== stencil ==

By default, <code>tabindex</code> is set to <code>-1</code>:

--input--
    <div class="text-right">
        <%= dropdown
             ['Dropdown 1', id => 'a_custom_id', right, items => [
                ['Item 1', ['item1'] ],
                ['Item 2', ['item2'] ],
                [],
                ['Item 3', ['item3'] ]
             ] ] %>
    </div>
--end input--
--output--
    <div class="text-right">
        <div class="dropdown">
            <button class="btn btn-default dropdown-toggle" type="button" id="a_custom_id" data-toggle="dropdown">Dropdown 1</button>
            <ul class="dropdown-menu dropdown-menu-right">
                <li><a class="menuitem" href="item1" tabindex="-1">Item 1</a></li>
                <li><a class="menuitem" href="item2" tabindex="-1">Item 2</a></li>
                <li class="divider"></li>
                <li><a class="menuitem" href="item3" tabindex="-1">Item 3</a></li>
            </ul>
        </div>
    </div>
--end output--


== stencil ==
...but it can be overridden:
--input--
    <%= dropdown
         ['Dropdown 2', caret, large, primary, items => [
            ['Item 1', ['item1'], data => { attr => 2 } ],
            ['Item 2', ['item2'], disabled, data => { attr => 4 } ],
            [],
            ['Item 3', ['item3'], data => { attr => 7 } ],
            [],
            ['Item 4', ['item4'], tabindex => 4 ],
            'This is a header',
            ['Item 5', ['item5'] ],
         ] ] %>
--end input--
--output--
    <div class="dropdown">
        <button class="btn btn-lg btn-primary dropdown-toggle" type="button" data-toggle="dropdown">Dropdown 2 <span class="caret"></span></button>
        <ul class="dropdown-menu">
            <li><a class="menuitem" href="item1" tabindex="-1" data-attr="2">Item 1</a></li>
            <li class="disabled"><a class="menuitem" href="item2" tabindex="-1" data-attr="4">Item 2</a></li>
            <li class="divider"></li>
            <li><a class="menuitem" href="item3" tabindex="-1" data-attr="7">Item 3</a></li>
            <li class="divider"></li>
            <li><a class="menuitem" href="item4" tabindex="4">Item 4</a></li>
            <li class="dropdown-header">This is a header</li>
            <li><a class="menuitem" href="item5" tabindex="-1">Item 5</a></li>
        </ul>
    </div>
--end output--