Frontend-Technology jQuery

Mastering jQuery: Simple Tricks for Success

Jay Ukani
By Jay Ukani
Aug 10, 2020
Mastering jQuery: Simple Tricks for Success

1. Back to top button

$('a.top').click(function() {

$(document.body).animate({scrollTop : 0},800);

return false;

});

//Create an anchor tag

<a class=”top” href=”#”>Back to top</a>

As you can see using the animate and scrollTop functions in jQuery we don’t need a plugin to create a simple scroll to top animation.

By changing the scrollTop value we can change where we want the scrollbar to land, in my case I used a value of 0 because I want it to go to the very top of our page, but if I wanted an offset of 100px I could just type 100px in the function.

So all we are really doing is animating the body of our document throughout the course of 800ms until it scrolls all the way to the top of the document.


2. Checking if images are loaded

$(‘img’).load(function() {

console.log(‘image load successful’);

});

Sometimes you need to check if your images are fully loaded in order to continue with your scripts, this three line jQuery snippet can do that for you easily.

You can also check if one particular image has loaded by replacing the img tag with an ID or class.

 

3. Fix broken images automatically

$('img').error(function(){

$(this).attr('src', ‘img/broken.png’);

});

Occasionally we have times when we have broken image links on our website and replacing them one by one isn’t easy, so adding this simple piece of code can save you a lot of headaches.

Even if you don’t have any broken links adding this doesn’t do any harm.

 

4. Toggle class on hover

$(‘.btn').hover(function(){

$(this).addClass(‘hover’);

}, function(){

$(this).removeClass(‘hover’);

});

We usually want to change the visual of a clickable element on our page when the user hovers over and this jQuery snippet does just that, it adds a class to your element when the user is hovering and when the user stops it removes the class, so all you need to do is add the necessary styles in your CSS file.

 

5. Disabling input fields

$('input[type="submit"]').attr("disabled", true);

On occasion you may want the submit button of a form or even one of its text inputs to be disabled until the user has performed a certain action (checking the “I’ve read the terms” checkbox for example) and this line of code accomplishes that; it adds the disabled attribute to your input so you can enable it when you want to.

To do that all you need to do is run the removeAttr function on the input with disabled as the parameter:

$('input[type="submit"]').removeAttr("disabled”);

 

6. Stop the loading of links

$(‘a.no-link').click(function(e){

e.preventDefault();

});

Sometimes we don’t want links to go to a certain page or even reload it, we want them to do something else like trigger some other script and in that case this piece of code will do the trick of preventing the default action.

 

7. Toggle fade/slide

// Fade

$( “.btn" ).click(function() {

$( “.element" ).fadeToggle("slow");

});

// Toggle

$( “.btn" ).click(function() {

$( “.element" ).slideToggle("slow");

});

Slides and Fades are something we use plenty in our animations using jQuery, sometimes we just want to show an element when we click something and for that the fadeIn and slideDown methods are perfect, but if we want that element to appear on the first click and then disappear on the second this piece of code will work just fine.

 

8. Make two divs the same height

$(‘.div').css('min-height', $(‘.main-div').height());

 

9. Self-closing elements

When inserting empty elements into the DOM, you can use self-closing tags:

$('#el1').append('<table class="holly" />');

$('#el2').before('<p class="user-message note" />');

 

10. Inserting content —Before, after, prepend or append?

When inserting elements into an element, use .prepend() or .append(). The difference is that prepend inserts the new element into the start (i.e. insert element as the first child), while append does the exact opposite, inserting the element as the last child:

$('div').prepend('<p>Hello!</p>').append('<p>Goodbye!</p>');

 

11. Loopy doopy do!

Very often people wonder how to loop through each element individually, and then target the current element. For this purpose, we can use .each() and $(this). Let’s say we want to add a class to all paragraphs, based on their index. If you are working on a static page, you might be tempted to hardcode it:

$('p').each(function (i) {

    $(this).addClass('para-' + (i+1));

}

Remember that i is a zero-based index, i.e. it starts from 0 for the first encountered element.

 

12. Automatic vendor prefixes
jQuery automatically adds vendor prefixes when it sees fit — therefore saving you the headache of adding vendor prefixes yourself:

$('.box').css({ 'transform': 'translate(100,100) scale(2)' });


13. Selectors

As previously mentioned, one of the core concepts of jQuery is to select elements and perform an action. jQuery has done a great job of making the task of selecting an element, or elements, extremely easy by mimicking that of CSS. On top of the general CSS selectors, jQuery has support for all of the unique CSS3 selectors, which work regardless of which browser is being used.

$('.feature');           // Class selector

$('li strong');          // Descendant selector

$('em, i');              // Multiple selector

$('a[target="_blank"]'); // Attribute selector

$('p:nth-child(2)');     // Pseudo-class selector


14. 'this' Selection Keyword

When working inside of a jQuery function you may want to select the element in which was referenced inside of the original selector. In this event the this keyword may be used to refer to the element selected in the current handler.

$('div').click(function(event){ 

  $(this);

});

 

15. jQuery Selection Filters

Should CSS selectors not be enough there are also custom filters built into jQuery to help out. These filters are an extension to CSS3 and provide more control over selecting an element or its relatives.

$('div:has(strong)');

 

16. Slide Demo

//HTML

<div class="panel">

  <div class="panel-stage"></div>

  <a href="#" class="panel-tab">Open <span>&#9660;</span></a>

</div>

 
//Function

$('.panel-tab').on('click', function(event){

  event.preventDefault();

  $('.panel-stage').slideToggle('slow', function(event){

    if($(this).is(':visible')){

      $('.panel-tab').html('Close <span>&#9650;</span>');

    } else {

      $('.panel-tab').html('Open <span>&#9660;</span>');

    }

  });

});

 

17. Tabs Demo

//HTML

<ul class="tabs-nav">

  <li><a href="#tab-1">Features</a></li>

  <li><a href="#tab-2">Details</a></li>

</ul>

<div class="tabs-stage">

  <div id="tab-1">...</div>

  <div id="tab-2">...</div>

</div>


// Show the first tab by default

$('.tabs-stage div').hide();

$('.tabs-stage div:first').show();

$('.tabs-nav li:first').addClass('tab-active');

// Change tab class and display content

$('.tabs-nav a').on('click', function(event){

  event.preventDefault();

  $('.tabs-nav li').removeClass('tab-active');

  $(this).parent().addClass('tab-active');

  $('.tabs-stage div').hide();

  $($(this).attr('href')).show();

});

 

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New Features and Highlights of Bootstrap 5

TAGS Front-end-Technologies jQuery
The Ultimate Guide to Bootstrap 5 Changes
Frontend-Technology
The Ultimate Guide to Bootstrap 5 Changes
Jay Ukani
Jun 29, 2020

The Bootstrap 5 alpha version has been released on June 16, 2020. You can check the official page for Bootstrap 5 alpha. Bootstrap is a free and open-source most popular CSS framework for website and web applications. It contains CSS- and (optionally) JavaScript-based design templates for typography, forms, buttons, navigation, and other interface components.HTML- and CSS-based design templates for different components of a website or application such as models, forms, buttons, navigation, accordion, tabs, typography and other interface components with helpful JavaScript extensions. A bootstrap is a powerful tool for whatever type of website and web application you are trying to build. The following are some of the expected changes in Bootstrap 5: jQuery could get removed As we all know, Bootstrap has made this decision long before. The team had opened a pull request in 2017 aiming to remove jQuery entirely from bootstrap versions, and now in bootstrap 5 alpha it is done and replaced entirely.   Switch to Vanilla JavaScript JavaScript is currently dominating the modern web development community. Almost all modern web browsers on consoles, desktops, games, tablets, and mobile phones include JavaScript interpreters. Therefore, it's geared up to become the universal scripting standard of the global.  As a result, this will improve the size and weight of the files and libraries used by the framework.   Responsive Font Sizes (RFS) Bootstrap 5 alpha enables responsive font sizes by default. That will automatically resize the typography element according to the size of the user’s viewport through RFS engine or Responsive Font Sizes. As per RFS repository, RFS is a unit resizing engine. Furthermore, RFS offers the ability to resize every value for any CSS property with units, like padding, margin, box-shadow, or border-radius.   Enhanced grid system Bootstrap 5 alpha isn’t a complete departure from v4. Developers of the first alpha have made sure that everyone can be able to upgrade to this future version more easily. Here’s a rundown of what’s new in the grid system: New grid tier: XXL ≥1400px .gutter classes have been replaced with .g* utilities. Vertical spacing classes. Columns are no longer position: relative by default. Form layout options are replaced with the new grid system. Also, options for your grid gutter spacing are added.            Here’s a quick example of how to use the new grid gutter classes: <div class="row g-5">   <div class="col">...</div>   <div class="col">...</div>   <div class="col">...</div> </div> Drop Internet Explorer 10 and 11 support Well, Internet Explorer was talk of the town when it was released as it was the only browser to support Java applets and CSS. Although it is no longer relevant with Chrome, Firefox, and Edge as it doesn’t support modern JavaScript standards and CSS properties anymore. Which limits your web design potential. Hence, Bootstrap 5 alpha decided to drop the support for IE 10 and 11.   Improved customizing docs There are some good improvisations in the documentation. Like, removing ambiguity,  giving more explanation, and providing much more support for extending Bootstrap. It all starts with a whole new Customize section. The color palette is expanded in v5, too. With an extensive color system built-in, you can more easily customize the look and feel of your app without leaving the codebase. There is an improvisation in color contrast, too. Also, they have provided color contrast metrics in Color docs. Hopefully, this will continue to help make Bootstrap-powered sites more accessible to folks all over.   The custom SVG icon library With Bootstrap 3, there were 250 reusable icon components in the font format called ‘Glyphicons”.  After that, with Bootstrap 4, it was scrapped. Because of that developers had to rely on free icon fonts or their SVG (Scalable Vector Graphic) icons to add value to their web designs. However, with Bootstrap 5 alpha, they introduced a brand new SVG icon library, which adds a fresh touch. These icons are brilliantly crafted by @Mark Otto, co-founder of Bootstrap, himself.   Adding CSS custom properties As mentioned, Bootstrap 5 alpha has begun using CSS custom properties thanks to dropping support for Internet Explorer. In v4 there were only a handful of root variables for color and fonts, and now developers have added them for a handful of components and layout options. For example table component, there are a handful of local variables to make striped, hoverable, and active table styles easier .table { --bs-table-bg: #{$table-bg}; --bs-table-accent-bg: transparent; --bs-table-striped-color: #{$table-striped-color}; --bs-table-striped-bg: #{$table-striped-bg}; --bs-table-active-color: #{$table-active-color}; --bs-table-active-bg: #{$table-active-bg}; --bs-table-hover-color: #{$table-hover-color}; --bs-table-hover-bg: #{$table-hover-bg}; // Styles here... }   Improved Utilities API  Well, this is by far the most interesting aspect of Bootstrap 5 alpha.  A brand new utility API. By using the utility API from Bootstrap you have unlimited possibilities to create utility classes for positioning, spacing, sizing, and so on. For example, you will be able to easily expand the number of `m-*`, `p-*` classes, and so on without writing custom Sass code to expand them. Here’s an example showing us how the $ utility variable can be expanded by adding multiple values: $utilities: () !default; $utilities: map-merge(   (     // ...     "width": (       property: width,       class: w,       values: (         25: 25%,         50: 50%,         75: 75%,         100: 100%,         auto: auto       )     ),     // ...     "margin": (       responsive: true,       property: margin,       class: m,       values: map-merge($spacers, (auto: auto))     ),     // ...   ), $utilities); We think this will be a game-changer for those who build on Bootstrap via source files, and if you haven’t built a Bootstrap-powered project that way yet, your mind will be blown.    Migrating the documentation from Jekyll to Hugo If you know how WordPress, Drupal, or Joomla works, then, you might be aware of how Jekyll works. Well, Jekyll is a free and open-source static site generator. Besides, it is useful to build websites with easy to use navigation, website components and generates all the content at once. However, Bootstrap 5 alpha is all set to step up its game and is switched to Hugo.  As it is a fast and flexible static site generator.   CONCLUSION One of the frustrating experiences of being a developer is reinventing the base HTML, CSS, and JavaScript for each project. While some prefer to write their code, it still makes sense to just use an existing framework like Bootstrap. With the all-new updates that came with Bootstrap 5 Alpha, We can surely say that the Bootstrap team is making very progressive steps to make the framework simple, lightweight, faster, useful, and more responsive for the developer’s benefit.   RELATED BLOGS: Easy jQuery Trick

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Jay Ukani

About the Author

Jay Ukani

3+ years of professional experience in Web design and Front-end technologies. I've worked across various platforms like HTML5, SCSS, LESS, CSS3, Bootstrap, Foundation, Javascript, Jquery, Wordpress, CMS Portal, ERP Portal, ERM Portal, and many more.

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