Cannot use 'in' operator to search for '__eventList' in null after submitting form

[Sebastian Hofmann]

Hello, I have an error and I do not know where else to look for the source, nor how to narrow down the error. Therefore, it is very likely that (unfortunately) information is missing, since I did not want to post thousands of lines of code. Please ask for the missing information. It could well be a beginner bug, as I switched from a monolithic sequential programming language to PHP and Vue or Angular only a few months ago.

But back to the topic. When I save a form an error occurs as a result.

The following two errors show up in the console:

Error 1:

Error: Uncaught (in promise): TypeError: Cannot use 'in' operator to search for '__eventList' in null TypeError: Cannot use 'in' operator to search for '__eventList' in null
  at EventHandler.addOrGetEventData (http://localhost:4200/vendor.js:12789:23)
  at EventHandler.remove (http://localhost:4200/vendor.js:12853:36)
  at Scroll.addStickyListener (http://localhost:4200/default-src_app_shared_custom-syncfusion_module_ts.js:66632:70)
  at Scroll.destroy (http://localhost:4200/default-src_app_shared_custom-syncfusion_module_ts.js:66848:12)
  at GridComponent.destroyDependentModules (http://localhost:4200/default-src_app_shared_custom-syncfusion_module_ts.js:68406:23)
  at GridComponent.destroy (http://localhost:4200/default-src_app_shared_custom-syncfusion_module_ts.js:68375:10)
  at QuestionAnswersComponent.ngOnDestroy (http://localhost:4200/src_app_modules_survey-editor_survey-editor_module_ts.js:140:62)
  at executeOnDestroys (http://localhost:4200/vendor.js:107319:20)
  at cleanUpView (http://localhost:4200/vendor.js:107202:5)
  at destroyViewTree (http://localhost:4200/vendor.js:106980:11)
  at resolvePromise (http://localhost:4200/polyfills.js:9121:19)
  at resolvePromise (http://localhost:4200/polyfills.js:9068:9)
  at http://localhost:4200/polyfills.js:9195:9 
  at _ZoneDelegate.invokeTask (http://localhost:4200/polyfills.js:8142:171)
  at Object.onInvokeTask (http://localhost:4200/vendor.js:129021:25)
  at _ZoneDelegate.invokeTask (http://localhost:4200/polyfills.js:8142:54)
  at Zone.runTask (http://localhost:4200/polyfills.js:7903:37)
  at drainMicroTaskQueue (http://localhost:4200/polyfills.js:8351:23)
  at ZoneTask.invokeTask [as invoke] (http://localhost:4200/polyfills.js:8237:11)
  at invokeTask (http://localhost:4200/polyfills.js:9661:12)

Error 2:

ERROR TypeError: Cannot use 'in' operator to search for '__eventList' in null
    at EventHandler.addOrGetEventData (ej2-base.es2015.js:4413:13)
    at EventHandler.remove (ej2-base.es2015.js:4468:40)
    at Scroll.addStickyListener (ej2-grids.es2015.js:12690:13)
    at Scroll.destroy (ej2-grids.es2015.js:12870:18)
    at GridComponent.destroyDependentModules (ej2-grids.es2015.js:14250:27)
    at GridComponent.destroy (ej2-grids.es2015.js:14225:14)
    at component-base.js:162:35
    at timer (zone.js:2405:41)
    at _ZoneDelegate.invokeTask (zone.js:406:31)
    at Object.onInvokeTask (core.mjs:26275:33)

I thought the error was coming from the  QuestionAnswersComponent.ngOnDestroy, but even when i comment out the content the error appears. At the moment the code there is:

    ngOnDestroy() {
      if (this.grid?.destroy) {
        this.grid?.destroy();
      }
    }

During the step-by-step debugging, however, it became clear that the error only occurs after this method. I was able to narrow this down to at least after the router event: ResolveEnd with a router tracing (for lack of knowledge of a better way). the next event throws is a NavigationError with the following error:

"TypeError: Cannot use 'in' operator to search for '__eventList' in null
    at EventHandler.addOrGetEventData (http://localhost:4200/vendor.js:12789:23)
    at EventHandler.remove (http://localhost:4200/vendor.js:12853:36)
    at Scroll.addStickyListener (http://localhost:4200/default-src_app_shared_custom-syncfusion_module_ts.js:66632:70)
    at Scroll.destroy (http://localhost:4200/default-src_app_shared_custom-syncfusion_module_ts.js:66848:12)
    at GridComponent.destroyDependentModules (http://localhost:4200/default-src_app_shared_custom-syncfusion_module_ts.js:68406:23)
    at GridComponent.destroy (http://localhost:4200/default-src_app_shared_custom-syncfusion_module_ts.js:68375:10)
    at QuestionAnswersComponent.ngOnDestroy (http://localhost:4200/src_app_modules_survey-editor_survey-editor_module_ts.js:141:64)
    at executeOnDestroys (http://localhost:4200/vendor.js:107319:20)
    at cleanUpView (http://localhost:4200/vendor.js:107202:5)
    at destroyViewTree (http://localhost:4200/vendor.js:106980:11)"

I would be very happy about support.

[Joseph Christ Nithin Issack]

Hi Sebastian,

  Greetings from Syncfusion support.

  Before proceeding with the solution, we would like to share the following details.

• Please share the complete grid rendering code or a simple sample to reproduce the issue.
• Please share the video demo or steps to reproduce the issue.
• Please share the Syncfusion package version you are using.

Regards,

Joseph I.