Add onClick event on form input with multiple checkbox

To add a javascript onclick event on a form input with multiple checkbox, use this alternative method:

$options = array(); 
foreach($roles as $value => $label) { 
  $options[] = array( 
    'name' => $label, 
    'value' => $value, 
    'onClick' => 'showDiv(this)' 
  ); 
} 
echo $form->input('Role', array('options' => $options, ...)); 

But why use inline javascript? You could do this with one line of mootools:

$('input[id^=ModelRole][type=checkbox]').addEvent('click', showDiv);
(replace 'Model' with the name of your model)

And I’m sure it’s just as easy (or easier) in jQuery or other frameworks.