jQuery File Upload not working when file input dynamically created

Question

i am using this jquery uploader (http://blueimp.github.io/jQuery-File-Upload/basic.html) and it works fine when the file input is put in the raw code of the site, however i am dynamically appending the fields with jquery and it doesnt work. here is the jquery to trigger the upload:

$('.fileupload').fileupload({
    dataType: 'json',
    done: function (e, data) {
        $.each(data.result.files, function (index, file) {
            alert(file.name);
            //$('<p/>').text(file.name).appendTo(document.body);
        });
    }
});

and this is what SHOULD trigger the upload:

<input class="fileupload" type="file" name="files[]" data-url="uploads/">

Here is the code that is appended by jquery:

$(document).on('click','.addItem', function(){
            $('<!--ROW START-->\
                <form class="widget-content item" data-url="uploads/">\
                    <div class="row">\
                        <div class="col-md-3"><input type="text" class="form-control" name="itemName[]"></div>\
                        <div class="col-md-3"><textarea class="auto form-control" name="itemDescription[]" cols="20" rows="1" style="word-wrap: break-word; resize: vertical;"></textarea></div>\
                        <div class="col-md-3"><textarea class="auto form-control" name="itemCondition[]" cols="20" rows="1" style="word-wrap: break-word; resize: vertical;"></textarea></div>\
                        <input type="hidden" class="itemId" name="itemId[]" value="">\
                        <input type="hidden" name="itemInventoryId[]" value="<?=$_GET["inventory_id"]?>">\
                        <input type="hidden" name="itemParent[]" value="'+$(this).closest('.formHolder').data('parent-room')+'">\
                        <div class="col-md-2">\
                            <div class="fileinput-holder input-group">\
                                <input class="fileupload" type="file" name="files[]">\
                            </div>\
                        </div>\
                        <div class="col-md-1 align-center"><i class="save icon-ok large"> </i>&nbsp;&nbsp;&nbsp;<i class="delete icon-trash large"> </i></div>\
                    </div>\
                </form>\
            <!--/ROW END-->').fadeIn(500).appendTo($(this).parents().siblings('.items'));
            $(this).parent().parent().siblings('.widget-header, .header-margin, .hide').removeClass('hide').fadeIn();
        });

like i say, when i add it into the actual code, not dynamically its fine. Can someone help please?

Answer 1

This is because you bind fileupload event before element is added.

Try moving your code into callback function which will be executed after you create input element. Since appendTo() doesn't support callback, you can use each(callback):

$('code_that_you_append').appendTo('some_element').each(function () {
    // here goes $('.fileupload').fileupload({ ... }) function
});

If you need to bind event to .fileupload in multiple places in code, you can create a function to avoid code repetition, like this:

function bindFileUpload() {
    $('.fileupload').fileupload({
        dataType: 'json',
        done: function (e, data) {
            $.each(data.result.files, function (index, file) {
                alert(file.name);
            });
        }
    });
};

and then call it in the callback, like before:

$('code_that_you_append').appendTo('some_element').each(function () {
    bindFileUpload();
});

I've created a little demo. It binds click instead of fileupload to simplify things (fileupload is external plugin...), but the general rule stays the same.