jQuery addClass example

Change class name on click in jQuery

by aparadise

HTML

<div id="banner-message">
  <p>Hello World</p>
  <button>Change color</button>
</div>

CSS

body {
  background: #20262E;
  padding: 20px;
  font-family: Helvetica;
}

#banner-message {
  background: #fff;
  border-radius: 4px;
  padding: 20px;
  font-size: 25px;
  text-align: center;
  transition: all 0.2s;
  margin: 0 auto;
  width: 300px;
}

button {
  background: #0084ff;
  border: none;
  border-radius: 5px;
  padding: 8px 14px;
  font-size: 15px;
  color: #fff;
}

#banner-message.alt {
  background: #0084ff;
  color: #fff;
  margin-top: 40px;
  width: 200px;
}

#banner-message.alt button {
  background: #fff;
  color: #000;
}

JavaScript

// find elements

var button = $("button")
//https://www.youtube.com/watch?v=_lEgIImHoM4
 //ternary :? operator
 
 $("#banner-message").val() != '' ? $(button).show() : $(button).hide();
 
 
//ternary short hand for if else start like this
// 1. ():? : ;
//. (true test statement)

//example
var x = 1; //true but if i chagne to zero its false
(true == x) ? alert(' x is true number = ' + x) : alert('this is false if it zero or less');