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JavaScript Interactive Web Pages with JavaScript Traversing and Manipulating the DOM with JavaScript Adding Multiple Event Listeners

Posted by Kyle Johnson
Kyle Johnson
8,499 Points

Multiple event listeners?

How do I add multiple event listeners? If I do just line 14, it says I need a second listener on "change". If I include line 15, it says I didn't use the method.

app.js 
//Select select box
var navigationSelect = document.getElementById("nav");

//Navigate to URL when select box is changed
var navigateToValue = function() {
  window.location = this.value;
}

//Send analytics data
var sendAnalytics = function() {
  //Placeholder  
}

navigationSelect.addEventListener("change", function(){navigateToValue;});
navigationSelect.addEventListener("change", function(){sendAnalytics;});
index.html 
<!DOCTYPE html>
<html>
  <body>
    <select id="nav">
      <option value="index.html">Home</option>
      <option value="about.html">About</option>
    </select>
    <h1>Home</h1>
    <script src="app.js"></script>
  </body>
</html>
about.html 
<!DOCTYPE html>
<html>
  <body>
    <select id="nav">
      <option value="index.html">Home</option>
      <option value="about.html">About</option>
    </select>
    <h1>About</h1>
    <script src="app.js"></script>
  </body>
</html>

1 Answer

Chyno Deluxe
Chyno Deluxe
16,936 Points

You are close but you have already declared your functions and therefore you do not need to create an annymous function to call on the other functions. Your code should look like this. View Below

//Select select box
var navigationSelect = document.getElementById("nav");

//Navigate to URL when select box is changed
var navigateToValue = function() {
  window.location = this.value;
}

//Send analytics data
var sendAnalytics = function() {
  //Placeholder  
}

navigationSelect.addEventListener("change", navigateToValue);
navigationSelect.addEventListener("change", sendAnalytics);

I hope this helps.