Description

The android application experiences a crash when a user attempts to navigate back (i.e. removing the page from the stack) while a scroll animation is in progress and the ScrollViewHandler has been disconnected.

Here are three suggested improvements:

1. Refine the RequestScrollTo CommandMapping by adding a null-check for the VirtualView within the OnFinish Action Callback. This will prevent potential null reference errors.

2. Prior to disposing of the ScrollView from the ScrollViewHandler.DisconnectHandler, cancel the _scrollCompletionSource. This will ensure that no tasks are left open, improving resource management.

3. Create a publicly (or protected) accessible method to cancel the ScrollView Scroll animation task. This will provide greater flexibility and control over the Scroll animation.

Steps to Reproduce

1. Clone the reproduction project repository
2. Run on Android device
3. Navigate to Second Page
4. On Appearing of Second Page navigate back to main page (before scroll animation finishes)
5. App will crash

Link to public reproduction project repository

https://github.com/PATRICKdallat/ScrollViewHandlerCrash

Version with bug

8.0.10 SR3

Is this a regression from previous behavior?

No, this is something new

Last version that worked well

Unknown/Other

Affected platforms

Android

Affected platform versions

No response

Did you find any workaround?

Replacing the CommandMapper for IScrollView.RequestScrollTo

` ScrollViewHandler.CommandMapper.ReplaceMapping<IScrollView, ScrollViewHandler>(nameof(IScrollView.RequestScrollTo), (handler, _, args) =>
{
var context = handler.PlatformView.Context;

        if (args is not ScrollToRequest request || context is null)
        {
            return;
        }
    
        var horizontalOffsetDevice = (int)context.ToPixels(request.HorizontalOffset);
        var verticalOffsetDevice = (int)context.ToPixels(request.VerticalOffset);
    
        handler.PlatformView.ScrollTo(horizontalOffsetDevice, verticalOffsetDevice,
            request.Instant, () => handler?.VirtualView?.ScrollFinished());
    });`

Relevant log output

Android.Runtime.RuntimeNativeMethods.monodroid_debugger_unhandled_exception (Unknown Source:0) Android.Runtime.JNINativeWrapper._unhandled_exception (JNINativeWrapper.g.cs:13) Android.Runtime.JNINativeWrapper.Wrap_JniMarshal_PPL_V (JNINativeWrapper.g.cs:126) Microsoft.Maui.Handlers.ViewHandler<Microsoft.Maui.IScrollView,Microsoft.Maui.Platform.MauiScrollView>.get_VirtualView (ViewHandlerOfT.cs:42) Microsoft.Maui.Handlers.ScrollViewHandler.Microsoft.Maui.Handlers.IScrollViewHandler.get_VirtualView (ScrollViewHandler.cs:53) Microsoft.Maui.Handlers.ScrollViewHandler. (ScrollViewHandler.Android.cs:150) Microsoft.Maui.Platform.MauiScrollView. (MauiScrollView.cs:288) Android.Animation.AnimatorEventDispatcher.OnAnimationEnd (Animator.cs:86) Android.Animation.Animator.IAnimatorListenerInvoker.n_OnAnimationEnd_Landroid_animation_Animator_ (Android.Animation.Animator.cs:142) Android.Runtime.JNINativeWrapper.Wrap_JniMarshal_PPL_V (JNINativeWrapper.g.cs:125)