code: function show(elem, options) {
  		_prepareEvent()
  		var $elem = $(elem).first()	// only allow to show one dialog
  		if (!$elem.hasClass(CLS)) return false
  		// do nothing if this dialog is already shown
  		if (_.last(_stack) && _.last(_stack).elem === $elem[0]) return false
  		var dialog = new Dialog($elem, options)
  		dialog.show()
  	}
docs: api