rows.leavesOf() needs a source that groups in memory; this grid groups elsewhere, so it returned no rows.

Warnings reference › rows.leavesOf.unsupported

Identifier

rows.leavesOf.unsupported

Raised by

The grid (core)

Since

1.58.0

What happened

leavesOf(key) hands back the leaf rows under a group row, which the grid can only do when it did the grouping itself. This grid groups in the adapter or on the server, so the leaves are not held locally and an empty array is returned.

The fix

Use a memory source, or fetch the group's rows yourself with the group's own key as the query.

Reference

Covered in full at the API reference.