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CSS jQuery Basics (2014) Creating a Mobile Drop Down Menu Using parent(), hasClass() and prop()

Ying Liang
Ying Liang
2,403 Points
Posted by Ying Liang
Ying Liang
2,403 Points

I am a little confused about .attr() and .prop(). What are the differences between them?

if($anchor.parent().hasClass("selected")){ $option.prop("selected",true);

}

I am not quite understand this code above. Why we need .parent()?

js/app.js 
//Problem: It look gross in smaller browser widths and small devices
//Solution: To hide the text links and swap them out with a more appropriate navigation

//Create a select and append to #menu
var $select = $("<select></select>");
$("#menu").append($select);

//Cycle over menu links
$("#menu a").each(function(){
  var $anchor = $(this);
  //Create an option
  var $option = $("<option></option>");

  //Deal with selected options depending on current page
  if($anchor.parent().hasClass(".selected")) {
    $option;
  }
  //option's value is the href
  $option.val($anchor.attr("href"));
  //option's text is the text of link
  $option.text($anchor.text());
  //append option to select
  $select.append($option);
});
//Create button 
var $button = $("<button>Go</button>");
$("#menu").append($button);
//Bind click to button
$button.click(function(){
  //Go to select's location
  window.location = $select.val();
});
index.html 
<!DOCTYPE html>
<html>
<head>
<link rel="stylesheet" href="css/style.css" type="text/css" media="screen" title="no title" charset="utf-8">
</head>
<body>
    <div id="menu">
        <ul>
            <li class="selected"><a href="index.html">Home</a></li>
            <li><a href="about.html">About</a></li>
            <li><a href="contact.html">Contact</a></li>
            <li><a href="support.html">Support</a></li>
            <li><a href="faqs.html">FAQs</a></li>
            <li><a href="events.html">Events</a></li>
        </ul>
    </div>
    <h1>Home</h1>
    <p>This is the home page.</p>
    <script src="//code.jquery.com/jquery-1.11.0.min.js" type="text/javascript" charset="utf-8"></script>
    <script src="js/app.js" type="text/javascript" charset="utf-8"></script>
</body>
</html>

1 Answer

David Royer
David Royer
10,026 Points
David Royer
David Royer
10,026 Points

Hi Ying,

For your two questions...

  1. I believe the primary difference for most cases is that the .prop() method allows us to get the value if it changes after a page loads. However, the .attr() method would NOT allow us to do this.

  2. You are selecting the parent because you need to work with the selected class, which is a class of the < li > element. The variable $anchor refers to the < a > elements. It's parents are the < li >'s, which is what we want to work with. Thus, we use $anchor.parent().

Hope that helps and let me know if you are still confused.

David