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JavaScript

Posted by brandonlind2
brandonlind2
7,823 Points

Does anyone know why my onclick event is returning null?

I'm trying to create drop down menu all in vanilla js and I cant figure out why the onclick function isnt working

<!DOCTYPE HTML>
<html>
 <head>
  <title>Store | Home</title>
  <meta charset="utf-8">
  <link rel="stylesheet" href="css/main.css">
  <link rel="stylesheet" href="css/main.css">
  <meta name="viewport" content="width=device-width" initial-scale="1.0">
 </head>
 <body>
  <header>
   <h1 class="main-header-title"> Store</h1>
   <nav>
    <ul>
     <li id="homeTab"><a href="index.html">Home</a></li>
     <li id="clothesTab"><a href="clothes.html">Clothes</a></li>
    </ul>
   </nav>
  </header>
  <section>
  </section>
  <footer>
   <ul>
     <li></li>
     <li></li>
     <li><a href="contact.html">Contact</a></li>
 </footer>
 <script src="https://code.jquery.com/jquery-1.12.0.min.js"></script>
 <script scr="js/main.js"></script>
 </body>
</html>

var header= document.getElementsByTagName('header')[0];
var nav=header.children[1].children[0];
var clothesTab= getId(clothesTab);

function getId(id){
            var element= document.getElementById(id);
            return element;
               }

function subUl(itemNum){                //creates unordered list that will be appended to the main one
            var subUl=document.createElement('ul');
                        for(i=0; i<itemNum; i++){
                var li=document.createElement('li');
                subUl.appendChild(li);
            }
            return subUl;
}
function displayDropMenu(navItem,num){

                    navItem.onclick=function(){navItem.appendChild(subUl(num));};
}           

displayDropMenu(clothesTab,2);
rydavim
rydavim
18,814 Points

Please post a workspace snapshot, or post the rest of your code, including html. That will make it much easier to trouble shoot and help you figure out what might be going wrong.

1 Answer

0yzh 󠀠
0yzh 󠀠
17,276 Points

document.getElementById is expecting a string so you could change your clothesTab variable to fix this problem:

var clothesTab = getId('clothesTab'); // <-- changed to a string

also, you probably already fixed it but your script tag has a typo ( "scr" instead of "src").