HookahJS
HookahJS is a tiny JavaScript library that monitors all input and textarea elements on your page and adds empty/dirty/touched
CSS hooks to each element automatically.
Introduction
HookahJS is a tiny JavaScript library that monitors all input and textarea elements on your page and adds the following CSS classes in response to user interactions with each element:
-
hkjs--empty
- control element is empty -
hkjs--not-empty
- control element is not empty -
hkjs--pristine
- control element has not seen aninput
orchange
event -
hkjs--dirty
- control element has seen aninput
orchange
event -
hkjs--untouched
- control element has not seen ablur
event -
hkjs--touched
- control element has seen ablur
event
HookahJS uses CSS @keyframes to detect new DOM elements so once the library is loaded, it will automatically add CSS hooks to new input and textarea elements. HookahJS is 1056 bytes (minified + gzipped).
Quickstart
To use HookahJS you only need to add hookah.js
to your page and the library will automatically add event listeners to all current and future input and textarea elements. The following example will draw a red box around an invalid input box after the user has touched the element:
<!doctype html>
<html>
<head>
<script src="//cdn.rawgit.com/muicss/hookahjs/0.0.6/dist/hookah.min.js"></script>
<style>
.hkjs--touched:not(:valid) {
border: 1px solid red;
}
</style>
</head>
<body>
<input type="text" required>
<input type="email" required>
</body>
</html>
HookahJS uses CSS @keyframes to detect new DOM elements so once the library is loaded, it will automatically add CSS hooks to new input and textarea elements.
Browser Support
- IE10+
- Opera 12+
- Safari 5+
- Chrome
- Firefox
- iOS 6+
- Android 4.4+
Note: HookahJS uses CSS @keyframes to detect new DOM elements automatically. To use HookahJS in IE9 you can initialize DOM elements explicitly with hkjs.init()
.
Documentation
How to load HookahJS
For production systems we recommend that you host the library file yourself which you can download from the dist/
directory in this repository:
For tighter integration with your code you can also use the HookahJS NPM package:
$ npm install --save hookahjs
var hkjs = require('hookahjs');
document.addEventListener('DOMContentLoaded', function() {
hkjs.init();
});
HookahJS can be loaded asynchronously but keep in mind that if HookahJS is initialized after the DOM content has been displayed to the user, there may be a flash of unstyled content. To avoid this you can seed your page with .hkjs--empty
/.hkjs--not-empty
classes as necessary.
How to initialize elements selectively
By default, HookahJS will add event listeners to all current and future input and textarea elements. To prevent this behavior you can listen to the hkjs-init
event and call the preventDefault()
method on the event object. You can also use the hkjs
global object to add hooks to individual elements:
window.addEventListener('hkjs-init', function(ev) {
// prevent HookahJS from adding hooks to all <input> and <textarea> elements
ev.preventDefault();
// use the `hkjs` global object to add hooks to elements manually
var inputEl = document.getElementById('my-input-element');
hkjs.init(inputEl);
});
How to handle programmatic updates
HookahJS can detect all change
and input
events triggered by user interactions but it can't detect programmatic changes to control elements. To update the HookahJS CSS classes after making a programmatic change to a control element, you can trigger a change
or input
event on the element:
// modify element
var inputEl = document.getElementById('my-input-element');
inputEl.value = 'Programmatic input';
// initialize event object (with bubbles = false)
var ev = document.createEvent('HTMLEvents');
ev.initEvent('change', false);
// trigger event
inputEl.dispatchEvent(ev);