Guide

Taxonomy Index List Controller

Container block that renders taxonomy navigation lists. On desktop, displays taxonomy lists in a grid layout. On mobile, automatically converts the structure into WordPress core accordions (core/accordion with core/accordion-item / core/accordion-heading / core/accordion-panel). Handles reusable block references and extracts sub-heading labels for accordion titles.

Namespace

prc-block/taxonomy-index-list-controller

Category

theme

Inserter preview

block.json includes an example that mirrors the default grid template: grid-controller with three grid-column blocks (gridLayout including mobileSpan, allowedBlocks for taxonomy-list and core/block). This drives the inserter preview.

Supports

FeatureDetail
AnchorYes
HTMLNo
SpacingblockGap, margin (top/bottom only), padding
TypographyfontSize, fontFamily

Attributes

AttributeTypeDefaultDescription
allowedBlocksarray—Restricts which block types can be inserted as inner blocks
orientationstring"vertical"Layout orientation of the taxonomy index

Available Styles

None declared in block.json.

Inner Blocks

Accepts inner blocks. Typically contains prc-block/grid-controller with prc-block/grid-column children holding prc-block/taxonomy-list blocks or reusable block references (core/block).

Parent / Ancestor Requirements

None.

Context

None declared.

Usage

Insert the Taxonomy Index List Controller to create a structured taxonomy navigation. The block wraps taxonomy list blocks in a grid layout for desktop and converts them to an accordion on mobile.

The block handles two content patterns:

  • Direct taxonomy lists: prc-block/taxonomy-list blocks placed in grid columns.
  • Reusable block references: core/block (wp_block post type) references that contain taxonomy lists, resolved at render time.

On mobile, sub-heading labels (from prc-block/taxonomy-list-link blocks with is-style-sub-heading variation) are extracted to become accordion section titles, and a "Main {label} page" link is prepended to each accordion section.

Requirement: The host WordPress version must register core/accordion and related blocks (same serialized markup as core’s block library fixtures: <!-- wp:accordion -->, <!-- wp:accordion-item -->, etc.).

Block Markup (save)

Standard inner blocks save. On mobile, the server render callback does not use the saved grid markup as-is: it rebuilds serialized core/accordion markup (see Mobile: core accordion serialized markup below).

PHP Rendering

class-taxonomy-index-list-controller.php (PRC\Platform\Blocks\Taxonomy_Index_List_Controller)

Key methods:

  • render_reusable_block($attributes) — Resolves core/block (wp_block) references. Detects when a reusable block contains a single prc-block/taxonomy-list and routes it through accordion conversion for mobile, wrapping the result in core/accordion.
  • parse_taxonomy_list_as_accordion($taxonomy_list_block) — Extracts the is-style-sub-heading inner block's label as the accordion title. Removes the sub-heading block from the content, prepends a "Main {label} page" link to the remaining items when a URL exists, and returns serialized core/accordion-item markup (heading + panel + inner blocks).
  • render_as_accordion_block($block) — Iterates through the grid > column > inner block hierarchy, converting each taxonomy list into an accordion item. Wraps all items in core/accordion. Uses parse_blocks() and render_block() for output.
  • render_block_callback() — Entry point. Uses PRC\Platform\get_current_device() for mobile detection. On desktop, renders inner blocks normally. On mobile, delegates to render_as_accordion_block().

Mobile: core accordion serialized markup

PHP builds strings that match the shape of core serialized block HTML (see WordPress core__accordion*.serialized.html fixtures in Gutenberg): short block names in comments (accordion, accordion-item, accordion-heading, accordion-panel).

For each taxonomy list:

  1. core/accordion-item — Contains a core/accordion-heading block (title in the toggle markup) and a core/accordion-panel whose inner content is serialize_blocks() output for the taxonomy list links (including the optional "Main {label} page" link block).
  2. core/accordion — Wraps one or more accordion items in <div role="group" class="wp-block-accordion">…</div>. The wrapper block is serialized with style.typography.fontFamily set to the theme preset var:preset|font-family|sans-serif (Franklin Gothic stack in prc-design-system theme.json) so the accordion uses sans-serif typography.

Styling otherwise follows core/theme.json + global styles for core/accordion.

Frontend Interactivity

No Interactivity API store is registered by this block. Desktop rendering uses standard HTML links. On mobile, behavior comes from WordPress core accordion block scripts (viewScriptModule on core/accordion).

BlockRelationship
prc-block/taxonomy-listPrimary child block containing taxonomy term links
prc-block/taxonomy-list-linkIndividual term link within taxonomy lists
core/accordionMobile wrapper for converted taxonomy sections
core/accordion-itemOne mobile section per taxonomy list
core/accordion-headingSection title (from sub-heading label)
core/accordion-panelPanel body containing link blocks
prc-block/grid-controllerGrid layout container for desktop
prc-block/grid-columnGrid column children in desktop layout
core/blockReusable block references resolved at render time

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