columns.columns Array

The columns which will be rendered as child columns under this group column header.

Group columns cannot be data-bound and support a limited number of bound column settings such as title or locked.

Example - setting the column group column for displaying multicolumn headers

<div id="treelist"></div>
<script>
$("#treelist").kendoTreeList({
    columns: [
    {
        title: "Personal Info",
        columns: [
            { field: "lastName" },
            { field: "age" }
        ]
    },
    {
        title: "Work info",
        columns: [
            { field: "position" }
        ]
    }
  ],
  dataSource: [
      { id: 1, parentId: null, lastName: "Jackson", age: 25, position: "CEO" },
      { id: 2, parentId: 1, lastName: "Weber", age: 33, position: " VP, Engineering" }
    ]
});
</script>