Joel Ross
Spring 2024

CSS Frameworks: Bootstrap

View of the Day

  • Q&A (time to review!)

  • Bootstrap Demo (code together!)

    • Utility Classes
    • Responsive CSS
    • Interactive Widgets

Q&A / Review

https://pollev.com/joelross

Updating Lecture Code

# switch to starter branch to get new starter code
git checkout starter

# download new starter code
git pull

# switch back to main branch for coding
git checkout main

# merge in new starter code (use default msg)
git merge starter --no-edit

# code and enjoy!

Get the starter code from the starter branch, but do all of your work on main.

CSS Frameworks

A CSS Framework is a collection of CSS rules published and made available for you to use. So rather than writing your own rules, you just use the ones provided to you.

 

Bootstrap is the oldest and most popular CSS framework. Created by Twitter in 2011. 

Link the Framework

<head>
  <!--... other elements here...-->

  <!-- link Bootstrap -->
  <link rel="stylesheet" 
        href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.3/dist/css/bootstrap.min.css">

  <!-- link own stylesheets AFTER framework -->
  <link rel="stylesheet" href="css/my-style.css">
</head>

minified CSS file!

https://getbootstrap.com/

Add Bootstrap to your page by including a <link> to the CSS file. This is usually loaded from a Content Delivery Network (CDN) site.

CDN

Utility Classes

Bootstrap provides rules that apply to particular classes. Give an element that class in order to style it in a certain way.

Utility Classes

For more utility classes, check the Bootstrap Documentation

https://getbootstrap.com/docs

Responsive Utilities

Bootstrap has responsive versions of most utility classes. These class names include a infix indicating at which size (or larger) the styling should apply.

Bootstrap Grids

row

row

column

column

column

Grid Columns

There are 12 columns in the grid

Elements can take up many columns

Row 1:

Row 2:

Row 3:

Specify columns based on screen-size

Smaller screen display

A Row:

Interactive Widgets

The Bootstrap framework provides some interactive "widgets" you can use without writing separate JavaScript code, just by using specific HTML attributes.

https://getbootstrap.com/docs/5.3/components

 

You will need to add Bootstrap's JavaScript code to your page by including a <script> tag in your <head>

 

<head>
  <!-- include Bootstrap library (before your script!) -->
  <!-- copy script tag from the Bootstrap home page -->
  <script src="https://cdn.jsdelivr.net/npm/bootstrap@5.3.3/dist/js/bootstrap.bundle.min.js"></script>
</head>

Example: Collapsables

As a simple example, you can make an element "collapsable" so that it disappears with a button click!

https://getbootstrap.com/docs/5.0/components/collapse/

<button class="btn btn-primary" 
        data-bs-toggle="collapse" 
        data-bs-target="#collapseExample" 
        aria-expanded="false" aria-controls="collapseExample">
   Button with data-bs-target
</button>


<div class="collapse" id="collapseExample">
    Some placeholder content for the collapse component. This panel is 
    hidden by default but revealed when the user clicks the toggler.
</div>

aria for screen-readers

Example: NavBar

See https://getbootstrap.com/docs/5.3/components/
navbar/#toggler for an example of a NavBar with a collapsible "hamburger menu"

Action Items!

  • Read: through Chapter 10​

    • ​Now is a good time to catch up!

  • Problem Set 03 due TONIGHT

  • Problem Set 04 due next Wednesday
  • Project Draft 1 due week from Sunday
     

Next: JavaScript!!