jQuery没有处理由jQuery创建的元素

Question

I am dynamically adding list items to a list in jQuery through an ajax call that is called every second.

Below is the code for the ajax call.

$.ajax({
    url: 'php/update_group_list.php',
    data: '', 
    dataType: 'json',
    success: function(data) {
        var id = data.instructor_id;
            group_cnt = data.group_cnt,
            group_name = data.group_name,
            group_code = data.group_code;

            for (i = current_row; i < group_cnt; i++)
            {
                //setInterval(function() { $('#group-list-div').load('php/group_list.php'); }, 5000);

                $('#group-list').append("<li><a href='#' data-role='button' class='view-group-btns' id='"+group_code[i]+"' value='"+id+"' text='"+group_name[i]+"'>"+group_name[i]+"</a></li>");
                $('#delete-group-list').append("<fieldset data-role='controlgroup data-iconpos='right'>" +
                                                    "<input id='"+group_code[i]+i+"' value='"+group_code[i]+"' type='checkbox' name='groups[]'>" +
                                                    "<label for='"+group_code[i]+i+"'>"+group_name[i]+"</label>" +
                                                "</fieldset>");
            }

            current_row = i; 

            $('#group-list').listview('refresh');
            $('#delete-group-list').trigger('create');
    }
});

Now I am having two problems

FIRST PROBLEM:

When I try to run the code below (it should show an alert box if any of the list items created in this line $('#group-list').blah...blah in the code above), nothing happens.

$(".view-group-btns").click(function() 
{
    alert("check");
});

SECOND PROBLEM:

Also when I try to send the form data for the checkboxes (referencing line $('#delete-group-list').blah...blah in the ajax call code above) the post returns the error unexpected token <

What am I doing wrong? I think the two problems are related as I am creating the list items that are used dynamically.

---

Here is extra code relating to the SECOND problem

HTML:

<form id='delete-group-form' action='php/delete_groups.php' method='post'>
    <h3 style='text-align: center;'>Check the Box Beside the Groups you Would Like to Delete </h3>
    <div style='margin-top: 20px;'></div>
        <div id='delete-group-list'>
        </div>
    <div style='margin-top: 20px;'></div>
    <input type='submit' id='delete-groups-btn' data-theme='b' value='Delete Groups(s)'>                    
</form>

JS Code

$('#delete-group-form').submit(function(e) 
{
    e.preventDefault();

    alert($('#delete-group-form').serialize());

    if ($('#delete-group-form').serialize() == "") 
    {
        alert('No groups selected to be deleted.')
        return false;
    }
    else 
        if ($('#delete-groups-form').serialize() == null) 
        {
            alert('No groups selected to be deleted.')
            return false;
        } 
        else 
        {
            $.post('php/delete_groups.php',$('#delete-groups-form').serialize()).done(function(data) 
            {
                obj = jQuery.parseJSON(data);


                var group_codes = obj.group_list;

                alert(group_codes);

                alert("The selected groups have been deleted");
                window.setTimeout(2000);
                return false;
            });
        }
    return false;
});

delete_groups.php

<?php 
    $group_codes = $_POST['groups'];    
    $items = array('group_list'=>$group_codes); //creating an array of data to be sent back to js file
    echo json_encode($items); //sending data back through json encoding
?>

I think the root of the SECOND problem is the line $group_codes = $_POST['groups']; specfically the $_POST['groups'] because when I replace it with $group_codes = 'test'; (just for debugging purposes) , the code works as expected.

Answer 1

You need to use event delegation to make your newly-created elements function properly:

$("#group-list").on("click", ".view-group-btns", function() {
    alert("check");
});