As soon as I add the following lines to my component (having first imported "of" from rxjs.
public children = (dataItem: any): any[] => of(dataItem.items);
public hasChildren = (dataItem: any): boolean => !!dataItem.items;
I get the folllowing error:
Type
'Observable<any>'
is missing the following properties from type
'any[]'
: length, pop, push, join, and 18 more.
How do I implement the children and hasChildren properties?