Why you should migrate from Bootstrap 3 to Bootstrap 4

Recently we at Explara decided to change our Frontend codebase from Bootstrap 3 to Bootstrap 4 ,work is still in process which’ll come out soon with new UI and all Frontend stacks’ll be written in Bootstrap 4.As i lately heard lot of people asking about why to migrate from Bootstrap 3 to Bootstrap 4 where our old code totally working ?? like it’s the same discussion every time we upgrade our tech stack.So i’m gonna elaborate what’r the benefits of Bootstrap 4.

Bootstrap is one of the most popular for developing responsive web applications.It’s an open source, easy to work with a framework that saves plenty of time.Bootstrap 4 has come with major and exciting changes with it.If u ask me personally what u love about it? I’m totally gonna say Flexbox as it’s grid system.

Flexbox

With Bootstrap 4 , Bootstrap is flexbox by default. Flexbox is a powerful tool that gives great flexibility and control to the components and their layout. It is an excellent tool for responsive web design. It provides a flexible container that adjusts its size, regardless of the size of the content to fill the available space.

Most components in Bootstrap 4 utilizes flexbox. This makes it possible to not use display:inline hacks and floats and therefore confusion clearfix. Every time u want make an element in a row make it center of height we have toto write bunch of code and bunch of hacks.

Flexbox gives you the power to create:

  • grid columns of equal width and auto spacing
  • equal height and equal width cards
  • auto margin for easy spacing
  • justified navigation and button groups

What Is Different In Version 4 :

Now we can begin to talk about the new features of Bootstrap 4. As technology rapidly evolves, newer and smarter languages are developed to make building clean, fast websites much simpler. Such is the case with the newest release of Bootstrap. version 4 is a major rewrite of almost the entire project. We will summarise some key changes of this improved.

Global Changes:

  • Switched from Less to Sass for source CSS files.
  • Switched frompx to rem as Bootstrap’s primary CSS unit, though pixels are still used for media queries and grid behavior as device viewports are not affected by type size.
  • Global font-size increased from 14px to 16px.
  • Added a new grid tier for ~480px and below.

Grid system:

Bootstrap 4’s major step towards improvement is its movement towards adopting Flexbox. As part of flexbox, included support for vertical and horizontal alignment classes. Bootstrap 4 positions a lot of emphasis on customization. It’s new grid tier system lets the Bootstrap 4 enjoy the presence of up to 5 grid tiers ( example of 5 tiers : .col-4, .col-sm-4, .col-md-4, .col-lg-4, .col-xl-4 ). One can easily say that Bootstrap 4 provides access to an improved grid system.

  • Added a new sm grid tier below 768px for more granular control. There is now xs, sm, md, lg, and xl. This also means every tier has been bumped up one level (so .col-md-6 in v3 is now .col-lg-6 in v4).
  • Changed grid system media query breakpoints and container widths to account for new grid tier and ensure columns are evenly divisible by 12 at their max width.
  • Grid breakpoints and container widths are now handled via Sass maps ($grid-breakpoints and $container-max-widths) instead of a handful of separate variables. These replace the @screen-* variables entirely and allow you to fully customize the grid tiers.
  • Media queries have also changed. Instead of repeating media query declarations with the same value each time, there is now @include media-breakpoint-up/down/only. Now, instead of writing @media (min-width: @screen-sm-min) { … }, you can write @include media-breakpoint-up(sm) { … }.

Auto layout column example

All the column auto calculates it’s width.Image Credit: bootstrap4
<div class="container">
<div class="row">
<div class="col">
1 of 2
</div>
<div class="col">
2 of 2
</div>
</div>
<div class="row">
<div class="col">
1 of 3
</div>
<div class="col">
2 of 3
</div>
<div class="col">
3 of 3
</div>
</div>
</div>

Setting one column width example

one column has wider specified width.Image Credit: bootstrap4
<div class="container">
<div class="row">
<div class="col">
1 of 3
</div>
<div class="col-6">
2 of 3 (wider)
</div>
<div class="col">
3 of 3
</div>
</div>
<div class="row">
<div class="col">
1 of 3
</div>
<div class="col-5">
2 of 3 (wider)
</div>
<div class="col">
3 of 3
</div>
</div>
</div>

Variable width content example

column has Variable width content.Image Credit: bootstrap4
<div class="container">
<div class="row justify-content-md-center">
<div class="col col-lg-2">
1 of 3
</div>
<div class="col-md-auto">
Variable width content
</div>
<div class="col col-lg-2">
3 of 3
</div>
</div>
<div class="row">
<div class="col">
1 of 3
</div>
<div class="col-md-auto">
Variable width content
</div>
<div class="col col-lg-2">
3 of 3
</div>
</div>
</div>

Browser Support:

Dropped IE8 and iOS 6 support. v4 is now only IE9+ and iOS 7+. For sites needing either of those, use v3.

Utility classes:

In Bootstrap 4, new utility classes have been included without hampering any existing functionality, whatsoever. Such important additions are as that of responsive text alignment classes, responsive floats, and responsive embedding. Apart from offering many shortcuts, these, respectively, allow for changing the alignment of the text, floating of the elements and the scaling of the aspect ratio of any embedded media. (example:.hidden-md-up hides an element on medium, large, and extra-large viewports. Now, instead of .hidden-md-up, use .d-md-none).

Images:

  • Renamed .img-responsive to .img-fluid.
  • Renamed .img-rounded to .rounded
  • Renamed .img-circle to .rounded-circle

Tables:

  • Responsive tables no longer require a wrapping element. In simple words, in Bootstrap 3, .table-responsive class should be added to the parent <div>. But in Bootstrap 4 , .table-responsive class to be added to <table> element.
  • Added a new .table-inverse option.
  • Added table header modifiers: .thead-default and..thead-inverse
  • Renamed contextual classes to have a .table--prefix. Hence,.active .success.warning.danger and .table-info to .table-active.table-success.table-warning.table-danger and .table-info.

Navigation:

In Bootstrap 4, Navigation component has been simplified to a great extent. One is required to create a new list of elements employing the latest nav base class. There are some recent additions like nav-link class, nav-item class, and navigation bar styles also.

  • Rewrote component with flexbox.
  • .navbar-default is now .navbar-light, though .navbar-dark remains the same. However, these classes no longer set background-colors; instead they essentially only affect color.
  • .navbar-toggle is now .navbar-toggler and has different styles and inner markup (no more three <span>s).
  • Dropped the .navbar-form class entirely. It’s no longer necessary; instead, just use .form-inline and apply margin utilities as necessary.
  • Navbars no longer include margin-bottom or border-radius by default.

Tooltips and Popovers

Bootstrap 4 uses a powerful third party library called tether for positioning of components in relation to one another on a web page. It provides improved auto-placement of tooltips and popovers.

Tether is a third party JavaScript library. It has to be included in the HTML using a <script> tag before adding your bootstrap.js file.

Should we migrate to Bootstrap 4 or remain on Bootstrap 3

We have talked about the features that Bootstrap 4 offers. We can see there has been a lot of work is done in optimizing and cleaning up unnecessary elements and classes throughout the entire framework. Bootstrap 4 promises to be much quicker and streamlined for even greater flexibility and ease when creating an awesome mobile-friendly website.

Bootstrap 4, moved to flexbox. This can be considered as one of the biggest and significant achievements. This will provide the following benefits:

  • Flexbox based grid
  • New XLl grid tier
  • Latest auto-layout grid
  • Navbar customisation options
  • New Spacing utilities
  • Sans Glyphicons configuration (Bloat-free zone)
  • Responsive sizing
  • Responsive Floats
  • Auto Margins
  • Vertical Centering

Conclusion

Bootstrap has many more changes and improvements in store in terms of typography, styles, and layouts of components. To understand all the changes made try to go through the documentation on their official website It will definitely improve the development and user experience of a responsive website.