javascript - jQuery .on() method doesn't see new elements

Question

I'm getting a JSON element and building a list from its items like this:

getTitles: function(data) {
    data = data || {};
    var list = [];

    $.getJSON(
        '/titles',
        data,
        function(data) {
            $.each(data.data, function(key, val) {
                list.push(
                    '<li><a href="'+ val.href +'">'+ val.title +'</a><span class="count">'+ val.count +'</span></li>'
                )
            });

            $('#title-items').html(list.join(''));
        }
    );
}

And I'm binding click event for a elements like this:

$('a').on('click', function(e) {
    alert('clicked');
    e.preventDefault();
});

Old a elements shows alert but new ones follow URL. Event handler doesn't work for new ones. How can I solve this?

Answer 1

You are not using the correct code to get live functionality.

$('#title-items').on('click', 'a', function(e) {
    alert('clicked');
    e.preventDefault();
});

1. First, select your common ancestor element (#title-items in this example). You can use document here too if you want to handle all a elements.
2. Pass the event type (on), then the sub selector (a), and then the callback function for the event.

Now, when click events bubble up to #title-items, it will check to see if the element is an a element, and if so, fire the callback.