Friday, February 26, 2021

How to Convert Bootstrap Pills (Tabs) Into a Dropdown Menu

In the past, we’ve discussed various Bootstrap 4 extensions. Today I’ll show you how to convert Bootstrap pills (tabs) into a dropdown. Most importantly we’ll keep both these components in sync. We’ll use pills for the desktop layout and a dropdown for mobile screens.

Note: for this exercise, I’m going to use Bootstrap 4 latest stable version (v4.6). As soon as v5 goes stable, I might revisit this topic and implement a solution for this version as well.

Our Bootstrap Extension

Check out the final demo! Click on a dropdown item to see how the corresponding tab panel appears. Additionally, open the demo and check its layout on a large screen. You’ll see that pills replace the dropdown without changing the active panel.

Here’s how they appear in their two states:

Bootstrap dropdown to pills or tabs

Why do this? By default Bootstrap tabs and pills don’t have responsive behavior, other than stacking/wrapping. A dropdown menu is a far more elegant solution for small screens.

Bootstrap Tabs and Pills

Bootstrap tabs help us divide content into multiple sections that live under a common parent. At any given time only one of these sections is visible. Imagine them like browser tabs; the difference being that you don’t have to change the page to view them all.

Bootstrap tabs

Bootstrap pills are essentially just tabs with a different layout. 

Bootstrap pills

For this example, we’re going to use pills. However, you can just as easily use tabs instead. All you have to do is to change the tabs-related markup/classes with the pills-related one(s).

1. Include Bootstrap Assets

To kick things off, we’ll include the required CSS and JavaScript files within our Codepen demo:

The required Bootstrap CSS file
The required Bootstrap CSS file
The required Bootstrap JavaScript files
The required Bootstrap JavaScript files

2. Build the Project Layout

Our project on medium screens and above (≥768px) will look like this:

The project layout on desktop screens

Here we’ll have a container that will include:

  • The pills.
  • The content for each pill (tab panels).
  • The social links.

The required markup:

The majority of this markup comes from Bootstrap documentation, just a few things have changed.

On smaller screens (<768px), we’ll replace the pills with a dropdown like this:

The project layout on mobile screens

But, here’s the interesting thing: if you check the markup above, you’ll notice that we haven’t defined any dropdown component. We’ll dynamically include it on the page through JavaScript.

3. Add Some Basic Styles

Next, we’ll specify some basic styles for our project. Pretty simple stuff. We’ll only override some of Bootstrap default styles to fit our layout. For example, we’ll change the aesthetics of the pills and give .container-fluid  a maximum width of 1250px.

The styles:

4. Add the JavaScript

We’ll start by looping through all .tabs-to-dropdown elements, and for each one of them, several actions will take place:

Note #1: we’ll use a loop here as we assume that our page can contain more than one .tabs-to-dropdown element.

Multiple tabs

Note #2: in the code above, first we’ll create the dropdown, then we’ll reference it. That’s why the generateDropdownMarkup() function comes before the dropdown-related variables. 

Create the Dropdown Component

First, we’ll call the generateDropdownMarkup() function and pass to it the related .tabs-to-dropdown element.

Here’s the function declaration:

This function will generate the code for the dropdown toggle component and prepend it to the .nav-wrapper element. To achieve this, inside this function, we’ll call the generateDropdownLinksMarkup() one that will be responsible for creating the dropdown menu items. Their text will match the text of the corresponding pills. 

Here’s the function declaration:

After executing these functions, the dropdown markup will look like this:

The dropdown markup

Hide Duplicated Menu Item

Each time we open the dropdown, we should prevent the toggle button also appearing as a menu item. So, instead of this:

We want this:

In this scenario, when the “Company” tab panel is active, the “Company” menu item should be hidden.

To implement this functionality, we’ll take advantage of the show.bs.dropdown event that Bootstrap provides:

Inside the callback function, we’ll do the following things:

  • Grab the text of the toggle button.
  • Loop through the menu links and consider if their text matches the button’s text.
  • If this is the case, they will receive the d-none class. Otherwise, they will lose this one.

Synchronize Dropdown With Pills

The last and most challenging step is to synchronize the dropdown and pills. 

Synchronize tabs and dropdown

So first, each time we click on a dropdown menu item, the corresponding tab panel should appear.

Here’s the required code:

Inside the callback function, we’ll do the following things:

  • Grab the index and text of the target/active link.
  • Replace the toggle button text with the text of the active link.
  • Select the pill whose index matches the index of the active link and show its associated panel.

Then, each time we click on a pill, the toggle button text should change and match the text of the appropriate pill.

To implement this functionality, we’ll take advantage of the shown.bs.tab event that Bootstrap provides:

Inside the callback function, we’ll do the following things:

  • Grab the index of the active pill.
  • Grab the text of the dropdown menu item whose index matches the index of the active pill.
  • Replace the text of the dropdown toggle button with the text of the corresponding menu item.

Conclusion

That’s all, folks! Thanks for following along with another Bootstrap 4 tutorial. Hopefully, this extension gave you an idea about how to handle pills in a mobile layout. As you saw, converting them into a fully functional dropdown component isn’t as difficult as it might appear.

Go ahead and do the same work with the tabs this time!

If you found this solution helpful or in case you have any questions, drop me a line! Plus, let me know if you want to see any other Bootstrap extensions.

Here’s a reminder of our extension:

As always, thanks a lot for reading!

Bootstrap Tutorials and Resources

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