Detection if an element is added to DOM

domcheck.js

// Detection if an element is added to DOM
function onElementInserted(containerSelector, elementSelector, callback) {
    var onMutationsObserved = function(mutations) {
        mutations.forEach(function(mutation) {
            if (mutation.addedNodes.length) {
                var elements = $(mutation.addedNodes).find(elementSelector);
                for (var i = 0, len = elements.length; i < len; i++) {
                    callback(elements[i]);
                }
            }
        });
    };

    var target = $(containerSelector)[0];
    var config = { childList: true, subtree: true };
    var MutationObserver = window.MutationObserver || window.WebKitMutationObserver;
    var observer = new MutationObserver(onMutationsObserved);
    observer.observe(target, config);
};

// Usage
onElementInserted('containerSelector', '.elementSelector', function(e){
    alert('Element added to the DOM');
});