Chart in Angular not displayed until windows resize

There’s a reason why you’re seeing that chart after resize because you’re nesting your API calls and angular change-detection doesn’t work well with nested functions. There’re 2 solutions to this problem.

1. You can flatten your API calls and remove nesting or

2. you can use changeDetectorRef to trigger the change detection by

   constructor(
             private cdr: ChangeDetectorRef
   
   ) {}
   

   use the below statement after your calculation is finished.

   this.cdr.markForCheck();

I’d advise you to go for the first option.