Xamarin.forms: [Bug] In Android, Attempt to read from field 'int android.view.ViewGroup$LayoutParams.width' on a null object reference occurs with XF 4.3.0.991221

[GnanaPriyaNamasivayam]

Description

In SfAccordion (is only the view) while loading labels directly into the Template, the null reference exception occurs from native(Android). But this crash did not occur if I backtrack to XF 4.3.0.991211 and also if I load label/Entry inside Grid.

Steps to Reproduce

1. Run the sample in android

Edit

    <syncfusion:SfAccordion x:Name="Accordion" BindableLayout.ItemsSource="{Binding Info}">
        <BindableLayout.ItemTemplate>
            <DataTemplate>
                <syncfusion:AccordionItem>
                    <syncfusion:AccordionItem.Header>
                            **<Label Text="{Binding Name}"/>**  // When label directly loaded inside Header/content -crash occurs(If i wrap label inside grid then it works fine.)
                    </syncfusion:AccordionItem.Header>
                    <syncfusion:AccordionItem.Content>
                            <Label Text="{Binding Description}"/>
                    </syncfusion:AccordionItem.Content>
                </syncfusion:AccordionItem>
            </DataTemplate>
        </BindableLayout.ItemTemplate>

Note: While loading a crash will occur.
For Label: Attempt to read from field int android.view.viewGroup$LayoutParams.width
For Entry : Can't resolve the reference 'System.Drawing.RectangleF System.Drawing.RectangleF::Empty', referenced from the method 'UIKit.UITextField Xamarin.Forms.Platform.iOS.EntryRenderer::CreateNativeControl()' in 'System.Drawing.Common

Expected Behavior

In XF 4.3.0.991221, an application should load properly without the null reference even if label loaded directly inside Accordion Itemtemplate.

Actual Behavior

App crashes with null reference exception while loading in android.

Basic Information

• Version with issue:
• Last known good version: 4.3.0.991211
• Platform Target Frameworks:
  
  
  
  • Android: 7.0, 9.0
    
    

    Reproduction Link

  
  

https://www.syncfusion.com/downloads/support/directtrac/general/ze/Accordion1198327037

[kingces95]

After updating the nuget packages I'm able to load the android project. Please update the nuget packages and reattach/repost the reproduction if you're still seeing a crash.

[GnanaPriyaNamasivayam]

We still face the crash with the below exception. Last good known version is XF 4.3.0.991211

Sample: https://www.syncfusion.com/downloads/support/directtrac/general/ze/Accordion1194689223
0xFFFFFFFFFFFFFFFF in System.Diagnostics.Debugger.Mono_UnhandledException_internal C#
0x1 in System.Diagnostics.Debugger.Mono_UnhandledException C#
0x26 in object.7 C#
0x12 in System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw C#
0x89 in Java.Interop.JniEnvironment.InstanceMethods.CallNonvirtualVoidMethod C#
0x21 in Java.Interop.JniPeerMembers.JniInstanceMethods.InvokeNonvirtualVoidMethod C#
0x30 in Android.Widget.TextView.set_HintFormatted C#
0xF in Android.Widget.TextView.set_Hint C#
0x161 in Xamarin.Forms.Platform.Android.FastRenderers.LabelRenderer.Xamarin.Forms.Platform.Android.IVisualElementRenderer.GetDesiredSize at D:\a\1\s\Xamarin.Forms.Platform.Android\FastRenderersLabelRenderer.cs:127,4 C#
0xB3 in Xamarin.Forms.Platform.Android.Platform.GetNativeSize at D:\a\1\s\Xamarin.Forms.Platform.Android\Platform.cs:1332,4 C#
0x3 in Xamarin.Forms.Forms.AndroidPlatformServices.GetNativeSize at D:\a\1\s\Xamarin.Forms.Platform.Android\Forms.cs:776,5 C#
0x2D in Xamarin.Forms.VisualElement.OnSizeRequest at D:\a\1\s\Xamarin.Forms.Core\VisualElement.cs:779,4 C#
0x3 in Xamarin.Forms.VisualElement.OnMeasure at D:\a\1\s\Xamarin.Forms.Core\VisualElement.cs:762,4 C#
0x56 in Xamarin.Forms.VisualElement.GetSizeRequest at D:\a\1\s\Xamarin.Forms.Core\VisualElement.cs:644,4 C#
0x57 in Xamarin.Forms.VisualElement.Measure at D:\a\1\s\Xamarin.Forms.Core\VisualElement.cs:702,4 C#
0x4F in Syncfusion.Platform.Mapping.CodeSharingHelper.CreateNativeView C#
0x7E in Syncfusion.XForms.Android.Accordion.AccordionRenderer.UpdateNativeAccordionItemProperties C#
0x42 in Syncfusion.XForms.Android.Accordion.AccordionRenderer.ConvertFormsToNativeAccordionItems C#
0x111 in Syncfusion.XForms.Android.Accordion.AccordionRenderer.OnElementChanged C#
0xC0 in Xamarin.Forms.Platform.Android.VisualElementRenderer.SetElement at D:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementRenderer.cs:231,4 C#
0x2E in Xamarin.Forms.Platform.Android.VisualElementRenderer.Xamarin.Forms.Platform.Android.IVisualElementRenderer.SetElement at D:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementRenderer.cs:128,4 C#
0x21 in Xamarin.Forms.Platform.Android.Platform.CreateRenderer at D:\a\1\s\Xamarin.Forms.Platform.Android\Platform.cs:344,4 C#
0xC0 in Xamarin.Forms.Platform.Android.VisualElementPackager.AddChild at D:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementPackager.cs:138,6 C#
0x14C in Xamarin.Forms.Platform.Android.VisualElementPackager.SetElement at D:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementPackager.cs:334,6 C#
0x8 in Xamarin.Forms.Platform.Android.VisualElementPackager.Load at D:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementPackager.cs:110,4 C#
0x8 in Xamarin.Forms.Platform.Android.VisualElementRenderer.SetPackager at D:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementRenderer.cs:440,4 C#
0xDD in Xamarin.Forms.Platform.Android.VisualElementRenderer.SetElement at D:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementRenderer.cs:234,5 C#
0x2E in Xamarin.Forms.Platform.Android.VisualElementRenderer.Xamarin.Forms.Platform.Android.IVisualElementRenderer.SetElement at D:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementRenderer.cs:128,4 C#
0x21 in Xamarin.Forms.Platform.Android.Platform.CreateRenderer at D:\a\1\s\Xamarin.Forms.Platform.Android\Platform.cs:344,4 C#
0x14 in Xamarin.Forms.Platform.Android.AppCompat.Platform.AddChild at D:\a\1\s\Xamarin.Forms.Platform.Android\AppCompat\Platform.cs:362,4 C#
0x3E in Xamarin.Forms.Platform.Android.AppCompat.Platform.SetPageInternal at D:\a\1\s\Xamarin.Forms.Platform.Android\AppCompat\Platform.cs:320,4 C#
0xDE in Xamarin.Forms.Platform.Android.AppCompat.Platform.SetPage at D:\a\1\s\Xamarin.Forms.Platform.Android\AppCompat\Platform.cs:282,5 C#
0x40 in Xamarin.Forms.Platform.Android.FormsAppCompatActivity.InternalSetPage at D:\a\1\s\Xamarin.Forms.Platform.Android\AppCompat\FormsAppCompatActivity.cs:439,4 C#
0xC in Xamarin.Forms.Platform.Android.FormsAppCompatActivity.SetMainPage at D:\a\1\s\Xamarin.Forms.Platform.Android\AppCompat\FormsAppCompatActivity.cs:465,4 C#
0x119 in Xamarin.Forms.Platform.Android.FormsAppCompatActivity.LoadApplication at D:\a\1\s\Xamarin.Forms.Platform.Android\AppCompat\FormsAppCompatActivity.cs:188,4 C#

0x2D in AccordionBindableLayout.Droid.MainActivity.OnCreate at D:\Incident\Expander\Accordion\AccordionBindableLayout\AccordionBindableLayout.Android\MainActivity.cs:22,13 C#
0x13 in Android.App.Activity.n_OnCreate_Landroid_os_Bundle_ C#

[asusralis]

I get this in 4.3.0.991211. I downgraded for a very similar issue that was fixed once I downgraded, but it seems a similar problem exists on this version as well.

0xFFFFFFFFFFFFFFFF in System.Diagnostics.Debugger.Mono_UnhandledException_internal
0x1 in System.Diagnostics.Debugger.Mono_UnhandledException at /Users/builder/jenkins/workspace/archive-mono/2019-08/android/release/mcs/class/corlib/System.Diagnostics/Debugger.cs:120,4
0x20 in Android.Runtime.DynamicMethodNameCounter.34
0x12 in System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw at /Users/builder/jenkins/workspace/archive-mono/2019-08/android/release/mcs/class/referencesource/mscorlib/system/runtime/exceptionservices/exceptionservicescommon.cs:157,13
0x8E in Java.Interop.JniEnvironment.InstanceMethods.CallNonvirtualVoidMethod
0x21 in Java.Interop.JniPeerMembers.JniInstanceMethods.InvokeNonvirtualVoidMethod
0x30 in Android.Widget.TextView.set_TextFormatted
0xF in Android.Widget.TextView.set_Text
0xFF in Xamarin.Forms.Platform.Android.FastRenderers.LabelRenderer.UpdateText at D:\a\1\s\Xamarin.Forms.Platform.Android\FastRenderersLabelRenderer.cs:398,7
0x124 in Xamarin.Forms.Platform.Android.FastRenderers.LabelRenderer.OnElementPropertyChanged at D:\a\1\s\Xamarin.Forms.Platform.Android\FastRenderersLabelRenderer.cs:279,5
0x12 in Xamarin.Forms.BindableObject.OnPropertyChanged at D:\a\1\s\Xamarin.Forms.Core\BindableObject.cs:229,7
0x2 in Xamarin.Forms.Element.OnPropertyChanged at D:\a\1\s\Xamarin.Forms.Core\Element.cs:350,4
0x11B in Xamarin.Forms.BindableObject.SetValueActual at D:\a\1\s\Xamarin.Forms.Core\BindableObject.cs:461,5
0x17C in Xamarin.Forms.BindableObject.SetValueCore at D:\a\1\s\Xamarin.Forms.Core\BindableObject.cs:397,5
0x227 in Xamarin.Forms.BindingExpression.ApplyCore at D:\a\1\s\Xamarin.Forms.Core\BindingExpression.cs:155,5
0x48 in Xamarin.Forms.BindingExpression.Apply at D:\a\1\s\Xamarin.Forms.Core\BindingExpression.cs:51,5
0x7 in Xamarin.Forms.BindingExpression.BindingExpressionPart.b__49_0 at D:\a\1\s\Xamarin.Forms.Core\BindingExpression.cs:705,27
0xE in Java.Lang.Thread.RunnableImplementor.Run
0xA in Java.Lang.IRunnableInvoker.n_Run
0x11 in Android.Runtime.DynamicMethodNameCounter.34

[samhouts]

@GnanaPriyaNamasivayam @asusralis Are you using VS 2017?

[asusralis]

@samhouts I'm on 2019 16.4.

[GnanaPriyaNamasivayam]

@samhouts , No. The issue occurs in VS 2019 still with Expander 17.4.0.40 & XF 4.4.0.991.265.

FYI.

[samhouts]

@GnanaPriyaNamasivayam Is there something special I need to do to cause the crash? I have loaded the project in VS 2019 for Mac, Stable channel, and VS 2019 for Windows, and it doesn't crash in either.

[GnanaPriyaNamasivayam]

@samhouts , Can you please check in any real-time android device with 9.0 or 7.0 version. I have checked Mi A, Moto G5. It occurs frequently when you load label directly inside header or content of Accordion without wrapping inside Grid.

[samhouts]

@GnanaPriyaNamasivayam Strange. I'm testing with a real OnePlus 3T API28 device, and it seems to work fine.

[GnanaPriyaNamasivayam]

Can you please confirm or share XAML that you load directly inside Accordion Content or Header. The issue occurs still on our side.

[samhouts]

@GnanaPriyaNamasivayam I'm running the provided project as is.

[GnanaPriyaNamasivayam]

@samhouts, Actual reason for this chaos - replication sample was attached with the workaround.

Re-attached sample: https://www.syncfusion.com/downloads/support/directtrac/general/ze/Accordion1491733448

[samhouts]

@GnanaPriyaNamasivayam That did the trick! This reproduces for me in the latest 4.4.0 service release, too. Thanks!

[mkieres]

This issue doesn't seem to be only related to SfAccordion.

I'm facing similar issue with SfChart as well. I'm attaching a repro sample, in which I'm adding a LabelTemplate to the ChartDataMarker with only a Label, which causes an exception with similar if not the same error message.

Stacktraces:

01-23 13:31:53.847 E/AppCenterCrashes(22375): Unhandled Exception from source=AndroidEnvironment
01-23 13:31:53.847 E/AppCenterCrashes(22375): Java.Lang.NullPointerException: Attempt to read from field 'int android.view.ViewGroup$LayoutParams.width' on a null object reference
01-23 13:31:53.847 E/AppCenterCrashes(22375):   at Java.Interop.JniEnvironment+InstanceMethods.CallNonvirtualVoidMethod (Java.Interop.JniObjectReference instance, Java.Interop.JniObjectReference type, Java.Interop.JniMethodInfo method, Java.Interop.JniArgumentValue* args) [0x0008e] in <f8a5ef81e6f64091812a7da2968fba8c>:0 
01-23 13:31:53.847 E/AppCenterCrashes(22375):   at Java.Interop.JniPeerMembers+JniInstanceMethods.InvokeNonvirtualVoidMethod (System.String encodedMember, Java.Interop.IJavaPeerable self, Java.Interop.JniArgumentValue* parameters) [0x0001f] in <f8a5ef81e6f64091812a7da2968fba8c>:0 
01-23 13:31:53.847 E/AppCenterCrashes(22375):   at Android.Widget.TextView.set_HintFormatted (Java.Lang.ICharSequence value) [0x00029] in <06692e0cad5848598a0f46942a89e99f>:0 
01-23 13:31:53.847 E/AppCenterCrashes(22375):   at Android.Widget.TextView.set_Hint (System.String value) [0x0000d] in <06692e0cad5848598a0f46942a89e99f>:0 
01-23 13:31:53.847 E/AppCenterCrashes(22375):   at Xamarin.Forms.Platform.Android.FastRenderers.LabelRenderer.Xamarin.Forms.Platform.Android.IVisualElementRenderer.GetDesiredSize (System.Int32 widthConstraint, System.Int32 heightConstraint) [0x0015a] in D:\a\1\s\Xamarin.Forms.Platform.Android\FastRenderers\LabelRenderer.cs:127 
01-23 13:31:53.847 E/AppCenterCrashes(22375):   at Xamarin.Forms.Platform.Android.Platform.GetNativeSize (Xamarin.Forms.VisualElement view, System.Double widthConstraint, System.Double heightConstraint) [0x000ae] in D:\a\1\s\Xamarin.Forms.Platform.Android\Platform.cs:1333 
01-23 13:31:53.847 E/AppCenterCrashes(22375):   at Xamarin.Forms.Forms+AndroidPlatformServices.GetNativeSize (Xamarin.Forms.VisualElement view, System.Double widthConstraint, System.Double heightConstraint) [0x00000] in D:\a\1\s\Xamarin.Forms.Platform.Android\Forms.cs:776 
01-23 13:31:53.847 E/AppCenterCrashes(22375):   at Xamarin.Forms.VisualElement.OnSizeRequest (System.Double widthConstraint, System.Double heightConstraint) [0x00025] in D:\a\1\s\Xamarin.Forms.Core\VisualElement.cs:779 
01-23 13:31:53.847 E/AppCenterCrashes(22375):   at Xamarin.Forms.VisualElement.OnMeasure (System.Double widthConstraint, System.Double heightConstraint) [0x00000] in D:\a\1\s\Xamarin.Forms.Core\VisualElement.cs:762 
01-23 13:31:53.847 E/AppCenterCrashes(22375):   at Xamarin.Forms.VisualElement.GetSizeRequest (System.Double widthConstraint, System.Double heightConstraint) [0x00053] in D:\a\1\s\Xamarin.Forms.Core\VisualElement.cs:644 
01-23 13:31:53.847 E/AppCenterCrashes(22375):   at Xamarin.Forms.VisualElement.Measure (System.Double widthConstraint, System.Double heightConstraint, Xamarin.Forms.MeasureFlags flags) [0x00054] in D:\a\1\s\Xamarin.Forms.Core\VisualElement.cs:702 
01-23 13:31:53.847 E/AppCenterCrashes(22375):   at Syncfusion.SfChart.XForms.Droid.SfChartRenderer.GetNativeView (System.Object bindingContext, Syncfusion.SfChart.XForms.SfChart formChart, Xamarin.Forms.View view, Android.Views.ViewGroup+LayoutParams layoutParams) [0x0001d] in <4a2670bfcbc849bea198cd3e499de357>:0 
01-23 13:31:53.847 E/AppCenterCrashes(22375):   at Syncfusion.SfChart.XForms.Droid.SfChartRenderer.GetNativeView (System.Object bindingContext, Syncfusion.SfChart.XForms.SfChart formChart, Xamarin.Forms.DataTemplate dataTemplate, Android.Views.ViewGroup+LayoutParams layoutParams) [0x0003f] in <4a2670bfcbc849bea198cd3e499de357>:0 
01-23 13:31:53.847 E/AppCenterCrashes(22375):   at Syncfusion.SfChart.XForms.Droid.ChartDataMarkerMapping.NativeSeries_DataMarkerLabelCreated (System.Object sender, Com.Syncfusion.Charts.ChartSeries+DataMarkerLabelCreatedEventArgs e) [0x00125] in <4a2670bfcbc849bea198cd3e499de357>:0 
01-23 13:31:53.847 E/AppCenterCrashes(22375):   at Com.Syncfusion.Charts.ChartSeries.OnDataMarkerLabelCreated (Com.Syncfusion.Charts.DataMarkerLabel dataMarkerLabel) [0x0007f] in <4a2670bfcbc849bea198cd3e499de357>:0 
01-23 13:31:53.847 E/AppCenterCrashes(22375):   at Com.Syncfusion.Charts.XyDataSeries.CreateDataMarkerLabels () [0x0035f] in <4a2670bfcbc849bea198cd3e499de357>:0 
01-23 13:31:53.847 E/AppCenterCrashes(22375):   at Com.Syncfusion.Charts.ChartBase.UpdateArea () [0x00157] in <4a2670bfcbc849bea198cd3e499de357>:0 
01-23 13:31:53.847 E/AppCenterCrashes(22375):   at Com.Syncfusion.Charts.ChartBase.OnMeasureChart () [0x00031] in <4a2670bfcbc849bea198cd3e499de357>:0 
01-23 13:31:53.847 E/AppCenterCrashes(22375):   at Com.Syncfusion.Charts.SfChart.OnMeasure (System.Int32 widthMeasureSpec, System.Int32 heightMeasureSpec) [0x001f4] in <4a2670bfcbc849bea198cd3e499de357>:0 
01-23 13:31:53.847 E/AppCenterCrashes(22375):   at Android.Views.View.n_OnMeasure_II (System.IntPtr jnienv, System.IntPtr native__this, System.Int32 widthMeasureSpec, System.Int32 heightMeasureSpec) [0x00009] in <06692e0cad5848598a0f46942a89e9

Code with an issue is located in the BarChart.xaml file and looks like this:

<chart:BarSeries.DataMarker>
              <chart:ChartDataMarker ShowLabel="True">
                <chart:ChartDataMarker.LabelStyle>
                  <chart:DataMarkerLabelStyle LabelPosition="Inner"
                                              LabelFormat="#.#'B'"
                                              Font="12">
                  </chart:DataMarkerLabelStyle>
                </chart:ChartDataMarker.LabelStyle>
                <chart:ChartDataMarker.LabelTemplate>
                  <DataTemplate>
                      <!--<Grid></Grid>-->
                    <Label Text="TEST"/>
                  </DataTemplate>
                </chart:ChartDataMarker.LabelTemplate>
              </chart:ChartDataMarker>
            </chart:BarSeries.DataMarker>

If you comment out the Label element in the DataTemplate and uncomment the empty Grid element the issue is gone.

To reproduce the problem run the Android app and navigate to the Bar series, the exception should be thrown and the app crashes.

SfChart_DataTemplate_Exception.zip

[KarthikRajaAKR]

Hi @samhouts,

We are facing a similar issue with SfSchedule also. While placing Button directly in DataTemplate exception throws, but working fine while placing Button inside Grid.

<schedule:SfSchedule.AppointmentTemplate> <DataTemplate> <Button x:Name="Meeting" Text="{Binding Subject}"/> </DataTemplate> </schedule:SfSchedule.AppointmentTemplate>

We hope this will be fixed in the upcoming release.

Regards,
Karthik Raja

[hjharvey-MSFT]

I was able to replicate this issue using only Xamarin Forms controls and custom a custom renderer
Attached is the Repo. The root cause revolves around the Custom Renderer and this piece of code

        public override void AddView(global::Android.Views.View child)
        {
            if (child is Android.Widget.Button head && (head.Text == "Show" || head.Text == "Hide"))
            {
                base.AddView(child);
            }
        }

this is a bit funky, and honestly I don't remember why I was doing this, but this same code is ok in an iOS project but causes issues in Android.

AndroidWidthNullPointer.zip

[mkieres]

This issue is a blocker for our customer to get onto the latest version of Xamarin.Forms. I was wondering if the Xamarin.Forms team could provide an estimate on when this might get fixed?

[solomonfried]

This will get around this problem until it is fixed without having to change your templates.

In MainActivity.cs add the following line in OnCreate right before Forms.Init(this, bundle)

Forms.SetFlags("UseLegacyRenderers");

[solomonfried]

Same issue will occur when adding a View to the CenterView of a DoughnutSeries
If I add a directly to the Chart, it will crash on Android.
If I do this instead
<chart:DoughnutSeries.CenterView> <ContentView> <Label/> </ContentView> </chart:DoughnutSeries.CenterView>
It will work.

I am still falling back toForms.SetFlags("UseLegacyRenderers");(see previous post) until this issue is resolved.

[HemalathaMarikuma-syncfusion]

Can you please provide a timeline to fix this issue which will be helpful to track this status?

[DevakumarD]

Hi Xamarin.Forms team, Please update the proper timeline for fixing this issue. Since we have a higher priority on this issue, it needs to be addressed.

[nschoenberg]

@samhouts Also crashing in our App with Control SfCircularProgressBar. Syncfusion directed me to this issue. Can confirm it is working in 4.3. Please let me know If you need more information. I need a workarround or fix for xamarin 4.4. Thanks

[InquisitorJax]

@nschoenberg Did hosting the content of SfCircularProgressBar in a Grid not work for you? (the work-around is posted in the header of this issue)
This worked for me:

[nschoenberg]

@InquisitorJax Thanks a lot i misunderstood that this is a work around that might work as well for other controls. Will try Forms.SetFlags("UseLegacyRenderers"); as well. I let you guys know what works best for me. Thanks again

[nschoenberg]

@InquisitorJax Can confirm this is working for us. Instead of a grid we use a ContentView to host the syncfusion control. We believe that this is cheaper compared to a grid. At least this is working for SfCircularProgressBar.

@samhouts I recommend to get in touch about this issue and work it out with syncfusion. Afaik fast renderer was introduced to flatten the view hierarchy. Embedding controls in host controls seems wrong to me.

[PureWeen]

Once the nuget for this build is ready
https://dev.azure.com/xamarin/public/_build/results?buildId=14319&view=results

Can everyone test the nuget?

[nschoenberg]

@PureWeen So the issue is probably fixed in that pre-build? I would like to use a new service release of xamarin 4.4 with that fix. When a test is required before that goes into new service release i will invest some time

[eli191]

I have these and I get that exception (crash).
<PackageReference Include="Xamarin.Forms" Version="4.5.0.282-pre4" /> <PackageReference Include="Syncfusion.Xamarin.SfGauge" Version="17.4.0.50" /> <PackageReference Include="Syncfusion.Xamarin.SfProgressBar" Version="17.4.0.50" />

Forms.SetFlags("UseLegacyRenderers"); did not change anything.

[PureWeen]

4.4 based fixed

https://dev.azure.com/xamarin/public/_build/results?buildId=14319&view=artifacts&type=publishedArtifacts

[eli191]

@PureWeen What do you mean? I had the XF 4.4.0.991640, and it was not working either. Where is the release where it is working please?
EDIT: It is working for me now after putting the Label in <GaugeAnnotation.View> inside Grid as suggested before.

[PureWeen]

It's at the link I posted. They are just nugets you can download and then install locally. There are just a lot of scenarios here in this thread so I figured if people could test their respective ones then that would help out to fully verify the fix

[nschoenberg]

@PureWeen Thanks alot for your hard work. I updated my support ticket on the side of syncfusion and pointed them into your direction, kindly requesting help of there QA team. Hope that helps

[Devaraj-Sekar]

Hi @PureWeen / @nschoenberg ,

Thank you for the update. The provided patch fixed the crash in SfCircularProgressBar, Could please update the appropriate time line for the release version of the provided fix?

Regards,
Devaraj S

[DevakumarD]

Hi @PureWeen,

Thanks, the provided nuget fix resolved the issue in SfChart too. Could you please update the appropriate timeline for the official release version of the provided fix?

Regards,
Devakumar D

[mark-emc]

I just ran into this issue using XF 4.4.0.991640 with VS 2019 and running on a Samsung s9.

I started a new Xamarin forms project using the Shell template. Then I added a new tabbed page with this XAML:
https://docs.microsoft.com/en-us/xamarin/xamarin-forms/xaml/xaml-basics/get-started-with-xaml?tabs=windows#code-try-3

Switching back and forth between the new page and another throws the error.

Wrapping the Label in a ContentView tag fixes the problem.

[chrisparkeronline]

I ran across this issue recently with 4.5.0.356 using SFListView. My issue was a Label within the header template. I surround it with a StackLayout and everything worked fine.

[solomonfried]

You can use something more light-weight like a ContentView. Works just as well.

[ScottBTR]

Hi @PureWeen,

As described previously by @mkieres above we are still expiercing the same issue post-update:

Java.Lang.NullPointerException: 'Attempt to read from field 'int android.view.ViewGroup$LayoutParams.width' on a null object reference'

I'm wondering if it would be possible to look into this case? I've provided some info about the occurence below but am happy to provide more if required.

Currently using:
Xamarin.Forms version: v4.5.0.396
Syncfusion version: v17.4.0.44

The issue occurs when using the following Data Template:
(Note: our current work around is wrapping the within a which does stop this issue occuring)

<DataTemplate x:Key="TemplateToUse">
    <Label Text="Sf Issue" />
</DataTemplate>

<sfchart:ColumnSeries.DataMarker>
<sfchart:ChartDataMarker ShowLabel="True"
                         LabelTemplate="{StaticResource TemplateToUse}">
  <sfchart:ChartDataMarker.LabelStyle>
    <sfchart:DataMarkerLabelStyle BorderThickness="0"
                                  BackgroundColor="Transparent" />
  </sfchart:ChartDataMarker.LabelStyle>
</sfchart:ChartDataMarker>
</sfchart:ColumnSeries.DataMarker>

I recieve the following call stack:

    [External Code] 
>   0x1 in System.Diagnostics.Debugger.Mono_UnhandledException at /Users/builder/jenkins/workspace/archive-mono/2019-10/android/release/mcs/class/corlib/System.Diagnostics/Debugger.cs:120,4   C#
    0x12 in System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw at /Users/builder/jenkins/workspace/archive-mono/2019-10/android/release/mcs/class/referencesource/mscorlib/system/runtime/exceptionservices/exceptionservicescommon.cs:157,13 C#
    0x161 in Xamarin.Forms.Platform.Android.FastRenderers.LabelRenderer.Xamarin.Forms.Platform.Android.IVisualElementRenderer.GetDesiredSize at D:\a\1\s\Xamarin.Forms.Platform.Android\FastRenderers\LabelRenderer.cs:131,4    C#
    0xB3 in Xamarin.Forms.Platform.Android.Platform.GetNativeSize at D:\a\1\s\Xamarin.Forms.Platform.Android\Platform.cs:1349,4 C#
    0x3 in Xamarin.Forms.Forms.AndroidPlatformServices.GetNativeSize at D:\a\1\s\Xamarin.Forms.Platform.Android\Forms.cs:855,5  C#
    0x2D in Xamarin.Forms.VisualElement.OnSizeRequest at D:\a\1\s\Xamarin.Forms.Core\VisualElement.cs:787,4 C#
    0x3 in Xamarin.Forms.VisualElement.OnMeasure at D:\a\1\s\Xamarin.Forms.Core\VisualElement.cs:770,4  C#
    0x56 in Xamarin.Forms.VisualElement.GetSizeRequest at D:\a\1\s\Xamarin.Forms.Core\VisualElement.cs:646,4    C#
    0x57 in Xamarin.Forms.VisualElement.Measure at D:\a\1\s\Xamarin.Forms.Core\VisualElement.cs:704,4   C#
    0x54 in Xamarin.Forms.Platform.Android.ViewRenderer<Syncfusion.SfChart.XForms.SfChart,Com.Syncfusion.Charts.SfChart>.OnLayout at D:\a\1\s\Xamarin.Forms.Platform.Android\ViewRenderer.cs:207,4  C#
    0x10 in Xamarin.Forms.Platform.Android.FormsViewGroup.n_OnLayout_ZIIII at D:\a\1\s\Xamarin.Forms.Platform.Android.FormsViewGroup\obj\Release\generated\src\Xamarin.Forms.Platform.Android.FormsViewGroup.cs:198,4   C#
    0x97 in Xamarin.Forms.Platform.Android.FormsViewGroup.MeasureAndLayout at D:\a\1\s\Xamarin.Forms.Platform.Android.FormsViewGroup\obj\Release\generated\src\Xamarin.Forms.Platform.Android.FormsViewGroup.cs:181,5   C#
    0x171 in Xamarin.Forms.Platform.Android.VisualElementTracker.UpdateLayout at D:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementTracker.cs:97,5   C#
    0x1E in Xamarin.Forms.Platform.Android.VisualElementRenderer<Syncfusion.SfChart.XForms.SfChart>.UpdateLayout at D:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementRenderer.cs:141,4  C#
    0x3A in Xamarin.Forms.Platform.Android.VisualElementRenderer<Xamarin.Forms.View>.UpdateLayout at D:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementRenderer.cs:397,5 C#
    0x1E in Xamarin.Forms.Platform.Android.VisualElementRenderer<Xamarin.Forms.View>.OnLayout at D:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementRenderer.cs:382,4 C#
    0x10 in Xamarin.Forms.Platform.Android.FormsViewGroup.n_OnLayout_ZIIII at D:\a\1\s\Xamarin.Forms.Platform.Android.FormsViewGroup\obj\Release\generated\src\Xamarin.Forms.Platform.Android.FormsViewGroup.cs:198,4   C#
    0x97 in Xamarin.Forms.Platform.Android.FormsViewGroup.MeasureAndLayout at D:\a\1\s\Xamarin.Forms.Platform.Android.FormsViewGroup\obj\Release\generated\src\Xamarin.Forms.Platform.Android.FormsViewGroup.cs:181,5   C#
    0x171 in Xamarin.Forms.Platform.Android.VisualElementTracker.UpdateLayout at D:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementTracker.cs:97,5   C#
    0x1E in Xamarin.Forms.Platform.Android.VisualElementRenderer<Xamarin.Forms.View>.UpdateLayout at D:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementRenderer.cs:141,4 C#
    0x3A in Xamarin.Forms.Platform.Android.VisualElementRenderer<Xamarin.Forms.View>.UpdateLayout at D:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementRenderer.cs:397,5 C#
    0x1E in Xamarin.Forms.Platform.Android.VisualElementRenderer<Xamarin.Forms.View>.OnLayout at D:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementRenderer.cs:382,4 C#
    0x10 in Xamarin.Forms.Platform.Android.FormsViewGroup.n_OnLayout_ZIIII at D:\a\1\s\Xamarin.Forms.Platform.Android.FormsViewGroup\obj\Release\generated\src\Xamarin.Forms.Platform.Android.FormsViewGroup.cs:198,4   C#
    0x97 in Xamarin.Forms.Platform.Android.FormsViewGroup.MeasureAndLayout at D:\a\1\s\Xamarin.Forms.Platform.Android.FormsViewGroup\obj\Release\generated\src\Xamarin.Forms.Platform.Android.FormsViewGroup.cs:181,5   C#
    0x171 in Xamarin.Forms.Platform.Android.VisualElementTracker.UpdateLayout at D:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementTracker.cs:97,5   C#
    0x1E in Xamarin.Forms.Platform.Android.VisualElementRenderer<Xamarin.Forms.View>.UpdateLayout at D:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementRenderer.cs:141,4 C#
    0x3A in Xamarin.Forms.Platform.Android.VisualElementRenderer<Xamarin.Forms.View>.UpdateLayout at D:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementRenderer.cs:397,5 C#
    0x1E in Xamarin.Forms.Platform.Android.VisualElementRenderer<Xamarin.Forms.View>.OnLayout at D:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementRenderer.cs:382,4 C#
    0x10 in Xamarin.Forms.Platform.Android.FormsViewGroup.n_OnLayout_ZIIII at D:\a\1\s\Xamarin.Forms.Platform.Android.FormsViewGroup\obj\Release\generated\src\Xamarin.Forms.Platform.Android.FormsViewGroup.cs:198,4   C#
    0x97 in Xamarin.Forms.Platform.Android.FormsViewGroup.MeasureAndLayout at D:\a\1\s\Xamarin.Forms.Platform.Android.FormsViewGroup\obj\Release\generated\src\Xamarin.Forms.Platform.Android.FormsViewGroup.cs:181,5   C#
    0x171 in Xamarin.Forms.Platform.Android.VisualElementTracker.UpdateLayout at D:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementTracker.cs:97,5   C#
    0x1E in Xamarin.Forms.Platform.Android.VisualElementRenderer<Xamarin.Forms.View>.UpdateLayout at D:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementRenderer.cs:141,4 C#
    0x14 in Xamarin.Forms.Platform.Android.ScrollViewContainer.OnLayout at D:\a\1\s\Xamarin.Forms.Platform.Android\Renderers\ScrollViewContainer.cs:70,4    C#
    0x40 in Xamarin.Forms.Platform.Android.ScrollViewRenderer.OnLayout at D:\a\1\s\Xamarin.Forms.Platform.Android\Renderers\ScrollViewRenderer.cs:273,4 C#
    0x118 in Xamarin.Forms.Platform.Android.VisualElementTracker.UpdateLayout at D:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementTracker.cs:91,5   C#
    0xB in Xamarin.Forms.Platform.Android.ScrollViewRenderer.UpdateLayout at D:\a\1\s\Xamarin.Forms.Platform.Android\Renderers\ScrollViewRenderer.cs:143,4  C#
    0x1 in Xamarin.Forms.Platform.Android.ScrollViewRenderer.HandleLayoutChanged at D:\a\1\s\Xamarin.Forms.Platform.Android\Renderers\ScrollViewRenderer.cs:120,4   C#
    0x1A5 in Xamarin.Forms.Layout.UpdateChildrenLayout at D:\a\1\s\Xamarin.Forms.Core\Layout.cs:274,6   C#
    0x10 in Xamarin.Forms.Layout.OnSizeAllocated at D:\a\1\s\Xamarin.Forms.Core\Layout.cs:224,4 C#
    0x3 in Xamarin.Forms.VisualElement.SizeAllocated at D:\a\1\s\Xamarin.Forms.Core\VisualElement.cs:792,4  C#
    0x60 in Xamarin.Forms.Layout.ResolveLayoutChanges at D:\a\1\s\Xamarin.Forms.Core\Layout.cs:392,6    C#

Here's the Stack Trace:

Java.Lang.NullPointerException: Attempt to read from field 'int android.view.ViewGroup$LayoutParams.width' on a null object reference    
  at Java.Interop.JniEnvironment+InstanceMethods.CallNonvirtualVoidMethod (Java.Interop.JniObjectReference instance, Java.Interop.JniObjectReference type, Java.Interop.JniMethodInfo method, Java.Interop.JniArgumentValue* args) [0x0008e] in <26521a5118b44c858c385715922b9d5d>:0 
  at Java.Interop.JniPeerMembers+JniInstanceMethods.InvokeNonvirtualVoidMethod (System.String encodedMember, Java.Interop.IJavaPeerable self, Java.Interop.JniArgumentValue* parameters) [0x0001f] in <26521a5118b44c858c385715922b9d5d>:0 
  at Android.Widget.TextView.set_HintFormatted (Java.Lang.ICharSequence value) [0x00029] in <4ccdb3137d974856b786e1aeebbfbab6>:0 
  at Android.Widget.TextView.set_Hint (System.String value) [0x0000d] in <4ccdb3137d974856b786e1aeebbfbab6>:0 
  at Xamarin.Forms.Platform.Android.FastRenderers.LabelRenderer.Xamarin.Forms.Platform.Android.IVisualElementRenderer.GetDesiredSize (System.Int32 widthConstraint, System.Int32 heightConstraint) [0x0015a] in D:\a\1\s\Xamarin.Forms.Platform.Android\FastRenderers\LabelRenderer.cs:131 
  at Xamarin.Forms.Platform.Android.Platform.GetNativeSize (Xamarin.Forms.VisualElement view, System.Double widthConstraint, System.Double heightConstraint) [0x000ae] in D:\a\1\s\Xamarin.Forms.Platform.Android\Platform.cs:1349 
  at Xamarin.Forms.Forms+AndroidPlatformServices.GetNativeSize (Xamarin.Forms.VisualElement view, System.Double widthConstraint, System.Double heightConstraint) [0x00000] in D:\a\1\s\Xamarin.Forms.Platform.Android\Forms.cs:855 
  at Xamarin.Forms.VisualElement.OnSizeRequest (System.Double widthConstraint, System.Double heightConstraint) [0x00025] in D:\a\1\s\Xamarin.Forms.Core\VisualElement.cs:787 
  at Xamarin.Forms.VisualElement.OnMeasure (System.Double widthConstraint, System.Double heightConstraint) [0x00000] in D:\a\1\s\Xamarin.Forms.Core\VisualElement.cs:770 
  at Xamarin.Forms.VisualElement.GetSizeRequest (System.Double widthConstraint, System.Double heightConstraint) [0x00053] in D:\a\1\s\Xamarin.Forms.Core\VisualElement.cs:646 
  at Xamarin.Forms.VisualElement.Measure (System.Double widthConstraint, System.Double heightConstraint, Xamarin.Forms.MeasureFlags flags) [0x00054] in D:\a\1\s\Xamarin.Forms.Core\VisualElement.cs:704 
  at Syncfusion.SfChart.XForms.Droid.SfChartRenderer.GetNativeView (System.Object bindingContext, Syncfusion.SfChart.XForms.SfChart formChart, Xamarin.Forms.View view, Android.Views.ViewGroup+LayoutParams layoutParams) [0x0001d] in <4a2670bfcbc849bea198cd3e499de357>:0 
  at Syncfusion.SfChart.XForms.Droid.SfChartRenderer.GetNativeView (System.Object bindingContext, Syncfusion.SfChart.XForms.SfChart formChart, Xamarin.Forms.DataTemplate dataTemplate, Android.Views.ViewGroup+LayoutParams layoutParams) [0x0003f] in <4a2670bfcbc849bea198cd3e499de357>:0 
  at Syncfusion.SfChart.XForms.Droid.ChartDataMarkerMapping.NativeSeries_DataMarkerLabelCreated (System.Object sender, Com.Syncfusion.Charts.ChartSeries+DataMarkerLabelCreatedEventArgs e) [0x00125] in <4a2670bfcbc849bea198cd3e499de357>:0 
  at Com.Syncfusion.Charts.ChartSeries.OnDataMarkerLabelCreated (Com.Syncfusion.Charts.DataMarkerLabel dataMarkerLabel) [0x0007f] in <4a2670bfcbc849bea198cd3e499de357>:0 
  at Com.Syncfusion.Charts.XyDataSeries.CreateDataMarkerLabels () [0x0035f] in <4a2670bfcbc849bea198cd3e499de357>:0 
  at Com.Syncfusion.Charts.ChartBase.UpdateArea () [0x00157] in <4a2670bfcbc849bea198cd3e499de357>:0 
  at Com.Syncfusion.Charts.ChartBase.OnMeasureChart () [0x00031] in <4a2670bfcbc849bea198cd3e499de357>:0 
  at Com.Syncfusion.Charts.SfChart.OnMeasure (System.Int32 widthMeasureSpec, System.Int32 heightMeasureSpec) [0x001f4] in <4a2670bfcbc849bea198cd3e499de357>:0 
  at Android.Views.View.n_OnMeasure_II (System.IntPtr jnienv, System.IntPtr native__this, System.Int32 widthMeasureSpec, System.Int32 heightMeasureSpec) [0x00009] in <4ccdb3137d974856b786e1aeebbfbab6>:0 
  at (wrapper dynamic-method) Android.Runtime.DynamicMethodNameCounter.37(intptr,intptr,int,int)
  --- End of managed Java.Lang.NullPointerException stack trace ---
java.lang.NullPointerException: Attempt to read from field 'int android.view.ViewGroup$LayoutParams.width' on a null object reference
    at android.widget.TextView.checkForRelayout(TextView.java:10728)
    at android.widget.TextView.setHintInternal(TextView.java:7008)
    at android.widget.TextView.setHint(TextView.java:6997)
    at crc64204ae6d284429e79.SfChart.n_onMeasure(Native Method)
    at crc64204ae6d284429e79.SfChart.onMeasure(SfChart.java:53)
    at android.view.View.measure(View.java:26367)
    at crc643f46942d9dd1fff9.ViewRenderer_2.n_onLayout(Native Method)
    at crc643f46942d9dd1fff9.ViewRenderer_2.onLayout(ViewRenderer_2.java:47)
    at android.view.View.layout(View.java:23706)
    at android.view.ViewGroup.layout(ViewGroup.java:6663)
    at com.xamarin.forms.platform.android.FormsViewGroup.measureAndLayout(FormsViewGroup.java:37)
    at crc643f46942d9dd1fff9.VisualElementRenderer_1.n_onLayout(Native Method)
    at crc643f46942d9dd1fff9.VisualElementRenderer_1.onLayout(VisualElementRenderer_1.java:81)
    at android.view.View.layout(View.java:23706)
    at android.view.ViewGroup.layout(ViewGroup.java:6663)
    at com.xamarin.forms.platform.android.FormsViewGroup.measureAndLayout(FormsViewGroup.java:37)
    at crc643f46942d9dd1fff9.VisualElementRenderer_1.n_onLayout(Native Method)
    at crc643f46942d9dd1fff9.VisualElementRenderer_1.onLayout(VisualElementRenderer_1.java:81)
    at android.view.View.layout(View.java:23706)
    at android.view.ViewGroup.layout(ViewGroup.java:6663)
    at com.xamarin.forms.platform.android.FormsViewGroup.measureAndLayout(FormsViewGroup.java:37)
    at crc643f46942d9dd1fff9.VisualElementRenderer_1.n_onLayout(Native Method)
    at crc643f46942d9dd1fff9.VisualElementRenderer_1.onLayout(VisualElementRenderer_1.java:81)
    at android.view.View.layout(View.java:23706)
    at android.view.ViewGroup.layout(ViewGroup.java:6663)
    at com.xamarin.forms.platform.android.FormsViewGroup.measureAndLayout(FormsViewGroup.java:37)
    at crc643f46942d9dd1fff9.ScrollViewContainer.n_onLayout(Native Method)
    at crc643f46942d9dd1fff9.ScrollViewContainer.onLayout(ScrollViewContainer.java:54)
    at android.view.View.layout(View.java:23706)
    at android.view.ViewGroup.layout(ViewGroup.java:6663)
    at android.widget.FrameLayout.layoutChildren(FrameLayout.java:332)
    at android.widget.FrameLayout.onLayout(FrameLayout.java:270)
    at android.support.v4.widget.NestedScrollView.onLayout(NestedScrollView.java:1733)
    at crc643f46942d9dd1fff9.ScrollViewRenderer.n_onLayout(Native Method)
    at crc643f46942d9dd1fff9.ScrollViewRenderer.onLayout(ScrollViewRenderer.java:91)
    at android.view.View.layout(View.java:23706)
    at android.view.ViewGroup.layout(ViewGroup.java:6663)
    at crc643f46942d9dd1fff9.VisualElementRenderer_1.n_onLayout(Native Method)
    at crc643f46942d9dd1fff9.VisualElementRenderer_1.onLayout(VisualElementRenderer_1.java:81)
    at android.view.View.layout(View.java:23706)
    at android.view.ViewGroup.layout(ViewGroup.java:6663)
    at com.xamarin.forms.platform.android.FormsViewGroup.measureAndLayout(FormsViewGroup.java:37)
    at crc643f46942d9dd1fff9.VisualElementRenderer_1.n_onLayout(Native Method)
    at crc643f46942d9dd1fff9.VisualElementRenderer_1.onLayout(VisualElementRenderer_1.java:81)
    at android.view.View.layout(View.java:23706)
    at android.view.ViewGroup.layout(ViewGroup.java:6663)
    at com.xamarin.forms.platform.android.FormsViewGroup.measureAndLayout(FormsViewGroup.java:37)
    at crc643f46942d9dd1fff9.VisualElementRenderer_1.n_onLayout(Native Method)
    at crc643f46942d9dd1fff9.VisualElementRenderer_1.onLayout(VisualElementRenderer_1.java:81)
    at android.view.View.layout(View.java:23706)
    at android.view.ViewGroup.layout(ViewGroup.java:6663)
    at com.xamarin.forms.platform.android.FormsViewGroup.measureAndLayout(FormsViewGroup.java:37)
    at crc643f46942d9dd1fff9.PageRenderer.n_onLayout(Native Method)
    at crc643f46942d9dd1fff9.PageRenderer.onLayout(PageRenderer.java:72)
    at android.view.View.layout(View.java:23706)
    at android.view.ViewGroup.layout(ViewGroup.java:6663)
    at com.xamarin.forms.platform.android.FormsViewGroup.measureAndLayout(FormsViewGroup.java:37)
    at crc64720bb2db43a66fe9.NavigationPageRenderer.n_onLayout(Native Method)
    at crc64720bb2db43a66fe9.NavigationPageRenderer.onLayout(NavigationPageRenderer.java:65)
    at android.view.View.layout(View.java:23706)
    at android.view.ViewGroup.layout(ViewGroup.java:6663)
    at com.xamarin.forms.platform.android.FormsViewGroup.measureAndLayout(FormsViewGroup.java:37)
    at crc643f46942d9dd1fff9.PageContainer.n_onLayout(Native Method)
    at crc643f46942d9dd1fff9.PageContainer.onLayout(PageContainer.java:54)
    at android.view.View.layout(View.java:23706)
    at android.view.ViewGroup.layout(ViewGroup.java:6663)
    at android.support.v4.view.ViewPager.onLayout(ViewPager.java:1775)
    at android.view.View.layout(View.java:23706)
    at android.view.ViewGroup.layout(ViewGroup.java:6663)
    at crc64720bb2db43a66fe9.TabbedPageRenderer.n_onLayout(Native Method)
    at crc64720bb2db43a66fe9.TabbedPageRenderer.onLayout(TabbedPageRenderer.java:73)
    at android.view.View.layout(View.java:23706)
    at android.view.ViewGroup.layout(ViewGroup.java:6663)
    at com.xamarin.forms.platform.android.FormsViewGroup.measureAndLayout(FormsViewGroup.java:37)
    at crc64720bb2db43a66fe9.NavigationPageRenderer.n_onLayout(Native Method)
    at crc64720bb2db43a66fe9.NavigationPageRenderer.onLayout(NavigationPageRenderer.java:65)
    at android.view.View.layout(View.java:23706)
    at android.view.ViewGroup.layout(ViewGroup.java:6663)
    at com.xamarin.forms.platform.android.FormsViewGroup.measureAndLayout(FormsViewGroup.java:37)
    at crc643f46942d9dd1fff9.PlatformRenderer.n_onLayout(Native Method)
    at crc643f46942d9dd1fff9.PlatformRenderer.onLayout(PlatformRenderer.java:63)
    at android.view.View.layout(View.java:23706)
    at android.view.ViewGroup.layout(ViewGroup.java:6663)
    at android.widget.RelativeLayout.onLayout(RelativeLayout.java:1103)
    at android.view.View.layout(View.java:23706)
    at android.view.ViewGroup.layout(ViewGroup.java:6663)
    at android.widget.FrameLayout.layoutChildren(FrameLayout.java:332)
    at android.widget.FrameLayout.onLayout(FrameLayout.java:270)
    at android.view.View.layout(View.java:23706)
    at android.view.ViewGroup.layout(ViewGroup.java:6663)
    at android.widget.FrameLayout.layoutChildren(FrameLayout.java:332)
    at android.widget.FrameLayout.onLayout(FrameLayout.java:270)
    at android.view.View.layout(View.java:23706)
    at android.view.ViewGroup.layout(ViewGroup.java:6663)
    at android.widget.FrameLayout.layoutChildren(FrameLayout.java:332)
    at android.widget.FrameLayout.onLayout(FrameLayout.java:270)
    at android.view.View.layout(View.java:23706)
    at android.view.ViewGroup.layout(ViewGroup.java:6663)
    at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1829)
    at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1673)
    at android.widget.LinearLayout.onLayout(LinearLayout.java:1582)
    at android.view.View.layout(View.java:23706)
    at android.view.ViewGroup.layout(ViewGroup.java:6663)
    at android.widget.FrameLayout.layoutChildren(FrameLayout.java:332)
    at android.widget.FrameLayout.onLayout(FrameLayout.java:270)
    at com.android.internal.policy.DecorView.onLayout(DecorView.java:1052)
    at android.view.View.layout(View.java:23706)
    at android.view.ViewGroup.layout(ViewGroup.java:6663)
    at android.view.ViewRootImpl.performLayout(ViewRootImpl.java:3625)
    at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:3085)
    at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:2148)
    at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:8831)
    at android.view.Choreographer$CallbackRecord.run(Choreographer.java:996)
    at android.view.Choreographer.doCallbacks(Choreographer.java:794)
    at android.view.Choreographer.doFrame(Choreographer.java:729)
    at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:981)
    at android.os.Handler.handleCallback(Handler.java:883)
    at android.os.Handler.dispatchMessage(Handler.java:100)
    at android.os.Looper.loop(Looper.java:237)
    at android.app.ActivityThread.main(ActivityThread.java:7777)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1047)

Cheers,
Scott