Filtering Simple Search HTML

I want to add a 'placeholder' attribute to the search input field (without using javascript), but I cannot seem to get this filter, located in custom.php, to take:

Filtering Omeka's Simple Search function to display default message
Uses HTML5 'placeholder' attribute
Browser support will vary
function my_simple_search($html,$buttonText = "Search", $formProperties=array('id'=>'simple-search'), $uri = null)
    // Always post the 'items/browse' page by default (though can be overridden).
    if (!$uri) {
        $uri = uri('items/browse');

    $searchQuery = array_key_exists('search', $_GET) ? $_GET['search'] : '';
    $formProperties['action'] = $uri;
    $formProperties['method'] = 'get';
    $html  = '<form ' . _tag_attributes($formProperties) . '>' . "\n";
    $html .= '<fieldset>' . "\n\n";
    $html .= __v()->formText('search', $searchQuery, array('name'=>'textinput','class'=>'textinput','placeholder'=>'Login to Search Items'));
    $html .= __v()->formSubmit('submit_search', $buttonText);
    $html .= '</fieldset>' . "\n\n";

    // add hidden fields for the get parameters passed in uri
    $parsedUri = parse_url($uri);
    if (array_key_exists('query', $parsedUri)) {
        parse_str($parsedUri['query'], $getParams);
        foreach($getParams as $getParamName => $getParamValue) {
            $html .= __v()->formHidden($getParamName, $getParamValue);

    $html .= '</form>';
    return $html;

I also tried removing all but the $html vars, but I think the issue is that the filter is just not registering at all for some reason.

What's missing here?

Thanks -- E

The problem here is that there is no "simple_search" filter.

Since your filter function is already written to completely replicate and replace the simple_search code with your modified version, it will probably be easiest for you to just replace your theme's call to simple_search with one to your custom my_simple_search function. That wouldn't require any filters at all.

Oh right. Duh. Thanks.