metaloha

Use a shortcode to define a drop-down form field, and shortcodes to define blocks of content that will be displayed when a specific entry is selected.
<h3>Usage</h3>
To add a content dropdown to a post, you can either select the Content Dropdown icon from the TinyMCE editor, or enter the shortcodes manually.
<pre><code>[dropdown name="controlName" class="customClassName"] - both `name` and `class` are optional; `name` will default to `dropdown-content`
</code></pre>
<ul>
<li>the <code>name</code> is used to identify which content sections are targetted by this dropdown; if there is only one dropdown on a page, it is optional; if there are multiple dropdowns on a page, each will need a unique name</li>
<li><code>class</code> can be a space-separated list of class names, or just a single class name</li>
<li>
only <code>[dropdown-option]</code> shortcodes may be inside this shortcode
[dropdown-option value=”someValue”] – the <code>value</code> field is technically optional, but is required if this option is meant to make a content block visible
</li>
<li>
must be inside a <code>[dropdown]</code> shortcode
[dropdown-content name=”controlName” value=”someValue”] – if the <code>name</code> matches a dropdown name, and the <code>value</code> matches the value of an option within that dropdown, then this content will be displayed when that specific option is selected.
</li>
<li>
again, <code>name</code> is technically optional, but must match a <code>[dropdown]</code> name (also defaults to <code>dropdown-content</code>)
</li>
<li><code>value</code> is required, and must match a <code>value</code> for a <code>[dropdown-option]</code></li>
<li>can be anywhere on the page</li>
</ul>
<h3>Example</h3>
Copy and paste the following content to see the plugin in action
[dropdown] 
[dropdown-option]Select one…[/dropdown-option] 
[dropdown-option value=”option1″]First option[/dropdown-option] 
[dropdown-option value=”option2″]Second Option[/dropdown-option] 
[/dropdown]
[dropdown-content value=”option1″]Content for the first option.[/dropdown-content]
[dropdown-content value=”option2″]Content for the second option.[/dropdown-content]
Those were all using the default values from the plugin. Let’s change it up a bit.
[dropdown] 
[dropdown-option value=”option1″]The First[/dropdown-option] 
[dropdown-option value=”option2″ default=true]The Second[/dropdown-option] 
[dropdown-option value=”option3″]The Third[/dropdown-option] 
[/dropdown]
You’ll notice below that the second option will be displayed by default for you.
[dropdown-content value=”option1″]Some different content for the second first option.[/dropdown-content]
[dropdown-content value=”option2″]Some different content for the second second option.[/dropdown-content]
[dropdown-content value=”option3″]Some different content for the second third option.[/dropdown-content]

Dropdown Content

Allows different content to be displayed based on the value of an author-defined drop-down box.

sevenspark

<a href="http://wpmegamenu.com/responsive-select-menu/" rel="nofollow ugc">View Demo 1</a>
<a href="http://agility.sevenspark.com/responsive-select-menu" rel="nofollow ugc">View Demo 2 in a Responsive WordPress Theme</a>
One common UI paradigm for navigation menus with responsive design is to display a select box (form element) 
for mobile devices. This plugin allows you to turn your WordPress 3 menu into a select box below a width of your choice.
<h4>Features</h4>
<ul>
<li>Takes up less screen real estate on mobile devices</li>
<li>Easier navigation for touch screens</li>
<li>Works automatically – no need to add extra PHP code</li>
</ul>
<h4>Highly Configurable</h4>
Through the Responsive Select Menu Control Panel you can:
<ul>
<li>New in 1.2 – select which theme locations to apply the menu to </li>
<li>Set your width breakpoint (where your menu switches from your standard menu to a select box)</li>
<li>Configure how many levels you wish to include in the select menu. Set it to 1 to include only the top-level menu items.</li>
<li>Choose the character used to indent your submenu items within the select box</li>
<li>Choose whether or not to exclude “dummy” items that don’t have links</li>
<li>Set the text of the first menu item</li>
</ul>
The demo is built with <a href="http://wpmegamenu.com/" rel="nofollow ugc">UberMenu – WordPress Mega Menu Plugin</a> , but it is designed to work with any UL-based WordPress 3 menu.
Based on the excellent tutorial from <a href="http://css-tricks.com/convert-menu-to-dropdown/" rel="nofollow ugc">Chris Coyier and CSS Tricks</a> – thanks!

Responsive Select Menu

The Responsive Select Menu plugin automatically turns any WordPress 3 Menu into a select box / dropdown on mobile devices.

Dropdown Content vs Responsive Select Menu