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Random errors at startup

At startup; I randomly have these messages :

Microsoft.JSInterop.JSException: Cannot set property 'blazor__instance' of null
TypeError: Cannot set property 'blazor__instance' of null
    at new s (http://localhost:7120/_content/Syncfusion.Blazor/scripts/sf-tab-b58c64.min.js:1:636)
    at Object.initialize (http://localhost:7120/_content/Syncfusion.Blazor/scripts/sf-tab-b58c64.min.js:1:20026)
    at http://localhost:7120/_framework/blazor.webassembly.js:1:9808
    at new Promise (<anonymous>)
    at Object.beginInvokeJSFromDotNet (http://localhost:7120/_framework/blazor.webassembly.js:1:9776)
    at _mono_wasm_invoke_js_marshalled (http://localhost:7120/_framework/wasm/dotnet.3.2.0.js:1:171294)
    at do_icall (<anonymous>:wasm-function[6049]:0x10f8b1)
    at do_icall_wrapper (<anonymous>:wasm-function[1896]:0x50b6a)
    at interp_exec_method (<anonymous>:wasm-function[1120]:0x2588e)
    at interp_runtime_invoke (<anonymous>:wasm-function[5655]:0xf7391)
  at System.Threading.Tasks.ValueTask`1[TResult].get_Result () <0x4899880 + 0x00034> in <filename unknown>:0 
  at Microsoft.JSInterop.JSRuntimeExtensions.InvokeVoidAsync (Microsoft.JSInterop.IJSRuntime jsRuntime, System.String identifier, System.Object[] args) <0x4528270 + 0x000e4> in <filename unknown>:0 
  at Syncfusion.Blazor.SfBaseComponent.InvokeMethod (System.String methodName, System.Object[] methodParams) <0x4c49800 + 0x000d6> in <filename unknown>:0 
  at Syncfusion.Blazor.Navigations.SfTab.OnAfterScriptRendered () <0x4d9aae0 + 0x000fa> in <filename unknown>:0 
  at Syncfusion.Blazor.SfBaseComponent.OnAfterRenderAsync (System.Boolean firstRender) <0x4553280 + 0x00348> in <filename unknown>:0 
  at Syncfusion.Blazor.Navigations.SfTab.OnAfterRenderAsync (System.Boolean firstRender) <0x4557b40 + 0x003dc> in <filename unknown>:0 
  at Microsoft.AspNetCore.Components.RenderTree.Renderer.GetErrorHandledTask (System.Threading.Tasks.Task taskToHandle) <0x404fcb0 + 0x000b6> in <filename unknown>:0 
crit: Microsoft.AspNetCore.Components.WebAssembly.Rendering.WebAssemblyRenderer[100]
      Unhandled exception rendering component: Cannot set property 'blazor__instance' of null
      TypeError: Cannot set property 'blazor__instance' of null
          at new o (http://localhost:7120/_content/Syncfusion.Blazor/scripts/sf-toolbar-b58c64.min.js:1:652)
          at Object.initialize (http://localhost:7120/_content/Syncfusion.Blazor/scripts/sf-toolbar-b58c64.min.js:1:31450)
          at http://localhost:7120/_framework/blazor.webassembly.js:1:9808
          at new Promise (<anonymous>)
          at Object.beginInvokeJSFromDotNet (http://localhost:7120/_framework/blazor.webassembly.js:1:9776)
          at _mono_wasm_invoke_js_marshalled (http://localhost:7120/_framework/wasm/dotnet.3.2.0.js:1:171294)
          at do_icall (<anonymous>:wasm-function[6049]:0x10f8b1)
          at do_icall_wrapper (<anonymous>:wasm-function[1896]:0x50b6a)
          at interp_exec_method (<anonymous>:wasm-function[1120]:0x2588e)
          at interp_runtime_invoke (<anonymous>:wasm-function[5655]:0xf7391)
Microsoft.JSInterop.JSException: Cannot set property 'blazor__instance' of null
TypeError: Cannot set property 'blazor__instance' of null
    at new o (http://localhost:7120/_content/Syncfusion.Blazor/scripts/sf-toolbar-b58c64.min.js:1:652)
    at Object.initialize (http://localhost:7120/_content/Syncfusion.Blazor/scripts/sf-toolbar-b58c64.min.js:1:31450)
    at http://localhost:7120/_framework/blazor.webassembly.js:1:9808
    at new Promise (<anonymous>)
    at Object.beginInvokeJSFromDotNet (http://localhost:7120/_framework/blazor.webassembly.js:1:9776)
    at _mono_wasm_invoke_js_marshalled (http://localhost:7120/_framework/wasm/dotnet.3.2.0.js:1:171294)
    at do_icall (<anonymous>:wasm-function[6049]:0x10f8b1)
    at do_icall_wrapper (<anonymous>:wasm-function[1896]:0x50b6a)
    at interp_exec_method (<anonymous>:wasm-function[1120]:0x2588e)
    at interp_runtime_invoke (<anonymous>:wasm-function[5655]:0xf7391)
  at System.Threading.Tasks.ValueTask`1[TResult].get_Result () <0x4899880 + 0x00034> in <filename unknown>:0 
  at Microsoft.JSInterop.JSRuntimeExtensions.InvokeVoidAsync (Microsoft.JSInterop.IJSRuntime jsRuntime, System.String identifier, System.Object[] args) <0x4528270 + 0x000e4> in <filename unknown>:0 
  at Syncfusion.Blazor.SfBaseComponent.InvokeMethod (System.String methodName, System.Object[] methodParams) <0x4c49800 + 0x000d6> in <filename unknown>:0 
  at Syncfusion.Blazor.Navigations.SfToolbar.OnAfterScriptRendered () <0x4e07530 + 0x00106> in <filename unknown>:0 
  at Syncfusion.Blazor.SfBaseComponent.OnAfterRenderAsync (System.Boolean firstRender) <0x4553280 + 0x00348> in <filename unknown>:0 
  at Syncfusion.Blazor.Navigations.SfToolbar.OnAfterRenderAsync (System.Boolean firstRender) <0x4930068 + 0x0020e> in <filename unknown>:0 
  at Microsoft.AspNetCore.Components.RenderTree.Renderer.GetErrorHandledTask (System.Threading.Tasks.Task taskToHandle) <0x404fcb0 + 0x000b6> in <filename unknown>:0 

7 Replies
SK Satheesh Kumar Balasubramanian Syncfusion Team July 15, 2020 12:45 PM UTC

Hi Brice,

 

Thanks for contacting Syncfusion support. 

 

We have checked your reported query “Random errors at startup” with provided details in the forum 156029 and but we regret to let you know that the reported issue could not be replicated at our end. Also, we have prepared a sample using package version 18.2.0.45 which can be get by the below sample Link.

 

 

Kindly check with shared sample once and get back to us with below details, if this issue may still persist 

  • Share issue replicating sample code (if possible)
  • Replicate your issue shared sample
  • Share issue depicting image/video

 

Regards,

Satheesh Kumar B


SA Sanjay July 21, 2020 12:38 PM UTC

Can confirm i also get this weird error. I have just updated my nuget from 18.1.0.59 to 18.2.0.46. 

This seems to happen when i navigate quickly. I will post a video shortly.


I have no SfToolbar in my code at all, i assume this is due to the SfGrid?


SA Sanjay July 21, 2020 12:46 PM UTC

I have attached a recording of this error happening at the end of the video.

It seems to only happen when you navigate very quickly and the SfGrid on the previous page is in a loading state.

Attachment: Error_157b4852.rar

AK Alagumeena Kalaiselvan Syncfusion Team July 22, 2020 02:27 PM UTC

Hi Brice/Sanjay, 

Thanks for your update. 

We have checked the reported error “blazor _instance of null” with Tab and Grid(which internally have Toolbar) components and we could replicate your issue at our end. So, we considered this case as defect and logged the defect report for that which can be tracked from the below link. 

We will fix this issue in our upcoming patch release which is expected to be Scheduled on end of July, 2020. 

Regards 
Alagumeena.K  


VM Vengatesh Maniraj Syncfusion Team July 29, 2020 01:10 PM UTC

Hi Brice/Sanjay,

 

We are glad to inform you, the reported defect “blazor _instance of null” with Tab and Toolbar Components have been resolved at our end. So we suggest you please upgrade the package version to the latest (v18.2.47) package to avail of this fix.

 

Nuget: https://www.nuget.org/api/v2/package/Syncfusion.Blazor/18.2.0.47

 

Regards,

Vengatesh 


AB Andre Bierwirth September 9, 2020 04:26 PM UTC

Hello,

now the exception is away, but the component does not load async. 

I have a grid with only 958 items, now it takes a little bit more than 1 second to respond on a page change.

The userexperience is very laggy with 18.2.0.57!
18.2.0.57 has other new problems with dbcontext threading.

Version 18.2.0.47 looks okay for me! 

Thank you
Andre 

AK Alagumeena Kalaiselvan Syncfusion Team September 10, 2020 01:41 PM UTC

Hi Andre,  
  
Sorry for the trouble you are facing after upgrading to our latest version.   
  
Query: “I have a grid with only 958 items, now it takes a little bit more than 1 second to respond on a page change.”  
  
We have analyzed your query and we understand that you are facing issue (while paging) in Grid after upgrading to our (18.2.0.57) latest version. We need some more details regarding the reported issue to validate at our end. So kindly share the following details.   
  
  1. Share your Grid code example .
  2. Share the details how you have bound datasource to Grid from your data base.
  3. Are your facing any exception while loading or during paging operation. If yes, share the screenshot of the error.  
  4. Share the type of your application (Blazor Server or Blazor WASM).
  5. If possible share the video demonstration of the issue along with replication procedure.
  
Above requested details will be helpful for us to validate the reported query at our end and provide solution as early as possible.    
  
Regards,  
Alagumeena.K 


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