Joomla Request Confirmation Before Closing

jconfirm.js

/*
 * This goes at the top of your plugin edit view,
 * and will ask for confirmation before you leave.
 * Be sure to replace viewname with your controller
 * name, shortened. If you follow 2.5 guidelines
 * with sub controllers that handel specific parts
 * of the application, then this will work fine.
 */

Joomla.submitbutton = function(task) {
	var confirmation = true;
	var viewname = <?php echo JRequest::get('view'); ?>;
	if(task ===  viewname + '.cancel')
	{
		var confirmation = confirm('Have changes to save? Click Cancel, and then Save. Otherwise, click ok.');
	}
	if(confirmation)
	{
		if (task == viewname + '.cancel' || document.formvalidator.isValid(document.id(viewname + '-form'))) {
			Joomla.submitform(task, document.getElementById(viewname + '-form'));
		}
		else {
			alert('<?php echo $this->escape(JText::_('JGLOBAL_VALIDATION_FORM_FAILED'));?>');
		}
	}
};