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JavaScript JavaScript and the DOM (Retiring) Traversing the DOM Sibling Traversal

Posted by Zak Mosbacher
.a{fill-rule:evenodd;}techdegree seal-36
Zak Mosbacher
Full Stack JavaScript Techdegree Graduate 16,080 Points

Im not sure what im doing wrong here,

i think im getting confused with all the different parents and siblings.

app.js 
const list = document.getElementsByTagName('ul')[0];

list.addEventListener('click', function(e) {
  if (e.target.tagName == 'BUTTON') {
    let p = e.target.parentNode;
    let nextP = p.nextElementSibling;
    let parent = list.parentNode;
    if (nextP) {
    parent.insertBefore(nextP , p);
    }
  }
});
index.html 
<!DOCTYPE html>
<html>
    <head>
        <title>JavaScript and the DOM</title>
    </head>
    <link rel="stylesheet" href="style.css" />
    <body>
        <section>
            <h1>Making a Webpage Interactive</h1>
            <p>Things to Learn</p>
            <ul>
                <li><p>Element Selection</p><button>Highlight</button></li>
                <li><p>Events</p><button>Highlight</button></li>
                <li><p>Event Listening</p><button>Highlight</button></li>
                <li><p>DOM Traversal</p><button>Highlight</button></li>
            </ul>
        </section>
        <script src="app.js"></script>
    </body>
</html>

1 Answer

Antonio De Rose
Antonio De Rose
20,885 Points
Antonio De Rose
Antonio De Rose
20,885 Points 
const list = document.getElementsByTagName('ul')[0];

list.addEventListener('click', function(e) {
  if (e.target.tagName == 'BUTTON') {
    let p = e.target.parentNode; //this will return <li><p><DOM Traversal</p><button>Highlight></li>
    let nextP = p.nextElementSibling; // this will return <section> all of inside >/section
    let parent = list.parentNode; //this will do nothing, as it does not know what is list
    if (nextP) {
    parent.insertBefore(nextP , p); // ending up this will do nothing too.
    }
  }
});

//got an easier solution

const list = document.getElementsByTagName('ul')[0];

list.addEventListener('click', function(e) {
  if (e.target.tagName == 'BUTTON') {
        let p = e.target.previousSibling; //this will return the corresponding <p>DOM Traversal</p> for the button click
        p.className = 'highlight'; // now that you have entire node / element, it is a matter of adding the class
  }
});

//and if you like to chain your method
//you could even write it in one statement

e.target.previousSibling.className = 'highlight';
Zak Mosbacher
.a{fill-rule:evenodd;}techdegree seal-36
Zak Mosbacher
Full Stack JavaScript Techdegree Graduate 16,080 Points

Thank you! I think i just got confused on how to target the paragraph element with previousSibling