Get number of visible rows

I have a grid that does not use paging but is in a scroll-able div.  I would like to know the number of rows in the grid that are visible.  I know I can query against the data source but If I filter I would like the filtered count.  I have created a record navigation pane that when a row is selected additional details are provide.  My record navigation pane has a next and previous with a first and last button.  I need to know how many records so I can display record number: 4 of 15 or 4 of 500.

<template>      ...  </template>    <script>  ...  export default {    ...   methods: {      btnClick(args) {        var buttonText = args.target.innerText;        let rows = this.$refs.grid.ej2Instances.getSelectedRowIndexes();        let index = rows[0];        let lastIndex = this.$refs.grid.ej2Instances.getRows().length - 1;        switch (buttonText) {          case "FIRST":            this.$refs.grid.ej2Instances.selectRow(0, true);            break;          case "NEXT":            this.$refs.grid.ej2Instances.selectRow(index + 1, true);            break;            case "PREV":            this.$refs.grid.ej2Instances.selectRow(index - 1, true);            break;            case "LAST":            this.$refs.grid.ej2Instances.selectRow(lastIndex, true);            break;            default:            console.log();        }      }    },  };  </script>  ...