Xamarin.forms: Resetting MainPage causes blank screen to render

[brianlagunas]

Description

When you set the Application.MainPage to an instance of a TabbedPage that has a ContentPage on it's Modal nav stack, a blank screen is shown and the ContentPage is no longer on the TabbedPage's modal nav stack after the MainPage property is set. The hardware back button will then close the app.

Steps to Reproduce

1. Run the repro app in an emulator
2. Click the Rest button on ViewA
3. Review the code comments to step through and observe the values
4. Observe the blank screen in the emulator

Offending code

        private void _button_Clicked(object sender, EventArgs e)
        {
            //build up navigation stack
            var tabbedPage = new TabbedPage();
            tabbedPage.Navigation.PushModalAsync(new ViewB());

            //shoud have 1, this is correct
            var numberOfPages = tabbedPage.Navigation.ModalStack.Count;

            //reset main page - ViewB should be showing, but it's a blank screen
            App.Current.MainPage = tabbedPage;

            //should have 1 page on modal stack as before, but now there is 0
            numberOfPages = tabbedPage.Navigation.ModalStack.Count;
        }

Expected Behavior

ViewB should be correctly added to the TabbedPage's modal nav stack and rendered on the emulator. When the hardware back button is click, the TabbedPage should now be shown and ViewB should be popped off the stack.

Actual Behavior

A blank screen is show

Basic Information

• Version with issue: 2.5.0.280555
• Last known good version: NA
• IDE: VS 2017
• Platform Target Frameworks:
  
  
  
  • iOS:
  
  
  • Android:
  
  
  • UWP:
  
  
• Nuget Packages: Xamarin.Forms and it's dependencies

Screenshots

App launch

Button Click

Reproduction Link

https://github.com/brianlagunas/MainPageToTabbedPageIssue

[hartez]

Looks like setting the MainPage isn't bringing in the new page's modal stack; if you call tabbedPage.Navigation.PushModalAsync(new ViewB()); _after_ setting the MainPage, it works fine.

[brianlagunas]

To give full context, this is the process that the Prism navigation service takes to build up the navigation stack during a deep link. I will not be able to change the order in which the stack is built, as the entire Prism navigation is built on top of building up the nav stack prior to setting the MainPage.

[hartez]

@brianlagunas I didn't mean to suggest that you should change anything - I was just adding some info for whoever gets assigned this issue. AFAICT, what you're doing _should_ work just fine.

[brianlagunas]

@hartez Thanks for the update. I was not trying to imply that was your suggestion. I just wanted to give the full context of how the bug was found and the use case surrounding it, just incase "change the way you're doing it" would be suggested later in the conversation. Thank you for looking into this so quickly.

[JoeDurand3]

Does this need to be retested? I can confirm this is still an issue.

[dannypease]

Yes this is still an issue, and quite an important issue when it comes to trying to navigate to a certain page via a push notification for example. Is there a work around at all as I am trying to navigate in the following way:

await _navigationService.NavigateAsync("/TabbedPage?selectedTab=MiddleTab/Page1/Page2");

[KSemenenko]

I have the same issue with NavigationPage, any updates?

[vincentcastagna]

Can confirm this is still an issue that I meet too.

[MitchBomcanhao]

i'm running into a similar problem.

App launches and the screen is switched off during launch
App sets a loading page as the MainPage.
as part of displaying that loading page, we run a bit of code to determine where the app should go next.
It may decide to open a masterDetail list page, so it creates it and sets it to MainPage.

the user then switches the screen back on.

scenario a)
I don't use Device.BeginInvokeOnMainThread when setting these main pages

The app gets stuck on the loading page, even if the code has actually set the mainpage to be the masterdetail page.

scenario b)
I use Device.BeginInvokeOnMainThread when setting mainPage.

the app shows a blank screen instead of the expected masterdetail page.

if the screen is on whilst the app launches, there are no issues.

[Digi59404]

Can confirm - I'm also experiencing this issue.

[husseinmohkhalil]

I am facing the same too. still no workaround?

[KSemenenko]

the same on XF 4.3, 4.4

[almirvuk]

Hi, any news about this one? This is a really big issue for devs who want to build and URI for Prism navigation service which will open some details page from TabbedPage. The real and best usage is when the push notification is received and we want to navigate to a specific page as @dannypease already mentioned.

[RedasP]

the same on XF 4.3, 4.4

What exact version of 4.4 did you use?
I get this issue on 4.3.0.991250, but not on 4.4.0.991757

[KSemenenko]

I also have such a problem.
And I think this is a problem with the big page constructor.
the page is created on the UI thread and if it takes a long time, the application may stick.

[almirvuk]

@KSemenenko did you try it with 4.4.0.991757 as @RedasP mentioned?

[almirvuk]

Can we please, get more attention to this one for the next release? @samhouts

[dansiegel]

FWIW... this actually affects Hot Reload... as I've been experiencing this when making changes on my initial screen... this really does need some prioritization.

[samhouts]

Yep, this is coming back for sprint 168. Thanks for your patience, friends!

[kingces95]

I'm seeing this exception when I update to the latest v4. We're investigating but if anyone has an updated reproduction that'd be appreciated.

System.TypeLoadException: 'Could not resolve type with token 01000032 from typeref (expected class 'Xamarin.Forms.Xaml.XamlResourceIdAttribute' in assembly 'Xamarin.Forms.Core, Version=2.0.0.0, Culture=neutral, PublicKeyToken=null')'

[kingces95]

Looks like setting the MainPage isn't bringing in the new page's modal stack; if you call tabbedPage.Navigation.PushModalAsync(new ViewB()); after setting the MainPage, it works fine.

Hm, well, it doesn't work on iOS. And even on Android I see the animation. I assume we don't want to see the animation?

[kingces95]

After a model has been pushed another page or another model page can be pushed. In this way a stack of partitioned pages is built with each partition after the first representing a model push. For this feature to work generally, we'd have at allow them to generate this partitioned stack to an arbitrary depth.

Internally we represent this as a list of list with the bottom of the stack being [0][0]. See _stack. We have yet another stack that we only push the pages that begin a partition. See _modelStack.

That's a lot of lists, Jason. Next time, how about a Stack<Frame<Page>> where Frame is a struct with a boolean to track if the page starts a model partition? That would make the accounting for pushes and pops much simpler. I guess there's a reason...

PopToRoot takes a page that we use to find a partition and then pops frames within a model partition to that page. Odd. Who ordered that? Why break the stack abstraction? Similarly, Push allows for pushing a page onto any of the model partitions. Also odd for the same reason. I suppose that's the reason for all the lists... Still. who ordered that functionality?

[kingces95]

Well, this change makes the reproduction work. It's kinda of a stab in the dark. Basically, when assigning the NavigationProxy to Inner that's when the new main page starts reporting its stack to the application. Trouble with the way we had it, the page hasn't yet been crowned the new main page!

So the fix is: first, crown the main page, then have it report its stack of pages.

Who knows, maybe I'll just pass tests and I can go back to stressing about coronavirus. Doubt it'll be this simple tho.

[samhouts]

I wonder if the null check still needs to be there? Who sets their MainPage to null, though?

[almirvuk]

Any news about this one? 🙂

[AmrAlSayed0]

I have some update on this issue. I tried to reproduce it with a minimal repo with Xamarin.Forms 4.8.0.1451 but instead of a blank screen I get a Xamarin.Forms.InvalidNavigationException: Ancestor must be provided for all pushes except first.

Here is a minimal repo
Issues2562.zip
Here is a full stack trace

**Xamarin.Forms.InvalidNavigationException:** 'Ancestor must be provided for all pushes except first'
=================================================================
    Native Crash Reporting
=================================================================
Got a SEGV while executing native code. This usually indicates
a fatal error in the mono runtime or one of the native libraries
used by your application.
=================================================================

No native Android stacktrace (see debuggerd output).

=================================================================
    Basic Fault Address Reporting
=================================================================
Memory around native instruction pointer (0xeb54ac7c):
0xeb54ac6c  00 00 8b 0e 8b 80 18 01 00 00 8b 80 b8 00 00 00  ................
0xeb54ac7c  8b 49 40 f7 c1 00 00 04 00 0f 85 46 01 00 00 8b  [email protected]....
0xeb54ac8c  46 04 8a 4d 10 a9 00 00 04 00 0f 85 49 01 00 00  F..M........I...
0xeb54ac9c  8b 06 8b 40 10 89 44 24 08 0f b6 c9 8d 54 24 08  [email protected]$.....T$.

=================================================================
    Managed Stacktrace:
=================================================================
      at <unknown> <0xffffffff>
      at Java.Interop.NativeMethods:java_interop_jnienv_new_string <0x00012>
      at Strings:NewString <0x00077>
      at Strings:NewString <0x00147>
      at Android.Runtime.JNIEnv:NewString <0x0008f>
      at Java.Lang.Error:.ctor <0x000ff>
      at Android.Runtime.JavaProxyThrowable:.ctor <0x00067>
      at Java.Lang.Throwable:FromException <0x0012f>
      at Android.Runtime.AndroidEnvironment:UnhandledException <0x0030b>
      at Android.Runtime.DynamicMethodNameCounter:20 <0x00153>
      at Android.Runtime.DynamicMethodNameCounter:20 <0x000b3>
      at <unknown> <0xffffffff>
      at Java.Interop.NativeMethods:java_interop_jnienv_call_nonvirtual_boolean_method_a <0x00015>
      at InstanceMethods:CallNonvirtualBooleanMethod <0x00353>
      at JniInstanceMethods:InvokeVirtualBooleanMethod <0x002ef>
      at Android.Views.View:DispatchTouchEvent <0x00183>
      at Xamarin.Forms.Platform.Android.VisualElementRenderer`1:DispatchTouchEvent <0x000db>
      at DefaultRenderer:DispatchTouchEvent <0x00067>
      at Android.Views.View:n_DispatchTouchEvent_Landroid_view_MotionEvent_ <0x000ab>
      at Android.Runtime.DynamicMethodNameCounter:17 <0x000c7>
      at Android.Runtime.DynamicMethodNameCounter:17 <0x000b3>
      at <unknown> <0xffffffff>
      at Java.Interop.NativeMethods:java_interop_jnienv_call_nonvirtual_boolean_method_a <0x00015>
      at InstanceMethods:CallNonvirtualBooleanMethod <0x00353>
      at JniInstanceMethods:InvokeVirtualBooleanMethod <0x002ef>
      at Android.Views.View:DispatchTouchEvent <0x00183>
      at Xamarin.Forms.Platform.Android.VisualElementRenderer`1:DispatchTouchEvent <0x000db>
      at Android.Views.View:n_DispatchTouchEvent_Landroid_view_MotionEvent_ <0x000ab>
      at Android.Runtime.DynamicMethodNameCounter:17 <0x000c7>
      at Android.Runtime.DynamicMethodNameCounter:17 <0x000b3>
      at <unknown> <0xffffffff>
      at Java.Interop.NativeMethods:java_interop_jnienv_call_nonvirtual_boolean_method_a <0x00015>
      at InstanceMethods:CallNonvirtualBooleanMethod <0x00353>
      at JniInstanceMethods:InvokeVirtualBooleanMethod <0x002ef>
      at Android.Views.View:DispatchTouchEvent <0x00183>
      at Xamarin.Forms.Platform.Android.PlatformRenderer:DispatchTouchEvent <0x002fb>
      at Android.Views.View:n_DispatchTouchEvent_Landroid_view_MotionEvent_ <0x000ab>
      at Android.Runtime.DynamicMethodNameCounter:17 <0x000c7>
      at Android.Runtime.DynamicMethodNameCounter:17 <0x000b3>
=================================================================

10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570] JNI DETECTED ERROR IN APPLICATION: JNI NewString called with pending exception android.runtime.JavaProxyThrowable: Xamarin.Forms.InvalidNavigationException: Ancestor must be provided for all pushes except first
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at Xamarin.Forms.Internals.NavigationModel.Push (Xamarin.Forms.Page page, Xamarin.Forms.Page ancestralNav) [0x00010] in D:\a\1\s\Xamarin.Forms.Core\NavigationModel.cs:134 
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at Xamarin.Forms.Platform.Android.AppCompat.Platform.SetPageInternal (Xamarin.Forms.Page newRoot) [0x00046] in D:\a\1\s\Xamarin.Forms.Platform.Android\AppCompat\Platform.cs:337
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at Xamarin.Forms.Platform.Android.AppCompat.Platform.SetPage (Xamarin.Forms.Page newRoot) [0x000d6] in D:\a\1\s\Xamarin.Forms.Platform.Android\AppCompat\Platform.cs:289
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at Xamarin.Forms.Platform.Android.FormsAppCompatActivity.InternalSetPage (Xamarin.Forms.Page page) [0x0001a] in D:\a\1\s\Xamarin.Forms.Platform.Android\AppCompat\FormsAppCompatActivity.cs:510 
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at Xamarin.Forms.Platform.Android.FormsAppCompatActivity.SetMainPage () [0x00000] in D:\a\1\s\Xamarin.Forms.Platform.Android\AppCompat\FormsAppCompatActivity.cs:543 
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at Xamarin.Forms.Platform.Android.FormsAppCompatActivity.AppOnPropertyChanged (System.Object sender, System.ComponentModel.PropertyChangedEventArgs args) [0x00035] in D:\a\1\s\Xamarin.Forms.Platform.Android\AppCompat\FormsAppCompatActivity.cs:473 
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at Xamarin.Forms.BindableObject.OnPropertyChanged (System.String propertyName) [0x00000] in D:\a\1\s\Xamarin.Forms.Core\BindableObject.cs:229 
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at Xamarin.Forms.Element.OnPropertyChanged (System.String propertyName) [0x00000] in D:\a\1\s\Xamarin.Forms.Core\Element.cs:358 
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at Xamarin.Forms.Application.set_MainPage (Xamarin.Forms.Page value) [0x0008b] in D:\a\1\s\Xamarin.Forms.Core\Application.cs:93 
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at CleanXamarinFormsApp.MainPage.TapGestureRecognizer_Tapped (System.Object sender, System.EventArgs e) [0x00029] in C:\Repos\Issues2562\CleanXamarinFormsApp\CleanXamarinFormsApp\MainPage.xaml.cs:31 
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at Xamarin.Forms.TapGestureRecognizer.SendTapped (Xamarin.Forms.View sender) [0x0002e] in D:\a\1\s\Xamarin.Forms.Core\TapGestureRecognizer.cs:48 
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at Xamarin.Forms.Platform.Android.TapGestureHandler.OnTap (System.Int32 count, Xamarin.Forms.Point point) [0x000a2] in D:\a\1\s\Xamarin.Forms.Platform.Android\TapGestureHandler.cs:52 
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at Xamarin.Forms.Platform.Android.InnerGestureListener.Android.Views.GestureDetector.IOnGestureListener.OnSingleTapUp (Android.Views.MotionEvent e) [0x00014] in D:\a\1\s\Xamarin.Forms.Platform.Android\InnerGestureListener.cs:151 
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at Android.Views.GestureDetector+IOnGestureListenerInvoker.n_OnSingleTapUp_Landroid_view_MotionEvent_ (System.IntPtr jnienv, System.IntPtr native__this, System.IntPtr native_e) [0x0000f] in <a4bd551a8605435ba108e51ba9322d09>:0 
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at (wrapper dynamic-method) Android.Runtime.DynamicMethodNameCounter.39(intptr,intptr,intptr)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at boolean crc643f46942d9dd1fff9.InnerGestureListener.n_onSingleTapUp(android.view.MotionEvent) (InnerGestureListener.java:-2)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at boolean crc643f46942d9dd1fff9.InnerGestureListener.onSingleTapUp(android.view.MotionEvent) (InnerGestureListener.java:79)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at boolean android.view.GestureDetector.onTouchEvent(android.view.MotionEvent) (GestureDetector.java:730)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at boolean crc64ee486da937c010f4.LabelRenderer.n_onTouchEvent(android.view.MotionEvent) (LabelRenderer.java:-2)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at boolean crc64ee486da937c010f4.LabelRenderer.onTouchEvent(android.view.MotionEvent) (LabelRenderer.java:62)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at boolean android.view.View.dispatchTouchEvent(android.view.MotionEvent) (View.java:13415)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at boolean android.view.ViewGroup.dispatchTransformedTouchEvent(android.view.MotionEvent, boolean, android.view.View, int) (ViewGroup.java:3060)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at boolean android.view.ViewGroup.dispatchTouchEvent(android.view.MotionEvent) (ViewGroup.java:2755)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at boolean crc643f46942d9dd1fff9.Platform_DefaultRenderer.n_dispatchTouchEvent(android.view.MotionEvent) (Platform_DefaultRenderer.java:-2)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at boolean crc643f46942d9dd1fff9.Platform_DefaultRenderer.dispatchTouchEvent(android.view.MotionEvent) (Platform_DefaultRenderer.java:56)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at boolean android.view.ViewGroup.dispatchTransformedTouchEvent(android.view.MotionEvent, boolean, android.view.View, int) (ViewGroup.java:3060)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at boolean android.view.ViewGroup.dispatchTouchEvent(android.view.MotionEvent) (ViewGroup.java:2755)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at boolean crc643f46942d9dd1fff9.VisualElementRenderer_1.n_dispatchTouchEvent(android.view.MotionEvent) (VisualElementRenderer_1.java:-2)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at boolean crc643f46942d9dd1fff9.VisualElementRenderer_1.dispatchTouchEvent(android.view.MotionEvent) (VisualElementRenderer_1.java:67)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at boolean android.view.ViewGroup.dispatchTransformedTouchEvent(android.view.MotionEvent, boolean, android.view.View, int) (ViewGroup.java:3060)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at boolean android.view.ViewGroup.dispatchTouchEvent(android.view.MotionEvent) (ViewGroup.java:2755)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at boolean crc643f46942d9dd1fff9.PlatformRenderer.n_dispatchTouchEvent(android.view.MotionEvent) (PlatformRenderer.java:-2)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at boolean crc643f46942d9dd1fff9.PlatformRenderer.dispatchTouchEvent(android.view.MotionEvent) (PlatformRenderer.java:55)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at boolean android.view.ViewGroup.dispatchTransformedTouchEvent(android.view.MotionEvent, boolean, android.view.View, int) (ViewGroup.java:3060)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at boolean android.view.ViewGroup.dispatchTouchEvent(android.view.MotionEvent) (ViewGroup.java:2755)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at boolean android.view.ViewGroup.dispatchTransformedTouchEvent(android.view.MotionEvent, boolean, android.view.View, int) (ViewGroup.java:3060)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at boolean android.view.ViewGroup.dispatchTouchEvent(android.view.MotionEvent) (ViewGroup.java:2755)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at boolean android.view.ViewGroup.dispatchTransformedTouchEvent(android.view.MotionEvent, boolean, android.view.View, int) (ViewGroup.java:3060)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at boolean android.view.ViewGroup.dispatchTouchEvent(android.view.MotionEvent) (ViewGroup.java:2755)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at boolean android.view.ViewGroup.dispatchTransformedTouchEvent(android.view.MotionEvent, boolean, android.view.View, int) (ViewGroup.java:3060)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at boolean android.view.ViewGroup.dispatchTouchEvent(android.view.MotionEvent) (ViewGroup.java:2755)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at boolean android.view.ViewGroup.dispatchTransformedTouchEvent(android.view.MotionEvent, boolean, android.view.View, int) (ViewGroup.java:3060)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at boolean android.view.ViewGroup.dispatchTouchEvent(android.view.MotionEvent) (ViewGroup.java:2755)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at boolean android.view.ViewGroup.dispatchTransformedTouchEvent(android.view.MotionEvent, boolean, android.view.View, int) (ViewGroup.java:3060)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at boolean android.view.ViewGroup.dispatchTouchEvent(android.view.MotionEvent) (ViewGroup.java:2755)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at boolean com.android.internal.policy.DecorView.superDispatchTouchEvent(android.view.MotionEvent) (DecorView.java:465)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at boolean com.android.internal.policy.PhoneWindow.superDispatchTouchEvent(android.view.MotionEvent) (PhoneWindow.java:1849)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at boolean android.app.Activity.dispatchTouchEvent(android.view.MotionEvent) (Activity.java:3993)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at boolean androidx.appcompat.view.WindowCallbackWrapper.dispatchTouchEvent(android.view.MotionEvent) (WindowCallbackWrapper.java:69)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at boolean androidx.appcompat.view.WindowCallbackWrapper.dispatchTouchEvent(android.view.MotionEvent) (WindowCallbackWrapper.java:69)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at boolean com.android.internal.policy.DecorView.dispatchTouchEvent(android.view.MotionEvent) (DecorView.java:423)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at boolean android.view.View.dispatchPointerEvent(android.view.MotionEvent) (View.java:13674)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at int android.view.ViewRootImpl$ViewPostImeInputStage.processPointerEvent(android.view.ViewRootImpl$QueuedInputEvent) (ViewRootImpl.java:5482)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at int android.view.ViewRootImpl$ViewPostImeInputStage.onProcess(android.view.ViewRootImpl$QueuedInputEvent) (ViewRootImpl.java:5285)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at void android.view.ViewRootImpl$InputStage.deliver(android.view.ViewRootImpl$QueuedInputEvent) (ViewRootImpl.java:4788)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at void android.view.ViewRootImpl$InputStage.onDeliverToNext(android.view.ViewRootImpl$QueuedInputEvent) (ViewRootImpl.java:4841)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at void android.view.ViewRootImpl$InputStage.forward(android.view.ViewRootImpl$QueuedInputEvent) (ViewRootImpl.java:4807)
10-02 21:49:36.998 F/xamarinformsap(15980): java_vm_ext.cc:570]   at void android.view.ViewRootImpl$AsyncInputStage.forward(android.view.ViewRootImpl$QueuedInputEvent) (ViewRootImpl.java:4947)
10-02 21:49:36.999 F/xamarinformsap(15980): java_vm_ext.cc:570]   at void android.view.ViewRootImpl$InputStage.apply(android.view.ViewRootImpl$QueuedInputEvent, int) (ViewRootImpl.java:4815)
10-02 21:49:36.999 F/xamarinformsap(15980): java_vm_ext.cc:570]   at void android.view.ViewRootImpl$AsyncInputStage.apply(android.view.ViewRootImpl$QueuedInputEvent, int) (ViewRootImpl.java:5004)
10-02 21:49:36.999 F/xamarinformsap(15980): java_vm_ext.cc:570]   at void android.view.ViewRootImpl$InputStage.deliver(android.view.ViewRootImpl$QueuedInputEvent) (ViewRootImpl.java:4788)
10-02 21:49:36.999 F/xamarinformsap(15980): java_vm_ext.cc:570]   at void android.view.ViewRootImpl$InputStage.onDeliverToNext(android.view.ViewRootImpl$QueuedInputEvent) (ViewRootImpl.java:4841)
10-02 21:49:36.999 F/xamarinformsap(15980): java_vm_ext.cc:570]   at void android.view.ViewRootImpl$InputStage.forward(android.view.ViewRootImpl$QueuedInputEvent) (ViewRootImpl.java:4807)
10-02 21:49:36.999 F/xamarinformsap(15980): java_vm_ext.cc:570]   at void android.view.ViewRootImpl$InputStage.apply(android.view.ViewRootImpl$QueuedInputEvent, int) (ViewRootImpl.java:4815)
10-02 21:49:36.999 F/xamarinformsap(15980): java_vm_ext.cc:570]   at void android.view.ViewRootImpl$InputStage.deliver(android.view.ViewRootImpl$QueuedInputEvent) (ViewRootImpl.java:4788)
10-02 21:49:36.999 F/xamarinformsap(15980): java_vm_ext.cc:570]   at void android.view.ViewRootImpl.deliverInputEvent(android.view.ViewRootImpl$QueuedInputEvent) (ViewRootImpl.java:7505)
10-02 21:49:36.999 F/xamarinformsap(15980): java_vm_ext.cc:570]   at void android.view.ViewRootImpl.doProcessInputEvents() (ViewRootImpl.java:7474)
10-02 21:49:36.999 F/xamarinformsap(15980): java_vm_ext.cc:570]   at void android.view.ViewRootImpl.enqueueInputEvent(android.view.InputEvent, android.view.InputEventReceiver, int, boolean) (ViewRootImpl.java:7435)
10-02 21:49:36.999 F/xamarinformsap(15980): java_vm_ext.cc:570]   at void android.view.ViewRootImpl$WindowInputEventReceiver.onInputEvent(android.view.InputEvent) (ViewRootImpl.java:7630)
10-02 21:49:36.999 F/xamarinformsap(15980): java_vm_ext.cc:570]   at void android.view.InputEventReceiver.dispatchInputEvent(int, android.view.InputEvent) (InputEventReceiver.java:188)
10-02 21:49:36.999 F/xamarinformsap(15980): java_vm_ext.cc:570]   at void android.os.MessageQueue.nativePollOnce(long, int) (MessageQueue.java:-2)
10-02 21:49:36.999 F/xamarinformsap(15980): java_vm_ext.cc:570]   at android.os.Message android.os.MessageQueue.next() (MessageQueue.java:336)
10-02 21:49:36.999 F/xamarinformsap(15980): java_vm_ext.cc:570]   at void android.os.Looper.loop() (Looper.java:174)
10-02 21:49:36.999 F/xamarinformsap(15980): java_vm_ext.cc:570]   at void android.app.ActivityThread.main(java.lang.String[]) (ActivityThread.java:7356)
10-02 21:49:36.999 F/xamarinformsap(15980): java_vm_ext.cc:570]   at java.lang.Object java.lang.reflect.Method.invoke(java.lang.Object, java.lang.Object[]) (Method.java:-2)
10-02 21:49:36.999 F/xamarinformsap(15980): java_vm_ext.cc:570]   at void com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run() (RuntimeInit.java:492)
10-02 21:49:36.999 F/xamarinformsap(15980): java_vm_ext.cc:570]   at void com.android.internal.os.ZygoteInit.main(java.lang.String[]) (ZygoteInit.java:930)
10-02 21:49:36.999 F/xamarinformsap(15980): java_vm_ext.cc:570] 
10-02 21:49:36.999 F/xamarinformsap(15980): java_vm_ext.cc:570]     in call to NewString
10-02 21:49:36.999 F/xamarinformsap(15980): java_vm_ext.cc:570]     from boolean crc643f46942d9dd1fff9.InnerGestureListener.n_onSingleTapUp(android.view.MotionEvent)
10-02 21:49:37.004 F/libc    (15980): Fatal signal 11 (SIGSEGV), code 1 (SEGV_MAPERR), fault addr 0x40 in tid 15980 (xamarinformsapp), pid 15980 (xamarinformsapp)