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SfBarcode - System.NullReferenceException when PopAsync

Hi, i have Page1 with button to Navigation to second page is Page2 and  Page2 only have SfBarcode to show QR code. 

Page2 is work fine but when calling PopAsync to go back Page1 then System.NullReferenceException will appearing with this error 
  

i'm already upgrade Nuget to the last version and the problem is still there.


7 Replies
HJ Huang Jia Wu March 10, 2020 03:10 PM UTC

hello, me too, but only in Xamarin.Android

xamarin.forms ver is 4.5

  at Syncfusion.SfBarcode.XForms.Android.SfBarcodeMapping.OnSfBarcodePropertyChanged (System.String propertyName, Syncfusion.SfBarcode.XForms.SfBarcode barcode, Com.Syncfusion.Barcode.SfBarcode nativeBarcode) [0x004cb] in :0 
  at Syncfusion.SfBarcode.XForms.Android.SfBarcodeRenderer.OnElementPropertyChanged (System.Object sender, System.ComponentModel.PropertyChangedEventArgs e) [0x00014] in :0 
  at (wrapper delegate-invoke) .invoke_void_object_PropertyChangedEventArgs(object,System.ComponentModel.PropertyChangedEventArgs)
  at Xamarin.Forms.BindableObject.OnPropertyChanged (System.String propertyName) [0x00000] in d:\a\1\s\Xamarin.Forms.Core\BindableObject.cs:229 
  at Xamarin.Forms.Element.OnPropertyChanged (System.String propertyName) [0x00000] in d:\a\1\s\Xamarin.Forms.Core\Element.cs:353 
  at Xamarin.Forms.BindableObject.SetValueActual (Xamarin.Forms.BindableProperty property, Xamarin.Forms.BindableObject+BindablePropertyContext context, System.Object value, System.Boolean currentlyApplying, Xamarin.Forms.Internals.SetValueFlags attributes, System.Boolean silent) [0x00114] in d:\a\1\s\Xamarin.Forms.Core\BindableObject.cs:461 
  at Xamarin.Forms.BindableObject.SetValueCore (Xamarin.Forms.BindableProperty property, System.Object value, Xamarin.Forms.Internals.SetValueFlags attributes, Xamarin.Forms.BindableObject+SetValuePrivateFlags privateAttributes) [0x00173] in d:\a\1\s\Xamarin.Forms.Core\BindableObject.cs:397 
  at Xamarin.Forms.BindableObject.SetValue (Xamarin.Forms.BindableProperty property, System.Object value, System.Boolean fromStyle, System.Boolean checkAccess) [0x00042] in d:\a\1\s\Xamarin.Forms.Core\BindableObject.cs:334 
  at Xamarin.Forms.BindableObject.SetValue (Xamarin.Forms.BindableProperty property, System.Object value) [0x00000] in d:\a\1\s\Xamarin.Forms.Core\BindableObject.cs:311 
  at Syncfusion.SfBarcode.XForms.SfBarcode.set_SymbologySettings (Syncfusion.SfBarcode.XForms.BarcodeSettings value) [0x00000] in <7af80dbcf68e44508d679bf82b41c8eb>:0 
  at Syncfusion.SfBarcode.XForms.SfBarcode.Dispose () [0x00008] in <7af80dbcf68e44508d679bf82b41c8eb>:0 
  at Syncfusion.SfBarcode.XForms.Android.SfBarcodeRenderer.Dispose () [0x00008] in :0 
  at Xamarin.Forms.Platform.Android.VisualElementPackager.RemoveChild (Xamarin.Forms.VisualElement view) [0x0007f] in d:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementPackager.cs:272 
  at Xamarin.Forms.Platform.Android.VisualElementPackager.SetElement (Xamarin.Forms.VisualElement oldElement, Xamarin.Forms.VisualElement newElement) [0x000ab] in d:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementPackager.cs:318 
  at Xamarin.Forms.Platform.Android.VisualElementPackager.Dispose (System.Boolean disposing) [0x000a7] in d:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementPackager.cs:86 
  at Xamarin.Forms.Platform.Android.VisualElementPackager.Dispose () [0x00000] in d:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementPackager.cs:61 
  at Xamarin.Forms.Platform.Android.VisualElementRenderer`1[TElement].Dispose (System.Boolean disposing) [0x00081] in d:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementRenderer.cs:301 
  at Xamarin.Forms.Platform.Android.Platform+DefaultRenderer.Dispose (System.Boolean disposing) [0x0001a] in d:\a\1\s\Xamarin.Forms.Platform.Android\Platform.cs:1305 
  at Java.Lang.Object.Dispose () [0x00000] in :0 
  at Xamarin.Forms.Platform.Android.VisualElementPackager.RemoveChild (Xamarin.Forms.VisualElement view) [0x0007f] in d:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementPackager.cs:272 
  at Xamarin.Forms.Platform.Android.VisualElementPackager.SetElement (Xamarin.Forms.VisualElement oldElement, Xamarin.Forms.VisualElement newElement) [0x000ab] in d:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementPackager.cs:318 
  at Xamarin.Forms.Platform.Android.VisualElementPackager.Dispose (System.Boolean disposing) [0x000a7] in d:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementPackager.cs:86 
  at Xamarin.Forms.Platform.Android.VisualElementPackager.Dispose () [0x00000] in d:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementPackager.cs:61 
  at Xamarin.Forms.Platform.Android.VisualElementRenderer`1[TElement].Dispose (System.Boolean disposing) [0x00081] in d:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementRenderer.cs:301 
  at Xamarin.Forms.Platform.Android.Platform+DefaultRenderer.Dispose (System.Boolean disposing) [0x0001a] in d:\a\1\s\Xamarin.Forms.Platform.Android\Platform.cs:1305 
  at Java.Lang.Object.Dispose () [0x00000] in :0 
  at Xamarin.Forms.Platform.Android.VisualElementPackager.RemoveChild (Xamarin.Forms.VisualElement view) [0x0007f] in d:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementPackager.cs:272 
  at Xamarin.Forms.Platform.Android.VisualElementPackager.SetElement (Xamarin.Forms.VisualElement oldElement, Xamarin.Forms.VisualElement newElement) [0x000ab] in d:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementPackager.cs:318 
  at Xamarin.Forms.Platform.Android.VisualElementPackager.Dispose (System.Boolean disposing) [0x000a7] in d:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementPackager.cs:86 
  at Xamarin.Forms.Platform.Android.VisualElementPackager.Dispose () [0x00000] in d:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementPackager.cs:61 
  at Xamarin.Forms.Platform.Android.VisualElementRenderer`1[TElement].Dispose (System.Boolean disposing) [0x00081] in d:\a\1\s\Xamarin.Forms.Platform.Android\VisualElementRenderer.cs:301 
  at Xamarin.Forms.Platform.Android.PageRenderer.Dispose (System.Boolean disposing) [0x00024] in d:\a\1\s\Xamarin.Forms.Platform.Android\Renderers\PageRenderer.cs:58 
  at Java.Lang.Object.Dispose () [0x00000] in :0 
  at Xamarin.Forms.Platform.Android.AppCompat.FragmentContainer.OnDestroyView () [0x0003c] in d:\a\1\s\Xamarin.Forms.Platform.Android\AppCompat\FragmentContainer.cs:88 
  at AndroidX.Fragment.App.Fragment.n_OnDestroyView (System.IntPtr jnienv, System.IntPtr native__this) [0x00008] in D:\a\1\s\generated\androidx.fragment.fragment\obj\Release\monoandroid90\generated\src\AndroidX.Fragment.App.Fragment.cs:1990 
  at (wrapper dynamic-method) Android.Runtime.DynamicMethodNameCounter.66(intptr,intptr)

KI Kien.Phat March 10, 2020 03:25 PM UTC

I think this issue only occurs in the latest version of SfBarcode because before I updated it was fine

HJ Huang Jia Wu March 11, 2020 09:14 AM UTC

Hello, after a lot of test, I found the sfbarcode can't working with xamarin.forms 4.5, after I downgrade to 4.4, everything is working fine

SL Sowmiya Loganathan Syncfusion Team March 11, 2020 12:40 PM UTC

Hi Huang /Kien,   
  
Thank you for contacting Syncfusion support.   
  
We have tried to reproduce the reported issue using SfBarcode with navigating the page using Xamarin Forms (version 4.5) and latest product version (17.4.0.55). But we regret to let you know that we were unable to reproduce it. Please find the sample which we have tried from below,   
  
Kindly try the above sample in your end and let us know the result. Also please revert us with modified sample to replicate the issue, it will helpful for us to provide the precise solution on this.   
  
Regards,  
Sowmiya Loganathan 


HJ Huang Jia Wu March 12, 2020 01:07 AM UTC

Hello dear, thanks for your response, will try your sample later and let you know

AL Alexis August 27, 2020 09:57 PM UTC

Hi,

I have exactly the same issue

I use 4.8.0.1269 Xamarin and I use sfbarcode version 18.2.0.55

Please fix. It's urgent.

My logs:

 UNHANDLED EXCEPTION:
08-27 23:51:22.781 I/MonoDroid(31537): System.NullReferenceException: Object reference not set to an instance of an object.
08-27 23:51:22.782 I/MonoDroid(31537):   at Syncfusion.SfBarcode.XForms.Android.SfBarcodeRenderer.OnElementPropertyChanged (System.Object sender, System.ComponentModel.PropertyChangedEventArgs e) [0x00014] in <573b72f24086444780aac949531c85ba>:0 
08-27 23:51:22.782 I/MonoDroid(31537):   at (wrapper delegate-invoke) .invoke_void_object_PropertyChangedEventArgs(object,System.ComponentModel.PropertyChangedEventArgs)
08-27 23:51:22.782 I/MonoDroid(31537):   at Xamarin.Forms.BindableObject.OnPropertyChanged (System.String propertyName) [0x00000] in D:\a\1\s\Xamarin.Forms.Core\BindableObject.cs:229 
08-27 23:51:22.782 I/MonoDroid(31537):   at Xamarin.Forms.Element.OnPropertyChanged (System.String propertyName) [0x00000] in D:\a\1\s\Xamarin.Forms.Core\Element.cs:353 
08-27 23:51:22.782 I/MonoDroid(31537):   at Xamarin.Forms.BindableObject.SetValueActual (Xamarin.Forms.BindableProperty property, Xamarin.Forms.BindableObject+BindablePropertyContext context, System.Object value, System.Boolean currentlyApplying, Xamarin.Forms.Internals.SetValueFlags attributes, System.Boolean silent) [0x00114] in D:\a\1\s\Xamarin.Forms.Core\BindableObject.cs:461 
08-27 23:51:22.782 I/MonoDroid(31537):   at Xamarin.Forms.BindableObject.SetValueCore (Xamarin.Forms.BindableProperty property, System.Object value, Xamarin.Forms.Internals.SetValueFlags attributes, Xamarin.Forms.BindableObject+SetValuePrivateFlags privateAttributes) [0x00173] in D:\a\1\s\Xamarin.Forms.Core\BindableObject.cs:397 
08-27 23:51:22.782 I/MonoDroid(31537):   at Xamarin.Forms.BindableObject.SetValue (Xamarin.Forms.BindableProperty property, System.Object value, System.Boolean fromStyle, System.Boolean checkAccess) [0x00042] in D:\a\1\s\Xamarin.Forms.Core\BindableObject.cs:334 
08-27 23:51:22.782 I/MonoDroid(31537):   at Xamarin.Forms.BindableObject.SetValue (Xamarin.Forms.BindableProperty property, System.Object value) [0x00000] in D:\a\1\s\Xamarin.Forms.Core\BindableObject.cs:311 
08-27 23:51:22.782 I/MonoDroid(31537):   at Xamarin.Forms.VisualElement.set_Scale (System.Double value) [0x00000] in D:\a\1\s\Xamarin.Forms.Core\VisualElement.cs:443 
08-27 23:51:22.782 I/MonoDroid(31537):   at Rg.Plugins.Popup.Animations.ScaleAnimation.Disposing (Xamarin.Forms.View content, Rg.Plugins.Popup.Pages.PopupPage page) [0x0001b] in C:\Users\mhvdi\Documents\OpenSource\Rg.Plugins.Popup\Rg.Plugins.Popup\Animations\ScaleAnimation.cs:56 
08-27 23:51:22.782 I/MonoDroid(31537):   at Rg.Plugins.Popup.Pages.PopupPage.DisposingAnimation () [0x00008] in C:\Users\mhvdi\Documents\OpenSource\Rg.Plugins.Popup\Rg.Plugins.Popup\Pages\PopupPage.cs:212 
08-27 23:51:22.782 I/MonoDroid(31537):   at Rg.Plugins.Popup.Services.PopupNavigationImpl+<>c__DisplayClass23_0.b__0 () [0x001f2] in C:\Users\mhvdi\Documents\OpenSource\Rg.Plugins.Popup\Rg.Plugins.Popup\Services\PopupNavigationImpl.cs:154 
08-27 23:51:22.782 I/MonoDroid(31537):   at Rg.Plugins.Popup.Services.PopupNavigationImpl+<>c__DisplayClass28_0.b__0 () [0x00025] in C:\Users\mhvdi\Documents\OpenSource\Rg.Plugins.Popup\Rg.Plugins.Popup\Services\PopupNavigationImpl.cs:210 
08-27 23:51:22.782 I/MonoDroid(31537):   at Rg.Plugins.Popup.Popup+<>c__DisplayClass12_0.b__0 () [0x00029] in C:\Users\mhvdi\Documents\OpenSource\Rg.Plugins.Popup\Rg.Plugins.Popup\Platforms\Android\Popup.cs:44 
08-27 23:51:22.782 I/MonoDroid(31537):   at System.Runtime.CompilerServices.AsyncMethodBuilderCore+<>c.b__7_0 (System.Object state) [0x00000] in /Users/builder/jenkins/workspace/archive-mono/2020-02/android/release/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/AsyncMethodBuilder.cs:1021 
08-27 23:51:22.782 I/MonoDroid(31537):   at Android.App.SyncContext+<>c__DisplayClass2_0.b__0 () [0x00000] in :0 
08-27 23:51:22.782 I/MonoDroid(31537):   at Java.Lang.Thread+RunnableImplementor.Run () [0x00008] in :0 
08-27 23:51:22.782 I/MonoDroid(31537):   at Java.Lang.IRunnableInvoker.n_Run (System.IntPtr jnienv, System.IntPtr native__this) [0x00008] in :0 
08-27 23:51:22.782 I/MonoDroid(31537):   at (wrapper dynamic-method) Android.Runtime.DynamicMethodNameCounter.1(intptr,intptr)

SL Sowmiya Loganathan Syncfusion Team August 28, 2020 01:00 PM UTC

Hi Alexis,   
 
We have created a new incident under your Direct trac account . We suggest you to follow up with the incident for further updates. Please log in using the below link.  
   
Regards,   
Sowmiya Loganathan   


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