extra Boolean (default: true)

If set to true the filter menu allows the user to input a second criterion.

Example - disable the extra filtering criteria

<div id="filter-menu">(age filter)</div>
<br /><br />
<div id="grid"></div>
<script>
  var data = [
      { name: "Jane Doe", age: 30 },
      { name: "John Doe", age: 33 }
    ];

  var dataSource = new kendo.data.DataSource({
    data: data
  });

  $("#filter-menu").kendoFilterMenu({
    dataSource: dataSource,
    field: "age",
    extra: false
  });

  $("#grid").kendoGrid({
    columns: [
      { field: "name" },
      { field: "age" }
    ],
    dataSource: dataSource
  });
</script>