Step by Step Tutorial

5. Includes

The site is coming together; however, there’s no way to navigate between pages. Let’s fix that.

Navigation should be on every page so adding it to your layout is the correct place to do this. Instead of adding it directly to the layout, let’s use this as an opportunity to learn about includes.

Include tag

The include tag allows you to include content from another file stored in an _includes folder. Includes are useful for having a single source for source code that repeats around the site or for improving the readability.

Navigation source code can get complex, so sometimes it’s nice to move it into an include.

Include usage

Create a file for the navigation at _includes/navigation.html with the following content:

<nav>
  <a href="/">Home</a>
  <a href="/about.html">About</a>
</nav>

Try using the include tag to add the navigation to _layouts/default.html:

<!doctype html>
<html>
  <head>
    <meta charset="utf-8">
    <title>{{ page.title }}</title>
  </head>
  <body>
    {% include navigation.html %}
    {{ content }}
  </body>
</html>

Open http://localhost:4000 in your browser and try switching between the pages.

Current page highlighting

Let’s take this a step further and highlight the current page in the navigation.

_includes/navigation.html needs to know the URL of the page it’s inserted into so it can add styling. Jekyll has useful variables available, one of which is page.url.

Using page.url you can check if each link is the current page and color it red if true:

<nav>
  <a href="/" {% if page.url == "/" %}style="color: red;"{% endif %}>
    Home
  </a>
  <a href="/about.html" {% if page.url == "/about.html" %}style="color: red;"{% endif %}>
    About
  </a>
</nav>

Take a look at http://localhost:4000 and see your red link for the current page.

There’s still a lot of repetition here if you wanted to add a new item to the navigation or change the highlight color. In the next step we’ll address this.

© 2020 Jekyll Core Team and contributors
Licensed under the MIT license.
https://jekyllrb.com/docs/step-by-step/05-includes/