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Maui Android Crash CarouselView IndicatorView on navigating second time

See original GitHub issue

Description

Maui Android Crash when there is CarouselView with IndicatorView and navigating second time to the page .

<CarouselView ItemsSource="{Binding Item.ProductFiles}" IndicatorView="myIndicator">

        <CarouselView.ItemTemplate>
            <DataTemplate x:DataType="model:ProductFileV2">                    
                <StackLayout>
                    <Frame HasShadow="True"
                   BorderColor="DarkGray"
                   CornerRadius="5"
                   Margin="20"
                   HeightRequest="300"
                   HorizontalOptions="Center"
                   VerticalOptions="CenterAndExpand">
                        <StackLayout>
                            <local:PinchToZoomContainer>
                                <Image Source="{Binding ThumbnailHostPathPublic}"
                               Aspect="AspectFill"
                               HeightRequest="150"
                               WidthRequest="150"
                               HorizontalOptions="Center" />
                            </local:PinchToZoomContainer>
                        </StackLayout>
                    </Frame>
                </StackLayout>                   
                </DataTemplate>
        </CarouselView.ItemTemplate>
    </CarouselView>
    <IndicatorView x:Name="myIndicator"
               IndicatorColor="LightGray"
               SelectedIndicatorColor="DarkGray"
               HorizontalOptions="Center" />

public ObservableCollection<ProductFile> ProductFileList { get; set; } = new ObservableCollection<ProductFile>(); void LoadProductFiles() { if (IsBusyProductFiles) { return; } IsBusyProductFiles = true;

        Task.Run(async () =>
        {                
            var items = await _ProductService.GetProductFiles(SearchModel);
            Application.Current.Dispatcher.Dispatch(() =>
            {                   
                ProductFileList.Clear();                   
                items?.Where(p => p.ProductFileType?.ProductFileTypeAction == ProductFileTypeAction.IsGallery)?
                                    .OrderBy(p => p.Importance)?
                                    .ToList()?.ForEach(p => ProductFileList.Add(p));

                IsBusyProductFiles = false;
            });
        });
    }

Steps to Reproduce

Link to public reproduction project repository

dont have

Version with bug

7.0 (current)

Last version that worked well

Unknown/Other

Affected platforms

Android

Affected platform versions

Android

Did you find any workaround?

Relevant log output

Time	Device Name	Type	PID	Tag	Message
11-12 16:40:11.425	pixel_5_-_api_33	Error	1788	AndroidRuntime	android.runtime.JavaProxyThrowable: System.InvalidOperationException: PlatformView cannot be null here
   at Microsoft.Maui.Handlers.ViewHandler`2[[Microsoft.Maui.IIndicatorView, Microsoft.Maui, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null],[Microsoft.Maui.Platform.MauiPageControl, Microsoft.Maui, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null]].get_PlatformView()
   at Microsoft.Maui.Handlers.IndicatorViewHandler.OnDisconnectHandler(View platformView)
   at Microsoft.Maui.Handlers.ViewHandler.OnDisconnectHandler(Object platformView)
   at Microsoft.Maui.Handlers.ElementHandler.DisconnectHandler(Object platformView)
   at Microsoft.Maui.Handlers.ElementHandler.Microsoft.Maui.IElementHandler.DisconnectHandler()
   at Microsoft.Maui.Controls.Element.SetHandler(IElementHandler newHandler)
   at Microsoft.Maui.Controls.Element.set_Handler(IElementHandler value)
   at Microsoft.Maui.Controls.VisualElement.Microsoft.Maui.IElement.set_Handler(IElementHandler value)
   at Microsoft.Maui.Platform.ElementExtensions.ToHandler(IElement view, IMauiContext context)
   at Microsoft.Maui.Platform.ElementExtensions.ToPlatform(IElement view, IMauiContext context)
   at Microsoft.Maui.Handlers.LayoutHandler.SetVirtualView(IView view)
   at Microsoft.Maui.Handlers.ViewHandler`2[[Microsoft.Maui.ILayout, Microsoft.Maui, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null],[Microsoft.Maui.Platform.LayoutViewGroup, Microsoft.Maui, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null]].SetVirtualView(IElement view)
   at Microsoft.Maui.Controls.Element.SetHandler(IElementHandler newHandler)
   at Microsoft.Maui.Controls.Element.set_Handler(IElementHandler value)
   at Microsoft.Maui.Controls.VisualElement.Microsoft.Maui.IElement.set_Handler(IElementHandler value)
   at Microsoft.Maui.Platform.ElementExtensions.ToHandler(IElement view, IMauiContext context)
   at Microsoft.Maui.Platform.ElementExtensions.ToPlatform(IElement view, IMauiContext context)
   at Microsoft.Maui.Handlers.ContentViewHandler.UpdateContent(IContentViewHandler handler)
   at Microsoft.Maui.Handlers.ContentViewHandler.MapContent(IContentViewHandler handler, IContentView page)
   at Microsoft.Maui.PropertyMapper`2.<>c__DisplayClass5_0[[Microsoft.Maui.IContentView, Microsoft.Maui, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null],[Microsoft.Maui.Handlers.IContentViewHandler, Microsoft.Maui, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null]].<Add>b__0(IElementHandler h, IElement v)
   at Microsoft.Maui.PropertyMapper.UpdatePropertyCore(String key, IElementHandler viewHandler, IElement virtualView)
   at Microsoft.Maui.PropertyMapper.UpdateProperties(IElementHandler viewHandler, IElement virtualView)
   at Microsoft.Maui.Handlers.ElementHandler.SetVirtualView(IElement view)
   at Microsoft.Maui.Handlers.ViewHandler.SetVirtualView(IElement element)
   at Microsoft.Maui.Handlers.ViewHandler`2[[Microsoft.Maui.IContentView, Microsoft.Maui, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null],[Microsoft.Maui.Platform.ContentViewGroup, Microsoft.Maui, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null]].SetVirtualView(IView view)
   at Microsoft.Maui.Handlers.ContentViewHandler.SetVirtualView(IView view)
   at Microsoft.Maui.Handlers.ViewHandler`2[[Microsoft.Maui.IContentView, Microsoft.Maui, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null],[Microsoft.Maui.Platform.ContentViewGroup, Microsoft.Maui, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null]].SetVirtualView(IElement view)
   at Microsoft.Maui.Controls.Element.SetHandler(IElementHandler newHandler)
   at Microsoft.Maui.Controls.Element.set_Handler(IElementHandler value)
   at Microsoft.Maui.Controls.VisualElement.Microsoft.Maui.IElement.set_Handler(IElementHandler value)
   at Microsoft.Maui.Platform.ElementExtensions.ToHandler(IElement view, IMauiContext context)
   at Microsoft.Maui.Platform.ViewExtensions.ToHandler(IView view, IMauiContext context)
   at Microsoft.Maui.Controls.Platform.Compatibility.ShellContentFragment.OnCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
   at AndroidX.Fragment.App.Fragment.n_OnCreateView_Landroid_view_LayoutInflater_Landroid_view_ViewGroup_Landroid_os_Bundle_(IntPtr jnienv, IntPtr native__this, IntPtr native_inflater, IntPtr native_container, IntPtr native_savedInstanceState)
   at Android.Runtime.JNINativeWrapper.Wrap_JniMarshal_PPLLL_L(_JniMarshal_PPLLL_L callback, IntPtr jnienv, IntPtr klazz, IntPtr p0, IntPtr p1, IntPtr p2)
	at crc640ec207abc449b2ca.ShellContentFragment.n_onCreateView(Native Method)
	at crc640ec207abc449b2ca.ShellContentFragment.onCreateView(ShellContentFragment.java:62)
	at androidx.fragment.app.Fragment.performCreateView(Fragment.java:3104)
	at androidx.fragment.app.FragmentStateManager.createView(FragmentStateManager.java:524)
	at androidx.fragment.app.FragmentStateManager.moveToExpectedState(FragmentStateManager.java:261)
	at androidx.fragment.app.FragmentManager.executeOpsTogether(FragmentManager.java:1890)
	at androidx.fragment.app.FragmentManager.removeRedundantOperationsAndExecute(FragmentManager.java:1808)
	at androidx.fragment.app.FragmentManager.execPendingActions(FragmentManager.java:1751)
	at androidx.fragment.app.FragmentManager$5.run(FragmentManager.java:538)
	at android.os.Handler.handleCallback(Handler.java:942)
	at android.os.Handler.dispatchMessage(Handler.java:99)
	at android.os.Looper.loopOnce(Looper.java:201)
	at android.os.Looper.loop(Looper.java:288)
	at android.app.ActivityThread.main(ActivityThread.java:7892)
	at java.lang.reflect.Method.invoke(Native Method)
	at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:548)
	at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:936)

Issue Analytics

State:
Created 10 months ago
Reactions:2
Comments:7 (1 by maintainers)

Top GitHub Comments

1reaction

espenrlcommented, Dec 20, 2022

This fixes it for me until it is patched. Based on #12141

           .ConfigureMauiHandlers(handlers =>
            {
#if ANDROID
                handlers.AddHandler(typeof(IndicatorView), typeof(FixCrashIndicatorViewHandler));
#endif
            })

/// <summary>
/// https://github.com/dotnet/maui/pull/12141
/// </summary>
public sealed class FixCrashIndicatorViewHandler : ViewHandler<IIndicatorView, MauiPageControl>, IIndicatorViewHandler
{
    public static readonly IPropertyMapper<IIndicatorView, IIndicatorViewHandler> Mapper = new PropertyMapper<IIndicatorView, IIndicatorViewHandler>(ViewMapper)
    {
        [nameof(IIndicatorView.Count)] = MapCount,
        [nameof(IIndicatorView.Position)] = MapPosition,
        [nameof(IIndicatorView.HideSingle)] = MapHideSingle,
        [nameof(IIndicatorView.MaximumVisible)] = MapMaximumVisible,
        [nameof(IIndicatorView.IndicatorSize)] = MapIndicatorSize,
        [nameof(IIndicatorView.IndicatorColor)] = MapIndicatorColor,
        [nameof(IIndicatorView.SelectedIndicatorColor)] = MapSelectedIndicatorColor,
        [nameof(IIndicatorView.IndicatorsShape)] = MapIndicatorShape
    };

    public static readonly CommandMapper<IIndicatorView, IIndicatorViewHandler> CommandMapper = new(ViewCommandMapper)
    {
    };

    public FixCrashIndicatorViewHandler() : base(Mapper)
    {
    }

    public FixCrashIndicatorViewHandler(IPropertyMapper? mapper)
        : base(mapper ?? Mapper, CommandMapper)
    {
    }

    public FixCrashIndicatorViewHandler(IPropertyMapper? mapper, CommandMapper? commandMapper)
        : base(mapper ?? Mapper, commandMapper ?? CommandMapper)
    {
    }

    IIndicatorView IIndicatorViewHandler.VirtualView => VirtualView;

    MauiPageControl IIndicatorViewHandler.PlatformView => PlatformView;

    protected override MauiPageControl CreatePlatformView()
    {
        return new MauiPageControl(Context);
    }

    protected override void ConnectHandler(MauiPageControl platformView)
    {
        base.ConnectHandler(platformView);

        if (platformView is MauiPageControl pageControl)
            pageControl.SetIndicatorView(VirtualView);
    }

    protected override void DisconnectHandler(MauiPageControl platformView)
    {
        base.DisconnectHandler(platformView);

        if (platformView is MauiPageControl pageControl)
            pageControl.SetIndicatorView(null);
    }

    public static void MapCount(IIndicatorViewHandler handler, IIndicatorView indicator)
    {
        handler.PlatformView.UpdateIndicatorCount();
    }

    public static void MapPosition(IIndicatorViewHandler handler, IIndicatorView indicator)
    {
        handler.PlatformView.UpdatePosition();
    }

    public static void MapHideSingle(IIndicatorViewHandler handler, IIndicatorView indicator)
    {
        handler.PlatformView.UpdateIndicatorCount();
    }

    public static void MapMaximumVisible(IIndicatorViewHandler handler, IIndicatorView indicator)
    {
        handler.PlatformView.UpdateIndicatorCount();
    }

    public static void MapIndicatorSize(IIndicatorViewHandler handler, IIndicatorView indicator)
    {
        handler.PlatformView.ResetIndicators();
    }

    public static void MapIndicatorColor(IIndicatorViewHandler handler, IIndicatorView indicator)
    {
        handler.PlatformView.ResetIndicators();
    }

    public static void MapSelectedIndicatorColor(IIndicatorViewHandler handler, IIndicatorView indicator)
    {
        handler.PlatformView.ResetIndicators();
    }

    public static void MapIndicatorShape(IIndicatorViewHandler handler, IIndicatorView indicator)
    {
        handler.PlatformView.ResetIndicators();
    }
}

0reactions

Kremedcommented, Dec 31, 2022

This fixes it for me until it is patched. Based on #12141

           .ConfigureMauiHandlers(handlers =>
            {
#if ANDROID
                handlers.AddHandler(typeof(IndicatorView), typeof(FixCrashIndicatorViewHandler));
#endif
            }) ```

Works Great For Me

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