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Writing a boolean expression to solve

While working through the application process for a bootcamp, I was tasked with the following JS problem which is above my head. I was successful in testing through the JS console on Chrome but when I attempt to plug the code into the .js file, it does not work. Do I need to apply a boolean expression? If so, what is the best way of coding it?

Here is everything that is in the .js file:

      document.addEventListener("DOMContentLoaded", function(event) {
      var thumbnailElement =  document.getElementById("smart_thumbnail");
      thumbnailElement.addEventListener("click", function() {
      // write here                                                                                                                                                                                             
      });
      });

Here is the problem that is at hand:

"To make the image bigger or smaller, you have to change its class. In your JavaScript console, run this code:

      var thumbnailElement = document.getElementById("smart_thumbnail"); 
      thumbnailElement.className; This displays what the class currently is; it 
      should be 
      "small", unless you changed it since.'

To make it big, you should remove the class, by running this:

       thumbnailElement.className = ""; To make it small again, you can put it back:

       thumbnailElement.className = "small";'

See how it changes from small to big? You should put the line that makes it big in your JavaScript file so that it executes when the user clicks."

about 4 years ago · Juan Pablo Isaza
2 answers
Answer question

0

You could use the HTMLElement.classList.toggle method to add or remove the class. Here is a small snippet that illustrates how you can do it.

<style>
  .small {
    transform: scale(0.5);
  }
</style>

<button class="small" id="smart_thumbnail">Click me</button>

<script>
  document.addEventListener("DOMContentLoaded", function (event) {
     
// Get the element by id
    var thumbnailElement = document.getElementById("smart_thumbnail"); 

    // add the event listener on the element
    thumbnailElement.addEventListener("click", function () {
      thumbnailElement.classList.toggle("small");
      /*
        
      HTMLElement.classList.toggle(className) will remove the class if it is in the class list OR add it if it is not already there.

    */
    });
  });
</script>

If you simply want to remove it, you can use the remove method instead.

thumbnailElement.classList.remove("small");
about 4 years ago · Juan Pablo Isaza Report

0

if you have the css of the elment in the id and changing its size by class then it will not work here is the code that I wrote to solve

        <!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Answer</title>
    <style>
        .small{
            width: 10%;
            height: 10%;
            transition: all 1s ease;
        }
        
        .notSmall{
            width: 30%;
            height: 30%;
            transition: all 1s ease;
        }
    </style>
</head>
<body>
    <img src="Your Image" class="small" id="smart_thumbnail" alt="The image">
    <script>
    document.addEventListener("DOMContentLoaded", () => {
      let thumbnailElement =  document.getElementById("smart_thumbnail");
      thumbnailElement.addEventListener("click", function() {
        if(thumbnailElement.classList == "small"){
            thumbnailElement.classList.remove('small');
            thumbnailElement.classList.add('notSmall');
            console.log('now image is big')
        }else{
            thumbnailElement.classList.add('small');
            thumbnailElement.classList.remove('notSmall');
            console.log('now image is small')
        }
      });
      });
    </script>
</body>
</html>
about 4 years ago · Juan Pablo Isaza Report
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