# collapseTreeLevel( rrn )

This method collapses the tree level at the specified row, which is considered the "parent" row. All "child" rows belonging to that parent row will be collapsed (hidden).

**Parameters:**

rrn - relative record number of the row for which to collapse the tree level, where 1 is the first row, 2 is the second row, etc. If 0 is specified, then all rows will be collapsed.

*Row n refers to the original row number as written by the server-side program, and does not change when filters or sorts are applied.

Please see here for a grid tree example.

**Example:**

```
// collapse the tree level for first row
getObj("Grid1").grid.collapseTreeLevel(1);
```

This function first appeared in Profound UI 6.18.0