toNextPage(): Promise<any> {
     if (this.pager.isLastPage()) {
         return Promise.reject('on last');
     }
     // temp ignore pager events since we're calling requestPage manually.
     this.ignorePager();
     this.pager.increment();
     this.listenToPager();
     return this.dataSource.requestPage(this.pager);
 }

 setTimeout(() => {
     this.pager.reset();
     this.sortLocalData();
     this.dataSource.requestPage(this.pager);
 });