WordPress Theme Demo Bar is a plugin for wordpress that allows any wordpress theme to be previewed without activating it. A demo bar would be shown on top of page, allow users to preview another theme. The demo bar is customisable at admin panel. More than 1 extra CSS files can be loaded too.
Whats New in Version 1.6.1
<ul>
<li>Fixed error when use together with the new wordpress admin bar</li>
</ul>
Whats New in Version 1.3 to 1.5
<ul>
<li>Support child themes</li>
<li>With “Individual Theme Settings”, you can now display a link to theme info page and download/buy page at demo bar. <a href="http://zenverse.net/?themedemo=monoshade" rel="nofollow ugc">(Live in Action)</a></li>
<li>You can now display theme info, such as number of previews or preview URL using shortcode <code>[demobar]</code></li>
<li>To make the process easier, you can use media button to add it (see screenshot : Media Button)</li>
<li>You can do that in template files too, using the newly added template tag function <code>wptdb_output()</code></li>
<li>Now you can edit other theme’s options (functions.php) without activating it</li>
<li>Widget to show “Select Theme” drop-down menu (for your visitor to preview non-private themes)</li>
</ul>
Features
<ul>
<li>Preview any wordpress theme without activating it.</li>
<li>A demo bar will be shown on top of the page, allow users to preview another theme.</li>
<li>The demo bar can be deactivated.</li>
<li>You can hide your themes that are private.</li>
<li>You can load extra CSS files (more than one)</li>
<li>Demo Bar can be always on top now</li>
<li>You can cusmotise the look & feel of Demo Bar using CSS</li>
<li>Auto collection of popularity count (number of previews) of each theme.</li>
<li>Persistent preview, all internal links will be auto edited to keep the ?themedemo= variable.</li>
<li>Persistent preview can be turned off by the visitors by closing the demo bar (all links will then be reverted back automatically)</li>
<li>NEW Support child themes</li>
<li>NEW With “Individual Theme Settings”, you can now display a link to theme info page and download/buy page at demo bar</li>
<li>NEW You can now display theme info, such as number of previews or preview URL using shortcode <code>[demobar]</code></li>
<li>NEW To make the process easier, you can use media button to add it (see screenshot : Media Button)</li>
<li>NEW You can do that in template files too, using the newly added template tag function <code>wptdb_output()</code></li>
<li>NEW Now you can edit other theme’s options (functions.php) without activating it</li>
<li>NEW Widget available to show “Select Theme” drop-down menu (for your visitor to preview non-private themes)</li>
<li>NEW New template tag function <code>wptdb_list_themes()</code> to display drop-down menu</li>
</ul>
Usage
<ul>
<li>To preview any theme, simply add a variable “themedemo” to your site URL. For example: <code>myblog.com/?themedemo=the-theme-folder-name</code> <a href="http://zenverse.net/?themedemo=monoshade" rel="nofollow ugc">(Live in Action)</a></li>
<li>Alternatively, you can get the preview URL of all your themes at your Admin Panel > Settings > WP Theme Demo Bar</li>
<li>To hide the demo bar on individual theme, simply add a variable “hidebar” to your site URL. For example: <code>myblog.com/?themedemo=mytheme&hidebar=1</code> <a href="http://zenverse.net/?themedemo=monoshade&hidebar=1" rel="nofollow ugc">(Live in Action)</a></li>
<li>To load extra css, simply add a variable “extracss” to your site URL and seperate using comma. For example: <code>myblog.com/?themedemo=mytheme&extracss=blue,twocolumn</code> this loads blue.css and twocolumn.css from the theme’s directory</li>
</ul>
Documentations
<ul>
<li><a href="http://zenverse.net/using-shortcode-in-wordpress-theme-demo-bar-plugin/" rel="nofollow ugc">Understanding and Using Shortcode in WordPress Theme Demo Bar Plugin</a></li>
<li><a href="http://zenverse.net/using-template-tag-function-in-wordpress-theme-demo-bar-plugin/" rel="nofollow ugc">Using Template Tag Functions in WordPress Theme Demo Bar Plugin</a></li>
</ul>
Info & Links
<a href="http://zenverse.net/wordpress-theme-demo-bar-plugin/" rel="nofollow ugc">Plugin Info</a> | <a href="http://zenverse.net/" rel="nofollow ugc">Plugin Author</a>

WordPress Theme Demo Bar

Wordpress Theme Demo Bar allows any wordpress theme to be previewed without activating it. A demo bar would be shown on top of page, allow users to pr …

funlab

pingram

A CSS live Editor that allows you to preview realtime CSS changes and then save your changes. 
It saves dated backups of each save, so you can go back if it breaks, and you should erase backups once on a while. 
It’s a port from a Drupal module Live CSS http://drupal.org/project/live_css by guybedford http://drupal.org/user/746802 
Now using ACE editor http://ace.ajax.org/ 
Tested on WordPress 3.6. But needs more testing !
=capabilities.php problem (not bug) SOLVED !=
Ok, now I did the correct thing and created an action to the wp_loaded hook to init the plugin, then, 
check whether the user can “erase themes” which is an Admin capability only, so the plugin only works if you are an admin. 
No need to modify the capabilities.php nor anything else.
Some users have had problems in former 12.05 release with their site being inaccesible after installing the plugin. 
It all seemed to be part of the same problem with the capabilities.php file that is discussed here: 
https://wordpress.org/support/topic/fatal-error-call-to-undefined-function-wp_get_current_user-4?replies=32
It works nice and perfect for me, but still needs testing !!!
<h3>Hola mundo !</h3>
Este plugin está basado en el módulo de [Drupal Live CSS] (http://drupal.org/project/live_css) de [guybedford] (http://drupal.org/user/746802)
Es un editor de CSS que te permite editar en directo todas las hojas de estilo CSS de tu web, ver los cambios y guardar sobre la marcha. 
Está pensada para usarla al diseñar la web, por lo que conviene desactivarlo o desinstalarlo una vez terminada. Cada vez que se guardan los cambios se genera una copia de seguridad fechada, para que puedas volver atrás si hace falta. 
Utiliza ACE como editor.
Sólo los administradores pueden usar el plugin.
Importante !!!
Hacer copia de respaldo de los archivos CSS antes de probarlo ! 
Aunque el plugin genera automáticamente copias de seguridad fechadas en el mismo directorio en que estén los archivos modificados, siempre conviene tener una copia del estado general de la cosa antes de empezar a trastear. 
Si no funciona al guardar o hacer la copia de seguridad aparece un mensaje con las rutas del archivo que se intentaba modificar, la de la copia de seguridad y tal vez un mensaje de error. Lo más seguro es que el problema sea de permisos. Los CSS que quieras editar deberían tener permiso de escritura 755.
Instalación
La instalación es la típica de cualquier plugin de wordpress. Desempaquetar el zip en wp-content/plugins, y listo. No hay que tocar los temas ni hacer nada más que activarlo desde el panel de administración. 
No tiene opciones ni página propia en el panel de administración. 
Probado en WordPress 3.3.2, tienes que ser un administrador para poder usarlo.
Utiliza ahora el hook wp_loaded que arregla el problema de la versión anterior que se discutía aquí: https://wordpress.org/support/topic/fatal-error-call-to-undefined-function-wp_get_current_user-4?replies=32
Más información
<pre><code>http://drupal.org/project/live_css Live CSS
http://drupal.org/user/746802 guybedford
http://drupal.org/user/78427
http://mozillalabs.com/skywriter/2011/01/18/mozilla-skywriter-has-been-merged-into-ace/
http://www.ajax.org/
http://ace.ajax.org/

https://codex.wordpress.org/AJAX_in_Plugins
http://briancray.com/2009/08/19/wordpress-head-element/
http://www.devlounge.net/code/using-ajax-with-your-wordpress-plugin
http://amiworks.co.in/talk/simplified-ajax-for-wordpress-plugin-developers-using-jquery/

http://drupal.org/project/cssedit Realtime CSS Editor
http://drupal.org/user/78427 tjholowaychuk
</code></pre>

WP Live CSS Editor

Edit, preview changes in real time and save all your project's CSS stylesheets live in the browser.

WordPress Theme Demo Bar vs WP Live CSS Editor