I’ve copied the code for a product filtering system from the W3 schools website (includes JavaScript, CSS and html) but it’s not working as intended. I’m doing this for a school project and the code is working perfectly fine for my classmates who also copied it straight from the W3 schools website. I showed my teacher my code and they couldn’t see the issue. There are 6 buttons, including a “show all” option which can be used to filter through a range of products. This is what it looks like when the products page is first opened (hasn’t been interacted with yet):
The “Show all” option is selected by default (shown by the grey colour)
However, when I try selecting another button, the previous button selected doesn’t revert to the colour white, instead it stays grey:
This eventually results in all the buttons turning grey (in this example I haven’t selected the two rightmost buttons). This makes it difficult to tell which filter is currently selected.
I know it’s a very minor detail, but I would greatly appreciate any help because my project is due very soon (:
As I said, all my code was copied directly from the W3 schools website, and I have checked many times that the code is identical, however the problem persists. I will paste and screenshot the CSS and JavaScript code because I don’t think the problem is in the HTML, but if you think the problem could be in my html code, then I can show you that as well. Another option is that the issue could be to do with my ‘over-arching’ CSS code which is used to style both the home and products pages, so I can include that if you’d like it.
This is the JavaScript code:
filterSelection("all") // Execute the function and show all columns
function filterSelection(c) {
var x, i;
x = document.getElementsByClassName("column");
if (c == "all") c = "";
// Add the "show" class (display:block) to the filtered elements, and remove the "show" class from the elements that are not selected
for (i = 0; i < x.length; i++) {
w3RemoveClass(x[i], "show");
if (x[i].className.indexOf(c) > -1) w3AddClass(x[i], "show");
}
}
// Show filtered elements
function w3AddClass(element, name) {
var i, arr1, arr2;
arr1 = element.className.split(" ");
arr2 = name.split(" ");
for (i = 0; i < arr2.length; i++) {
if (arr1.indexOf(arr2[i]) == -1) {
element.className += " " + arr2[i];
}
}
}
// Hide elements that are not selected
function w3RemoveClass(element, name) {
var i, arr1, arr2;
arr1 = element.className.split(" ");
arr2 = name.split(" ");
for (i = 0; i < arr2.length; i++) {
while (arr1.indexOf(arr2[i]) > -1) {
arr1.splice(arr1.indexOf(arr2[i]), 1);
}
}
element.className = arr1.join(" ");
}
// Add active class to the current button (highlight it)
var btnContainer = document.getElementById("myBtnContainer");
var btns = btnContainer.getElementsByClassName("btn");
for (var i = 0; i < btns.length; i++) {
btns[i].addEventListener("click", function(){
var current = document.getElementsByClassName("active");
current[0].className = current[0].className.replace(" active", "");
this.className += " active";
});
}
If a screenshot is easier to read:
This is the CSS code (for the entire products page, not just the button filters):
products {
margin-bottom: 100px;
/* Center website */
.main {
max-width: 1000px;
margin: auto;
}
h1 {
font-size: 50px;
word-break: break-all;
align-items: center;
text-align: center;
justify-content: center;
}
.row {
margin: 8px -16px;
}
/* Add padding BETWEEN each column (if you want) */
.row,
.row > .column {
padding: 8px;
}
/* Create three equal columns that floats next to each other */
.column {
float: left;
width: 33.33%;
display: none; /* Hide columns by default */
}
/* Clear floats after rows */
.row:after {
content: "";
display: table;
clear: both;
}
/* Content */
.content {
background-color: white;
padding: 10px;
}
/* The "show" class is added to the filtered elements */
.show {
display: block;
}
/* Style the buttons */
.btn {
border: none;
outline: none;
padding: 12px 16px;
background-color: white;
cursor: pointer;
}
/* Add a grey background color on mouse-over */
.btn:hover {
background-color: #ddd;
}
/* Add a dark background color to the active button */
.btn.active {
background-color: #666;
color: white;
}
}
Screenshot of the CSS:
