Flickr

Using the Flirkr in 5 minutes rails screencast is was alble to include flikr into my website but I am at a loss for how to stop the user pressing tthe find button before they have put anything in the text box can anyone help?

code:

<%= form_remote_tag :url => {:action => 'search'}, :update => 'photos',    :complete => visual_effect(:blind_down, 'photos'),    :before => %(Element.show('spinner')),    :loaded => %(Element.hide('spinner')) %>

  <%= image_tag 'spinner.gif', :id => 'spinner', :style => 'display: none' %>   <fieldset id="images">     <label for='tags'>Enter search name:</label>     <%= text_field_tag 'tags' %>     <%= submit_tag 'Find' %>   </fieldset>   <div id="photos"></div> </form>