How TO - Filter Elements
Learn how to filter a DIV element based on it's class name.
Filter DIV Elements
BMW
Orange
Volvo
Red
Mustang
Blue
Cat
Dog
Melon
Kiwi
Banana
Lemon
Cow
Create Filterable DIV Elements
Step 1) Add HTML:
Example
<!-- Control buttons -->
<div id="myBtnContainer">
<button
class="btn active" onclick="filterSelection('all')"> Show all</button>
<button class="btn" onclick="filterSelection('cars')"> Cars</button>
<button class="btn" onclick="filterSelection('animals')"> Animals</button>
<button class="btn" onclick="filterSelection('fruits')"> Fruits</button>
<button class="btn" onclick="filterSelection('colors')"> Colors</button>
</div>
<!-- The filterable elements. Note that
some have multiple class names (this can be used if they belong to multiple
categories) -->
<div
class="container">
<div
class="filterDiv cars">BMW</div>
<div class="filterDiv colors
fruits">Orange</div>
<div class="filterDiv cars">Volvo</div>
<div class="filterDiv colors">Red</div>
<div class="filterDiv cars
animals">Mustang</div>
<div class="filterDiv colors">Blue</div>
<div class="filterDiv animals">Cat</div>
<div class="filterDiv
animals">Dog</div>
<div class="filterDiv fruits">Melon</div>
<div class="filterDiv fruits animals">Kiwi</div>
<div class="filterDiv
fruits">Banana</div>
<div class="filterDiv fruits">Lemon</div>
<div class="filterDiv animals">Cow</div>
</div>
Step 2) Add CSS:
Example
.container {
overflow: hidden;
}
.filterDiv {
float: left;
background-color: #2196F3;
color: #ffffff;
width: 100px;
line-height: 100px;
text-align: center;
margin: 2px;
display: none; /* Hidden by default */
}
/* 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:
#f1f1f1;
cursor: pointer;
}
/* Add a light grey
background on mouse-over */
.btn:hover {
background-color: #ddd;
}
/* Add a dark background to
the active button */
.btn.active {
background-color: #666;
color: white;
}
Step 3) Add JavaScript:
Example
filterSelection("all")
function filterSelection(c) {
var x, i;
x = document.getElementsByClassName("filterDiv");
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 control 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";
});
}
Try it Yourself »
