Controls

First load in flight — no answer has arrived yet. Same signal the body's empty-state guard uses (body.tsx), passed here so the footer cannot claim a result count the grid does not have. Defaults to false for direct callers outside the grid.

Refetch in flight. See isLoading.

Hide the footer's selection counter because the selection action bar is already stating it. Internal: the grid decides, never a consumer.

Optional predicate override for drop-acceptance.

Default (when omitted): the toolbar calls column.getCanGroup() which checks the engine's enableGrouping option. That works for client-mode grouping, but in server-grouping mode the engine's enableGrouping is intentionally false (the engine doesn't compute its own grouped row-model; we synthesise group rows via useServerGrouping). Without an override, every drop is rejected — see ADR-014.

Pass a custom predicate when in server-grouping mode that consults column.columnDef.server?.groupBy instead of the engine flag. <ActiveGrid> wires this automatically; standalone consumers of <GroupingToolbar> only need to pass it when their grouping-source is also server-side.