ng-on-destroy.js

export class tasksList {
  
  constructor(ElementRef: ElementRef) {
    this.element = ElementRef.nativeElement;
  }
  
  // ...
  
  ngOnDestroy() {
    if (this.elLists) {
      Array.prototype.forEach.call(this.elLists, (elList) => {
        $(elList).sortable('destroy');
      });
    }
  }
}