarin.Forms.Platform.iOS.ToolbarItemExtensions+PrimaryToolbarItem.UpdateIconAndStyle () [0x00031] in D:\a\1\s\Xamarin.Forms.Platform.iOS\Extensions\ToolbarItemExtensions.cs:84 at System.Runtime.CompilerServices.AsyncMethodBuilderCore+<>c.<ThrowAsync>b__7_0 (System.Object state) [0x00000] in /Library/Frameworks/Xamarin.iOS.framework/Versions/Current/src/Xamarin.iOS/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/AsyncMethodBuilder.cs:1021 at Foundation.NSAsyncSynch ronizationContextDispatcher.Apply () [0x00000] in /Library/Frameworks/Xamarin.iOS.framework/Versions/13.10.0.17/src/Xamarin.iOS/Foundation/NSAction.cs:178 --- End of stack trace from previous location where exception was thrown ---

furiozo picture furiozo on 10 Feb 2020

@PureWeen @hartez Please fix this critical bug.

g4mb10r picture g4mb10r on 12 Feb 2020
👍3

I also get it randomly.

lnaie picture lnaie on 15 Feb 2020

I can reproduce this 2 of 3 times 😢 with iOS v12.4 & Xamarin.Forms v4.7.0.1080, but in iOS v13.5 & v13.6 I can't reproduce it🧐

Update:

With version Xamarin.Forms 4.6.0.1180 this bug is not reproducible at iOS v12.4

bbenetskyy picture bbenetskyy on 30 Jul 2020

I can reproduce with iOS 12.2 and Xamarin.Forms 4.7.0.1239

donatellijl picture donatellijl on 4 Aug 2020
👍6

I have this error. Xamarin Team, any news?

FetFrumos picture FetFrumos on 23 Nov 2020
Was this page helpful?
0 / 5 - 0 ratings

Related issues

AppGrate picture AppGrate  ·  3Comments
EmilAlipiev picture EmilAlipiev  ·  3Comments
fazil1987 picture fazil1987  ·  3Comments
jamiewest picture jamiewest  ·  3Comments
deakjahn picture deakjahn  ·  3Comments