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

Barbara Szczygielska
Barbara Szczygielska
7,535 Points
Posted by Barbara Szczygielska
Barbara Szczygielska
7,535 Points

Not clear challenge description

I feel totally misguided by the challenge description. What am I supposed to do here? Add heighligth class to which paragraph? I'm not native english speaker maybe that's a problem though I believe this description is tangled a bit.

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

list.addEventListener('click', function(e) {
  if (e.target.tagName == 'BUTTON') {

  }
});
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>

2 Answers

Tsenko Aleksiev
Tsenko Aleksiev
3,819 Points
Tsenko Aleksiev
Tsenko Aleksiev
3,819 Points

Ok, so you are asked to grab the paragraph before each button ( check the index.html, does are the paragraphs )

<li><p>Element Selection</p><button>Highlight</button></li> //Element Selection
<li><p>Events</p><button>Highlight</button></li> //Events
<li><p>Event Listening</p><button>Highlight</button></li> //Event Listening
<li><p>DOM Traversal</p><button>Highlight</button></li> //DOM Traversal

and add the highlight class to it. So, you must grab the target of the function, aka the button, use a property to get the target's previous sibling and set it's class to "highlight". Get it? You need only this on line 5:

e.target.previousSibling.className = "highlight";

and that's it :)

Tsenko Aleksiev
Tsenko Aleksiev
3,819 Points
Tsenko Aleksiev
Tsenko Aleksiev
3,819 Points

No problem, I'm glad I helped :)