As the name suggests, this fork exists to allow support for <dialog> in IE8+. Bear in mind, IE8 is a very old browser, so some sacrifices needed to be made to get it to function properly.
dialog-polyfill-ie8.js aims to function as a drop-in replacement fordialog-polyfill.js. As with dialog-polyfill.js, it allows the usage of the <dialog> element in browsers not yet supporting it.
<dialog> is an element for a popup box in a web page, including a modal option which will make the rest of the page inert during use.
This could be useful to block a user's interaction until they give you a response, or to confirm an action.
See the HTML spec.
This package needs to have several libraries loaded before it will work in IE:
- html5-shiv - Allows HTML5 elements in IE8
- ie8 - Some browser specific DOM fixes for IE8
- dom4 - A cross-browser polyfill that aims for full DOM level 4 support in most major browsers
It is recommended that users install via NPM with the --only=production flag, as this library has a LOT of dev dependencies:
$ npm install dialog-polyfill-ie8 --only=production
This polyfill aims to work in modern versions of all major browsers, supporting IE8 and above.
- Include the CSS in the
<head>of your document, and the Javascript anywhere before referencingdialogPolyfill. - Create your dialog elements within the document. See limitations for more details.
- Register the elements using
dialogPolyfill.registerDialog(), passing it one node at a time. This polyfill won't replace native support. - Use your
<dialog>elements!
<head>
<link rel="stylesheet" type="text/css" href="/path/to/dialog-polyfill-ie8.css" />
</head>
<body>
<dialog>
I'm a dialog!
<form method="dialog">
<input type="submit" value="Close" />
</form>
</dialog>
<script src="/path/to/dialog-polyfill-ie8.js"></script>
<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.
When using the polyfill, the backdrop will be an adjacent element:
dialog::backdrop { /* native */
background-color: green;
}
dialog + .backdrop { /* polyfill */
background-color: green;
}You will need to edit the karma.conf.js
Once that is done, you can test by running:
grunt karma:dev
In the polyfill, modal dialogs have limitations-
- They should not be contained by parents that create a stacking context, see below
- The browser's chrome may not always be accessible via the tab key
- Changes to the CSS top/bottom values while open aren't retained
The major limitation of the polyfill is that dialogs should not have parents that create a stacking context.
The easiest way to solve this is to move your <dialog> element to be a child of <body>.
If this isn't possible you may still be able to use the dialog. However, you may want to resolve it for two major reasons-
- The polyfill can't guarantee that the dialog will be the top-most element of your page
- The dialog may be positioned incorrectly as they are positioned as part of the page layout where they are opened (defined by spec), and not at a fixed position in the user's browser.
To position a dialog in the center (regardless of user scroll position or stacking context), you can specify the following CSS-
dialog {
position: fixed;
top: 50%;
transform: translate(0, -50%);
}dialog.open may be a property, or a function, depending on the browser. Users intending to .
It is therefore recommended to use the dialog.openDialog method this library adds, which will consistently be implemented as a function across all browsers.