Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

CSS jQuery Basics (2014) Creating a Mobile Drop Down Menu Using each()

Nick Davies
Nick Davies
7,972 Points
Posted by Nick Davies
Nick Davies
7,972 Points

Using Each - Challenge

I have been trying to work this out but no where before this video on the Front end developer track does it mention what an "anonymous function" is. I searched for what this meant but cannot find a solid answer.

Please can someone help me with what an anonymous function is?

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(){

};
  //Create an option
  //option's value is the href
  //option's text is the text of link
  //append option to select

//Create button 
//Bind click to button
  //Go to select's location
//Modify CSS to hide links on small width and show button and select
  //Also hides select and button on larger width and show's links
//Deal with selected options depending on current page
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>

2 Answers

moonshine
moonshine
8,449 Points
moonshine
moonshine
8,449 Points

An anonymous function is a function without a name. Example:

function() {

}
var timeout = setTimeout(function () {
    // The function inside the timeout is anonymous.
}, 1000);
Nick Davies
Nick Davies
7,972 Points
Nick Davies
Nick Davies
7,972 Points

Thank you that helps. Do you know why when being asked: "On line 9 of app.js, use the method we used to cycle over each of the menu links. Pass in an anonymous function too."

With my answer as: $("#menu a").each(function(){

};

Why is this wrong when the function is 'Anonymous'?

Thank you in advance Nick

moonshine
moonshine
8,449 Points

Did you forget the ")" before the ";"? 

$("#menu a").each(function () {
    // For each iteration do something in an anonymous function.
}); // "});" instead of "};"
Nick Davies
Nick Davies
7,972 Points
Nick Davies
Nick Davies
7,972 Points

So the reason why my code: $("#menu a").each(function(){

}; failed is because I didn't add a comment within it? because other than that and the spacing mine and yours are the same? $("#menu a").each(function () { // For each iteration do something in an anonymous function. });

Markus Ylisiurunen
Markus Ylisiurunen
15,034 Points
Markus Ylisiurunen
Markus Ylisiurunen
15,034 Points

Nick, it was because you didn't close the each() method.

$("#menu a").each(function () {

});

You have to add the last closing parenthesis after the function's closing bracket.

moonshine
moonshine
8,449 Points

I think you made a typo. The comment doesn't matter whatsoever. Like what Markus says.

Nick Davies
Nick Davies
7,972 Points
Nick Davies
Nick Davies
7,972 Points

I see now, Going to have to blame it on the long day!

Thank you both for your help, it is much appreciated!

Markus Ylisiurunen
Markus Ylisiurunen
15,034 Points
Markus Ylisiurunen
Markus Ylisiurunen
15,034 Points

Hi Nick!

Anonymous function is a function without a name. It's usually stored under a variable but can also be used in for example jQuery method handlers.

Here is an example of an anonymous function which is stored under a variable.

var uselessFunction = function() {
    // Put your code here
};

And here is an example of using anonymous function in a handler.

$('h1').each( function() {
    // Put your code here
});

// Or you can use the stored function instead
$('h1').each( uselessFunction );

Hope this helps you!