ExpressionChangedAfterItHasBeenCheckedError, *ngIf, Angular7?

Question

Angular

I get an observable from the preloaderService service in quizPage, then in the page template I use the received data and display this or that content. At the same time, an error occurs non-stop:

If detectChanges is uncommented, then it stops seeing the preloaderState property in the template, saying that null does not have such a property.

Answer 1

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