Understanding Bootstrap Modals

In my previous tutorial, I explained how powerful Bootstrap 3 CSS framework is for a novice designers. It ships with some of the best ready-to-use JavaScript and jQuery components and plugins. The framework has reached version 3.3.7 and it’s getting ready for the release of v.4 beta, which will bring about several important and necessary changes.

In this tutorial we will be talking about one of the most useful jQuery Bootstrap plugins, The Modal.

The Bootstrap Modal is a lightweight multi-purpose JavaScript popup that is customizable and responsive. It can be used to display alert popups, videos, and images in a website. Websites built with Bootstrap can use the modal to showcase (for example) terms and conditions (as part of a signup process), videos (similar to a standard light box), or even social media widgets.

Now let’s examine the different parts of Bootstrap’s modal, so we can understand it better.

The Bootstrap Modal is divided into three primary sections: the header, body, and footer. Each has its own significance and hence should be used properly. We’ll discuss these shortly. The most exciting thing about Bootstrap’s modal? You don’t have to write a single line of JavaScript to use it! All the code and styles are predefined by Bootstrap. All that’s required is that you use the proper markup and the attributes to trigger it.


The Default Modal

The default Bootstrap Modal looks like this:

Default Bootstrap modal

To trigger the modal, you’ll need to include a link or a button. The markup for the trigger element might look like this:

[code language=”html”]
<a href=”#” class=”btn btn-lg btn-success”
data-target=”#basicModal”>Click to open Modal</a>

Notice the link element has two custom data attributes: data-toggle and data-target. The toggle tells Bootstrap what to do and the target tells Bootstrap which element is going to open. So whenever a link like that is clicked, a modal with an id of “basicModal” will appear.

Now let’s see the code required to define the modal itself. Here is the markup:

[code language=”html”]
<div class=”modal fade” id=”basicModal” tabindex=”-1″ role=”dialog” aria-labelledby=”basicModal” aria-hidden=”true”>
<div class=”modal-dialog”>
<div class=”modal-content”>
<div class=”modal-header”>
<button type=”button” class=”close” data-dismiss=”modal” aria-hidden=”true”>&amp;times;</button>
<h4 class=”modal-title” id=”myModalLabel”>Modal title</h4>
<div class=”modal-body”>
<h3>Modal Body</h3>
<div class=”modal-footer”>
<button type=”button” class=”btn btn-default” data-dismiss=”modal”>Close</button>
<button type=”button” class=”btn btn-primary”>Save changes</button>

The parent div of the modal should have the same id as used in the trigger element above. In our case it would be id="basicModal".

Note: Custom attributes like aria-labelledby and aria-hidden in the parent modal element are used for accessibility. It is a good practice to make your website accessible to all, so you should include these attributes since they won’t negatively affect the standard functionality of the modal.

In the modal’s HTML, we can see a wrapper div nested inside the parent modal div. This div has a class of modal-content that tells bootstrap.js where to look for the contents of the modal. Inside this div, we need to place the three sections I mentioned earlier: the header, body, and footer.

The modal header, as the name implies, is used to give the modal a title and some other elements like the “x” close button. This should have a data-dismiss attribute that tells Bootstrap which element to hide.

Then we have the modal body, a sibling div of the modal header. Consider the body an open canvas to play with. You can add any kind of data inside the body, including a YouTube video embed, an image, or just about anything else.

Lastly, we have the modal footer. This area is by default right aligned. In this area you could place action buttons like “Save”, “Close”, “Accept”, etc., that are associated with the action the modal is displaying.

Now we are done with our first modal! You can check it out on our demo page.

Changing the Modal’s Size

Continue reading %Understanding Bootstrap Modals%

Source: Sitepoint