DOM Animations

Learn how to create HTML animations with JavaScript.

A Basic Web Page

To illustrate how to create HTML animations with JavaScript, we will use a basic web page example:

Example

<!DOCTYPE html>
<html>
<body>

<h1>My First JavaScript Animation</h1>

<div id=”animation”>My animation will go here</div>

</body>
</html>

Create an Animation Container

All animations should be anchored to a container element.

Example

<div id =”container”>
<div id =”animate”>My animation will go here</div>
</div>

Style the Elements

The container element should be set with style=”position: relative“.

The animated element should be set with style=”position: absolute“.

Example

#container {
width: 400px;
height: 400px;
position: relative;
background: yellow;
}
#animate {
width: 50px;
height: 50px;
position: absolute;
background: red;
}

Animation Code

JavaScript animations are created by programming gradual changes in an element’s style.

These changes are triggered by a timer. When the timer interval is short, the animation appears smooth and continuous.

The basic code is:

Example

id = setInterval(frame, 5);

function frame() {
  if (/* test for finished */) {
    clearInterval(id);
  } else {
    /* code to change the element style */
  }
}

Create the Full Animation Using JavaScript

Example