Your calling this from hook_menu, correct? I don't believe that suffix can be used from here. At least it's not in the list of valid return values in listed on the hook_menu page.
You'll need to add the suffix to whatever the output of your url is, if it's a form, it can nicely be added to the form via the form api.
Example:
Let's say your function manager_checkins_history_page
is a form that uses the form aip, and looks something like this:
function manager_checkins_history_page($form, &$form_state){
$form['switch'] = array(
'#type' => 'checkbox',
'#title' => t('i'm a chekcbox'),
'#default_value' => false,
);
$form['submit'] = array(
'#type' => 'submit',
'#value' => t('Submit'),
);
return $form;
}
if you wanted to apply a suffix to the whole form, you could do something like:
function manager_checkins_history_page($form, &$form_state){
$form['group1'] = array(
'#type' => 'fieldset',
'#title' => t('Your Name'),
'#suffix' => "I'm a suffix for your form",
);
$form['group1']['switch'] = array(
'#type' => 'checkbox',
'#title' => t('i'm a chekcbox'),
'#default_value' => false,
);
$form['group1']['submit'] = array(
'#type' => 'submit',
'#value' => t('Submit'),
);
return $form;
}
That would give you a form, wrapped in a box, with a suffix at the end.