This page lists some common setups for the popup calendar. ... For each example it's structured like this: there's the <form> that contains the input field, and following there is the JavaScript snippet that setups that form. ... Basic setup: one input per calendar. ... Input field with a trigger button. ... The calendar now puts the date into 2 elements: one is an input field of type "hidden" so that the user can't directly see or modify it and one is a <span> element in which the date is displayed. ...