Add parameters to Data Provider for vaadin-grid

Below is the textbook data provider definition:

 dataProvider: {
            notify: true,
            value: () => {
              const _this = this;
              return (params, callback) => {
                const items = Array.apply(null, {length: params.pageSize})
                  .map((item, index) => getJSON('' + (index + * params.pageSize)));
                _this.loading = true;
                setTimeout(() => {
                  _this.loading = false;
                }, _this.delay);

in x-data-provider.html from [here]

The basic data provider fetches data when pageSize/filter/Sort properties change. In my case I have a dropdown on whose selection the vaadin grid is populated (the user can select different items and on each item there is new data in the grid). At the moment I am unable to call the the data provider whenever the user changes the drop down value.

Use Case:

Fetch Data from server when filter and sort order changed. Fetch data from server when user changes data source meaning value from drop down.

Is this possible?