All datasources done. Now to wire them up in the components.

Plus ElementRefs are now optional as they cannot be initialized

overlord/src/app/stock-movement/stock-movement.component.ts

@@ -14,8 +14,8 @@ import { StockMovementDataSource } from './stock-movement-datasource';
   styleUrls: ['./stock-movement.component.css'],
 })
 export class StockMovementComponent implements OnInit {
-  @ViewChild(MatPaginator, { static: true }) paginator: MatPaginator;
-  @ViewChild(MatSort, { static: true }) sort: MatSort;
+  @ViewChild(MatPaginator, { static: true }) paginator?: MatPaginator;
+  @ViewChild(MatSort, { static: true }) sort?: MatSort;
   dataSource: StockMovementDataSource;
   form: FormGroup;
   info: StockMovement;