Auto Check Radio Box if it is the only one being displayed

Question

So, I have radio boxes of the form

<li><input type="radio" name="names" value="blah"><a>Some text (blah)</a></li>

There are 100 plus of these radio buttons.

Now, I have a jQuery filter, from here. The filter works well.

But, I want to set a jQuery statement that will auto select the radio button if it is, amongst the shown, the only one remaining.

The filter uses show() and hide(), which I presume means it switches it from display: block to display: none;

My best crack at doing this on my own looks like this, but it's not working:

     if($('li').attr({"display":"block"}).size()==1)
      {
      $('input[cvs_name]:eq(1)').attr('checked', 'checked');
      }

How can I do this?

Answer 1

var $visible = $('ul').find('li:visible');
if($visible.length == 1) {
    $visible.find('input:radio').attr('checked','checked');
}

Answer 2

Try this:

if ($("li:visible").length === 1) {
    $("li:visible input").attr("checked", "checked");
}

jQuery has a visible filter which only selects elements which aren't hidden. (And, of course, a hidden filter which selects those which are.)