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A prototype/lowpro based Facebook-style windowing solution



PopupJS is a simple Prototype-based library for creating Facebook-like popup windows and dialogs. It leverages Dan Webb's excellent Low Pro library to allow you to unobtrusively create popup windows with a minimal amount of code.

popup window

Dependencies: prototype.js, dragdrop.js, effects.js, lowpro.js

Learn More:

Copyright (c) 2008-2011, John W. Long
Portions copyright (c) 2008, Five Points Solutions, Inc.


PopupJS depends on Prototype, Scriptaculous, and Low Pro. To use PopupJS you will need to download and install them in the appropriate directory on your web server and reference them with script tags in the head portion of your HTML document:

<script type="text/javascript" src="/javascripts/prototype.js"></script>
<script type="text/javascript" src="/javascripts/effects.js"></script>
<script type="text/javascript" src="/javascripts/dragdrop.js"></script> 
<script type="text/javascript" src="/javascripts/lowpro.js"></script>

After including all of the dependencies in your HTML document, don't forget to include PopupJS:

<script type="text/javascript" src="/javascripts/popup.js"></script>

There are also a number of images included in the distribution. You should install these in your "images" folder on your web server.

PopupJS expects you to style the contents of your popup windows yourself. The contents of a popup window includes the titlebar, buttons, etc. If you are looking for some basic styles to get you started, check out "facebook.css" in the distribution.

Low Pro Behaviors

PopupJS makes heavy use a custom Low Pro behavior that makes it easy to unobtrusively attach the popup functionality to the DOM.

If you are not familiar with Low Pro and unobtrusive javascript, check out this article on Dan Webb's blog:

Using the Trigger Behavior

The Popup.Trigger behavior allows you to open up any div or URL inside of a Facebook-style window. To use it you must install the behavior using Low Pro's friendly addBehavior function:

  'a.popup': Popup.TriggerBehavior()

The code above associates all links with a class of "popup" with the Popup.TriggerBehavior. This allows you to create a popup link like this:

<a class="popup" href="window.html">Popup</a>

The link above will use Ajax to open the contents of "window.html" in a Facebook-like popup window. Note that the contents of "window.html" will be inserted directly into the DOM. Don't include the normal HTML head and body tags in the window document, just include the snippet of HTML that should be inserted.

If you would like to store the contents of your windows on the same page, place it in a hidden div:

<div id="hello" class="popup" style="hidden">Hello World</div>

In your popup link, set the href attribute of the link to the ID of the div like this:

<a class="popup" href="#hello">Popup</a>

The link above would open the contents of the "hello" div in a popup window when clicked.

Manually Creating Popup Windows

The trigger behavior is useful for the simple case where you want to associate a link with a popup window, but sometimes you need more control.

In these cases you can manually create a popup window in code, like this:

var popup = new Popup.Window('element_id', {draggable: true});;

The Popup.Window constructor accepts two parameters. The first is the ID of the element that contains the contents of the popup window. The second is the options hash. For regular popup windows, there is only one option: draggable. By default, this option is false, but when set to true it allows a window to be repositioned by dragging the titlebar. The titlebar element must have a class of "popup_title" (this can be configured with the Popup.TitlebarClass variable).

If you need to create an Ajax window, you can use the following code:

var popup = new Popup.AjaxWindow(url, {reload: false});;

The Popup.AjaxWindow constructor accepts two parameters. The first is the URL of the contents of the popup window, and the second is an options hash. The options hash can contain the draggable and reload options. The reload option is true by default and controls whether or not the contents of the window will be reloaded each time the window is shown.

To hide a window, use the hide function:


Popup Dialogs

PopupJS also includes replacements for the standard alert and confirm javascript functions so that you can easily display message boxes and confirmation dialogs.

Here's a couple of examples:

// OK alert dialog
Popup.alert('Hello World!');

// Confirmation dialog with OK and Cancel buttons
Popup.confirm('Are you sure?', {
  okay: function() { ... },
  cancel: function() { ... }

If you want more control over the buttons used in the dialog, you can use the Popup.dialog() function:

// Completely custom dialog with Yes, No, and Maybe
  title: 'Friend Request',
  message: 'Add Dwight Schrute as a friend?',
  buttons: ['Yes', 'No', 'Maybe'],
  buttonClick: function(button) { ... }

The Popup.alert() and Popup.confirm() functions are implemented in terms of the Popup.dialog() function and both accept the same options as the Popup.dialog() function. To use a custom title and buttons on an alert dialog you could do this:

Popup.alert('Jim was here.', {title: 'The Office', buttons: ['Yup'] });

Support and Contributions

All of the development of PopupJS takes place on GitHub:

If you run into a problem, please file a ticket on the issue tracker. Or even better, submit a pull request. Contributions are welcome and encouraged.


PopupJS is distributed under an MIT-style license. Use it for good or for awesome.

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