dialog-polyfill.js is a polyfill for <dialog>.
<dialog> is an element for a popup box in a web page. See
more information and demos
and the
HTML spec.
You may optionally install via Bower-
$ bower install dialog-polyfill
This polyfill works on modern versions of all major browsers. It also supports IE9 and above.
<head>
<script src="dialog-polyfill.js"></script>
<link rel="stylesheet" type="text/css" href="dialog-polyfill.css" />
</head>
<body>
<dialog>I'm a dialog!</dialog>
<script>
var dialog = document.querySelector('dialog');
dialogPolyfill.registerDialog(dialog);
// Now dialog acts like a native <dialog>.
dialog.showModal();
</script>
</body>In native <dialog>, the backdrop is a pseudo-element:
#mydialog::backdrop {
background-color: green;
}When using the polyfill, the backdrop will be an adjacent element:
#mydialog + .backdrop,
#mydialog::backdrop {
background-color: green;
}- Modailty isn't bulletproof. For example,
accessKeycan be used to focus inert elements.- While focus is inside a
<dialog>, the browser's chrome cannot be tabbed to.
- While focus is inside a
- The polyfill
<dialog>should always be a child of<body>. - Polyfill top layer stacking can be ruined by playing with z-index.
- The polyfill
<dialog>does not retain dynamically set CSS top/bottom values upon close. - Anchored positioning is not implemented. The native
<dialog>in Chrome doesn't have it either.