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

Mikhailo Rozumovskyy
Mikhailo Rozumovskyy
3,779 Points
Posted by Mikhailo Rozumovskyy
Mikhailo Rozumovskyy
3,779 Points

I cannot find solution for this problem, plzz

Here is the description of the problem and my code is attached bellow. What i am doing wrong?

A delegated click event listener has been attached to the selected ul element, which is stored in the variable list. The handler is targeting each button in the list. When any one of the buttons is clicked, a class of highlight should be added to the paragraph element immediately preceding that button inside the parent list item element. Add the code to create this behavior on line 5.

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

list.addEventListener('click', function(e) {
  if (e.target.tagName == 'BUTTON') {
    let p = e.target.parentNode;
    let li = p.parentNode;
    p.className = 'highlight';
  }
});
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

Stuart Wright
Stuart Wright
41,118 Points
Stuart Wright
Stuart Wright
41,118 Points

I've added my comments to the three lines of code that you've written. Hopefully these will help you arrive at the correct solution:

    let p = e.target.parentNode;  // This is where you've gone wrong. You should be looking for the element that is the previous sibling of the button element, not the parent.
    let li = p.parentNode;  // This line is unnecessary, you can delete it, as you never do anything with your new variable.
    p.className = 'highlight';  // This line is correct.
Mikhailo Rozumovskyy
Mikhailo Rozumovskyy
3,779 Points
Mikhailo Rozumovskyy
Mikhailo Rozumovskyy
3,779 Points

I am sooo thankful to you. I did it with your help. I should have more practice and confidence with DOM!