Page Toc Plugin (Anchors + Table of Contents)

The Page Toc Plugin is for Grav CMS that generates anchors based on HTML header tags, and can also create a table of contents from those headers.

With version 3.0 this plugin is able to automatically generate anchor links with hover-click capability without the need for other plugins (such as the anchors plugin). This functionality operates independently from the now optional "table of contents" functionality.

Installation

Installing the Page Toc plugin can be done in one of two ways. The GPM (Grav Package Manager) installation method enables you to quickly and easily install the plugin with a simple terminal command, while the manual method enables you to do so via a zip file.

GPM Installation (Preferred)

The simplest way to install this plugin is via the Grav Package Manager (GPM) through your system's terminal (also called the command line). From the root of your Grav install type:

bin/gpm install page-toc

This will install the Page Toc plugin into your /user/plugins directory within Grav. Its files can be found under /your/site/grav/user/plugins/page-toc.

Manual Installation

To install this plugin, just download the zip version of this repository and unzip it under /your/site/grav/user/plugins. Then, rename the folder to page-toc. You can find these files on GitHub or via GetGrav.org.

You should now have all the plugin files under

/your/site/grav/user/plugins/page-toc

Configuration

Before configuring this plugin, you should copy the user/plugins/page-toc/page-toc.yaml to user/config/plugins/page-toc.yaml and only edit that copy.

Here is the default configuration and an explanation of available options:

enabled: true               # Plugin enabled
include_css: true           # Include CSS
active: true                # Anchor IDs processed and generated for all pages
start: 1                    # Start header tag level (1 = h1) for TOC
depth: 6                    # Depth from start (2 = 2 levels deep) for TOC
hclass:                     # Custom Header TOC styling classes
anchors:                    # Anchor configuration
  start: 1                  # Start header tag level (1 = h1)
  depth: 6                  # Depth from start (2 = 2 levels deep)
  link: true                # Enabled auto-generation of clickable link with fragment
  aria: Anchor              # Aria label to use
  class:                    # Custom Header anchor styling classes
  icon: '#'                 # Icon to use, can be a symbol, emoji, ascii etc.
  position: after           # Position to put the anchor, `before|after`
  copy_to_clipboard: true   # Copy to clipboard functionality (coming soon)
  slug_maxlen: 25           # Max length of slugs used for anchors
  slug_prefix:              # A prefix used in front of generated slugs

You can now have page-toc automatically add anchors without there being a table of contents being used, just ensure active to true.

By default, The plugin is active and will add header id attributes anchors for each header level found in a page. You can set active: false and then activate on a page basis by adding this to the page frontmatter:

page-toc:
  active: true

You can also configure which header tags to start and depth on when building the id attribute anchors by changing the start and depth values. This can also be done on a per-page basis.

For example if you had a start of 3 and a depth of 3 you would get a TOC for h3, h4, and h5.

Usage

Shortcode-like syntax in your content

You can use the following shortcode-like syntax in your content:

[TOC] or [TOC/] or [toc] or [toc /]

This will replace the shortcode syntax with the Table of Contents with the components/page-toc.html.twig Twig template. Either the default one included in the page-toc plugin or an overridden version from your theme.

For example in Quark theme, you will need to create a folder called components/ under templates/ so the file will be copied to:

user/themes/quark/templates/components/page-toc.html.twig

NOTE: It's not required to set the TOC plugin active if you use the shortcode syntax in your content. That is a good enough indication that you want the plugin to be active.

Customizing specific anchors

There are situations where you want to have absolute control over the exact anchor link rather than letting page-toc create one for you. The best way to achieve this is to add your own id attribute to the header tag. This can be done either via HTML in your markdown directly:

<h2 id="my-custom-anchor">H2 Header</h2>

Or via using the header shortcodes. This approach is particularly useful if you have markdown inside your header tag:

[h2 id="my-custom-anchor"]H2 _header_[/h2]

If an id is found in one of the header tags that page-toc is configured to use for anchors, then it will use the provided value for the anchor id.

Anchor Shortcode

Page TOC now includes a anchor shortcode that allows you to manually add linkable fragments in your content.
The shortcode will automatically generate the link if no options are provided. Alternatively you can use the bbode syntax of anchor="some-custom-id" or you can explicity set it. You can also set a prefix and let the shortcode autogenerate the rest.

For example:

Ut sed nisl suscipit metus sollicitudin [anchor]<span>ornare</span>[/anchor] nec vitae nulla. In pretium massa ex, in [anchor="vulputate"]vulputate tellus[/anchor] accumsan vel. 

Nullam [anchor id="tempor"]tempor quis lorem[/anchor] venenatis finibus. Curabitur dapibus nulla sed tristique pretium. Nullam tempor quis [anchor prefix="sec2.2-"]lorem venenatis finibus[/anchor].

An example of the resulting HTML link looks like:

<a id="tempor" href="#tempor" class="inline-anchor" aria-label="Anchor">tempor quis lorem</a>

The inline-anchor CSS class is used by shortcodes and any manually generated elements so it can be styled as independently from other links or anchored headers.

Twig Templating

When the plugin is active it will add anchors to the header tags of the page content as configured. You can simply include the provided Twig template:

{% block content %}
	{% include 'components/page-toc.html.twig' %}
	{{  content|raw }}
{% endblock %}

You can also add your Table of Contents HTML in your Twig template directly with the provided toc() Twig function:

For example:

{% if active or toc_config_var('active') %}
<div class="page-toc">
    {% set table_of_contents = toc(page.content) %}
    {% if table_of_contents is not empty %}
    <h4>{{ 'PLUGIN_PAGE_TOC.TABLE_OF_CONTENTS'|t }}</h4>
    {{ table_of_contents|raw }}
    {% endif %}
</div>
{% endif %}

The toc_ordered() Twig function does the same things as a the toc() function, except it uses an ordered list instead of an unordered one.

or via the toc_items() function which rather than returning HTML directly returns objects and you can manipulate the output as needed:

{% macro toc_loop(items) %}
    {% import _self as self %}
    {% for item in items %}
        {% set class = loop.first ? 'first' : loop.last ? 'last' : null %}
        <li {% if class %}class="{{ class }}"{% endif %}>
            <a href="{{ item.uri }}">{{ item.label }}</a>
            {% if item.children|length > 0 %}
                <ul>
                    {{ _self.toc_loop(item.children) }}
                </ul>
            {% endif %}
        </li>
    {% endfor %}
{% endmacro %}

{% if config.get('plugins.page-toc.active') or attribute(page.header, 'page-toc').active %}
<div class="page-toc">
    {% set table_of_contents = toc_items(page.content) %}
    {% if table_of_contents is not empty %}
        <h4>Table of Contents</h4>
        <ul class="page-toc">
            {{ _self.toc_loop(table_of_contents.children) }}
        </ul>
    {% endif %}
</div>
{% endif %}

To explictly build a table of contents for a block of content:

{% block my_content %}
# Header 1

## Header 1.1

Nullam tempor quis lorem venenatis finibus. Maecenas ut condimentum nibh. Ut sed nisl suscipit metus sollicitudin ornare nec vitae nulla. Integer sed tortor eu ligula interdum rhoncus. Sed pulvinar ut massa et ullamcorper. Curabitur bibendum ante orci, nec porttitor dolor suscipit quis. Nulla et eros enim. 

### Header 1.1.1

Integer sed tortor eu ligula interdum rhoncus.

## Header 1.2
{% endblock %}

#### Table O' Contents
{{ toc(block('my_content'), 2, 1) }}

The add_anchors() twig funtion can take a string or a block of content and automatically adds anchors to any headers found per the configuration for the page, but you can override the start and depth. For example here we have a Twig block but we just want to add anchors to the H2 tags:

{% block my_content %}
# Header 1

## Header 1.1

Nullam tempor quis lorem venenatis finibus. Maecenas ut condimentum nibh. Ut sed nisl suscipit metus sollicitudin ornare nec vitae nulla. Integer sed tortor eu ligula interdum rhoncus. Sed pulvinar ut massa et ullamcorper. Curabitur bibendum ante orci, nec porttitor dolor suscipit quis. Nulla et eros enim. 

### Header 1.1.1

Integer sed tortor eu ligula interdum rhoncus.

## Header 1.2
{% endblock %}

#### Anchors Away!
{{ add_anchors(block('my_content'), 2, 1) }}

Limiting levels in output

As well as limiting the levels that the page TOC plugin will use in the table of contents, you can also limit the levels that are actually displayed. To do this you can pass an optional start, and depth value to the toc(), toc_ordered() , toc_items() and add_anchors() Twig functions:

{% set table_of_contents = toc(page.content, 3, 3) %}

This will only display H3 , and 3 levels deeper (up to H5) in the TOC output.

Credits

The majority of this plugin's functionality is provided by the PHP TOC Generator library by Casey McLaughlin. So Thanks for making this plugin for Grav possible!