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JavaScript JavaScript Loops, Arrays and Objects Tracking Multiple Items with Arrays Build a Quiz Challenge, Part 2 Solution

Marcio Mello
Marcio Mello
7,861 Points
Posted by Marcio Mello
Marcio Mello
7,861 Points

Need assistance with my code.

Hello everyone!

After watching the solution, I went back and tried to improve my previous solution. I decided to create a function that target the specific "node" in the DOM where the new HTML created should be placed.

He is how it looks like:

function print(node, message) {
  var outputNode = document.getElementById(node);
  outputNode.innerHTML = message;
}

It very similar to the Challenge Solution presented, but I decided to go with two parameter so it could be used on a bigger project.

However, when I try to run the project, I get the following error: ˜Cannot change innerHTML of null˜.

He is How I am trying to print it:

html += "<h2>You have got " + correctAnswers.length +  " out of 3 correct answers!</h2>";
document.write(html);

html = "<h3>Correct Answers</h3>";
html += createHtmlList(correctAnswers);
print("correctList", html);

html = "<h3>Wrong Answers</h3>";
html += createHtmlList(wrongAnswers);
print("wrongList", html);

The "correctList" and "wrongList"refers to the HTML

<div id="correctList">

</div>
<div id="wrongList">

</div>

I also added CSS to differentiate both list:

#correctList {
  color: blue;
}

#wrongList {
  color: red;
}

Can I get some help?

PS: If anyone wonder what the createHTMLList func is:

function createHtmlList( list ) {
    var htmlSnipet = "<ol>"
    for ( i = 0; i < list.length; i++ ) {
    htmlSnipet += "<li>" + list[i] + "</li>";
    }
    htmlSnipet += "</ol>";
    return htmlSnipet;
  }

my list of variables is:

var answer;
var correctAnswers = [];
var wrongAnswers = [];
var html;

var questions = [
  ["How many paws a dog has?", "4"],
  ["What is the name of our planet?", "earth"],
  ["Who is de president of the United States?", "obama"]
];

1 Answer

Gabriel D. Celery
Gabriel D. Celery
13,810 Points
Gabriel D. Celery
Gabriel D. Celery
13,810 Points

Where is your script tag loading the JS file compared to this?

<div id="correctList">

</div>
<div id="wrongList">

</div>

Make sure the divs are placed before the script so that they exist when the script is loaded.