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

JavaScript DOM Scripting By Example Editing and Filtering Names Fix DOM Manipulation Code

javascript

help me solve this task such that the number you put in input field changes the font of the corresponding li element

app.js
const laws = document.getElementsByTagName('li');
const indexText = document.getElementById('boldIndex');
const button = document.getElementById('embolden');

button.addEventListener('click', (e) => {
    const index = parseInt(indexText.value, 10);

    for (let i = 0; i < laws.length; i += 1) {
       let law = laws[i];

       // replace 'false' with a correct test condition on the line below
       if (false) {

           law.style.fontWeight = 'bold';
       } else {
           law.style.fontWeight = 'normal';
       }
    }
});
index.html
<!DOCTYPE html>
<html>
<head>
  <title>Newton's Laws</title>
</head>
<body>
  <h1>Newton's Laws of Motion</h1>
  <ul>
    <li>An object in motion tends to stay in motion, unless acted on by an outside force.</li>
    <li>Acceleration is dependent on the forces acting upon an object and the mass of the object.</li>
    <li>For every action, there is an equal and opposite reaction.</li>
  </ul>
  <input type="text" id="boldIndex">
  <button id="embolden">Embolden</button>
  <script src="app.js"></script>
</body>
</html>

1 Answer

Jason Miller
seal-mask
.a{fill-rule:evenodd;}techdegree seal-36
Jason Miller
Full Stack JavaScript Techdegree Graduate 32,220 Points

Hey musab abdi,

This challenge is asking you to check if the value the user enters in the input const index = parseInt(indexText.value, 10); is an index in the HTML collection const laws = document.getElementsByTagName('li');. HTML collections are like arrays which means they are zero indexed. If the value the user enters is an index in the collection it will make the font-weight: bold; if not it will make the font-weight: normal.

so the answer is:

       if (index === i) {

           law.style.fontWeight = 'bold';
       } else {
           law.style.fontWeight = 'normal';
       }