apply<T extends DataGridRow> method

@override DataGridState<T>? apply<T extends DataGridRow>(EventContext<T> context)

Apply this event's transformation to the state. Returns the new state, or null if no state change should occur. Can return a Future for async operations.

Implementation

@override
DataGridState<T>? apply<T extends DataGridRow>(EventContext<T> context) {
  if (context.state.selection.mode == SelectionMode.none) {
    return null;
  }

  final focusedRowId = context.state.selection.focusedRowId;
  if (focusedRowId == null) {
    if (context.state.displayOrder.isEmpty) return null;
    final firstRowId = context.state.displayOrder.first;
    return context.state.copyWith(
      selection: context.state.selection.copyWith(
        focusedRowId: firstRowId,
        selectedRowIds: {firstRowId},
      ),
    );
  }

  final currentIndex = context.state.displayOrder.indexOf(focusedRowId);
  if (currentIndex >= context.state.displayOrder.length - 1) return null;

  final newRowId = context.state.displayOrder[currentIndex + 1];
  return context.state.copyWith(
    selection: context.state.selection.copyWith(
      focusedRowId: newRowId,
      selectedRowIds: {newRowId},
    ),
  );
}