'use strict'; var clickHandlers = { 'go': function _go() { var URL = document.getElementById('URL').value; var a = new MozActivity({ name: 'view', data: {type: 'url', url: URL }}); a.onsuccess = function() { alert('Success!'); }; a.onerror = function() { alert('Failure going to URL'); }; } }; document.body.addEventListener('click', function(evt) { if (clickHandlers[evt.target.id || evt.target.dataset.fn]) clickHandlers[evt.target.id || evt.target.dataset.fn].call(this, evt); });