Nested List

The Nested List is a list with hierarchical levels, organized in a tree format. The user navigates through levels until reaching the desired option — ideal for classifications with subdivisions such as NAICS codes, product categories, or organizational structures.

Structure

Each list option can contain sub-options, forming a tree of unlimited depth. Options are displayed in an expandable format — the user clicks to open the lower levels.

Each option displays:

• Code — the level's numeric identifier (highlighted in different colors by depth).
• Name — the option text.
• Counter — the number of direct sub-options.

Select only last-level options

The Select Only Last-Level Options setting, when enabled, prevents the user from selecting intermediate options (such as parent categories). Only options that have no sub-options can be selected.

This is useful when the upper levels serve only for organization and navigation, and the valid selection is always the most specific one.

Practical example

A NAICS classification list (North American Industry Classification System):

• 11 — Agriculture, Forestry, Fishing and Hunting
  • 111 — Crop Production
    • 1111 — Oilseed and Grain Farming
      • 11111 — Soybean Farming
        • 111110 — Soybean Farming (selectable option with "last level" enabled)

Import and export

The Import, Export, and Expand buttons let you, respectively, import options in bulk, export the full list, and expand the entire tree for viewing.

Import is especially useful for large lists with many levels, such as official classification tables.