jQuery Uploadify: Show Start Upload button when file is selected

hello all,

http://www.aspsnippets.com/Articles/Upload-files-with-Progress-Bar-in-ASPNet-using-jQuery.aspx from this reference 

how to hide start and cancel button before select any image in uploadify pulgins?

<a style="display:none" class="btn btn-success btn-sm" id="a1" href="javascript:$('#<%=FileUpload1.ClientID%>').fileUploadStart()">Start Upload</a>&nbsp;
                                <a style="display:none" class="btn btn-danger btn-sm"  id="a2" href="javascript:$('#<%=FileUpload1.ClientID%>').fileUploadClearQueue()">Clear</a>
                               <div style="padding:40px">
                                   <asp:FileUpload ID="FileUpload1" runat="server" />
  <script type="text/javascript">
         $(window).load(       
        
    function () {
        $("#<%=FileUpload1.ClientID %>").fileUpload({
            'uploader': 'js/uploader.swf',
            'cancelImg': 'images/cancel.png',
            'buttonText': 'Browse Files',
            'script': 'Handler.ashx',
            //'folder': 'uploads',
            'fileDesc': 'Image Files',
            'fileExt': '*.jpg;*.jpeg;*.gif;*.png',
            'scriptData': { "Product_Id": "<%= pid.Text %>" },
            // 'scriptData': { "Product_Id": '11111' },
            'multi': true,
            'auto': false,
            'sizeLimit': 1048576,
            'onError': function (a, b, c, d) {
                if (d.status == 404)
                    alert("Could not find upload script. Use a path relative to: " + "<?= getcwd() ?>");
                else if (d.type === "HTTP")
                    alert("error " + d.type + ": " + d.status);
                else if (d.type === "File Size")
                    alert(c.name + " " + d.type + " Limit: " + Math.round(d.info / (1024 * 1024)) + "MB");
                else
                    alert("error " + d.type + ": " + d.text);
            },
            'onAllComplete': function (event, queueID, fileObj, response, data) {
                var btn = document.getElementById('<%= this.btnbindimage.ClientID %>').click();
            }
        });
}