Double loading issue in Javascript / jQuery/Microsoft-ajax hybrid

Question

Hey StackOverflow.

I Have an odd issue with some JavaScript code (again, I hate debugging JS code). I am working on a regular table - which I fill up from a JSON call, and have added in support for some paging (sort of 2x paging I guess you could call it), sorting and some selecting of rows. Everything is working nicely - BUT when a row is DESELECTED (and deselected only) my add_navigate event gets fired twice, which results in a bit of reloading of data that is not needed - and an indication of loading that is even more not needed.

First here's my JS code:

var customerType;
var selYear;
var selMonth;
var sdir;
var sort;
var page;
var noteId;
var hasDoneCall;
var customerId;

var customerIdChanged = false;


function initValues() {
    customerType = "Publisher";
    selYear = new Date().getFullYear();
    selMonth = new Date().getMonth()+1;
    sdir = false;
    sort = "CustomerName";
    page = 1;
    noteId = false;
    customerId = 0;

    hasDoneCall = location.href.indexOf('#') > 0;

}
function flash(elm, color, duration) {

    var current = elm.css('backgroundColor');

    elm.animate({ backgroundColor: 'rgb(' + color + ')' }, duration / 2).animate({ backgroundColor: current }, duration / 2);

}

function createNotes(elm) {
    var btn = jQuery(elm);
    btn.attr('disabled', 'disabled');
    bulkCreditOption('true', '', function(changeSet) {
        var i = 0;
        while (i < changeSet.length) {
            var selector = "input[type=checkbox][value=" + changeSet[i] + "].check:checked";
            var row = jQuery(selector).parent().parent();
            var cell = row.find("td:nth-child(2)");

            cell.html("<a href=\"javascript:showNotes('" + changeSet[i] + "')\">" + cell.html() + "</a>");
            flash(row, '60, 130, 200', 500);
            i++;
        }
        btn.removeAttr('disabled');
    });
}

function deleteNotes(elm) {
    var btn = jQuery(elm);
    btn.attr('disabled', 'disabled');
    bulkCreditOption('', 'true', function(changeSet) {
        var i = 0;
        while (i < changeSet.length) {
            var selector = "input[type=checkbox][value=" + changeSet[i] + "].check:checked";
            var row = jQuery(selector).parent().parent();
            var cell = row.find("td:nth-child(2)");

            cell.html(cell.text());
            flash(row, '60, 130, 200', 500);
            i++;
        }
        btn.removeAttr('disabled');
    });
}

function bulkCreditOption(createNotes, deleteNotes, callback) {
    var path = "/BulkCredit";
    var data = "";
    var checked = jQuery("input[type=checkbox].check:checked");
    checked.each(function(chk) {
        data += "&ids=" + urlencode(jQuery(this).val());

    });
    jQuery.ajax({
        type: 'POST',
        url: path,
        dataType: 'json',
        data: "createNotes=" + urlencode(createNotes) + data + "&deleteNotes=" + urlencode(deleteNotes),
        success: function(msg) {
            callback(msg);
        }
    });
}

initValues();

Sys.Application.add_init(function() {
    Sys.Application.add_navigate(function(sender, e) {
        var reinstate = e.get_state();
        if (typeof (reinstate) != 'undefined' && typeof (reinstate.customerType) != 'undefined') {
            customerType = reinstate.customerType;
            selYear = reinstate.selYear;
            selMonth = reinstate.selMonth;
            sdir = reinstate.sdir;
            sort = reinstate.sort;
            page = reinstate.page;
            noteId = reinstate.noteId;
            customerId = reinstate.customerId;

        } else {
            initValues();
        }

        if (!customerIdChanged) {

            jQuery("#customerTypeChanger").val(customerType);

            jQuery("#customerFilter").val(customerId);

            jQuery("#monthPicker").empty();

            makeMonthPicker();

            if (noteId != false && noteId != 'false') {
                doShowNotes();
            } else {
                jQuery("#notesContent").hide();
                jQuery("#tableContent").show();
                doAjaxCall();
            }
        } else {
            //logic to fetch customer specific stuff here, TODO
            customerIdChanged = false;
        }
    });
    Sys.Application.set_enableHistory(true);


    jQuery(document).ready(function() {
        origColor = jQuery("#dataTable > thead > tr > th").css('backgroundColor');

        makeMonthPicker();

        jQuery("#customerTypeChanger").val(customerType);
        jQuery("#customerTypeChanger").change(function() {
            customerType = jQuery(this).val();
            iqSetHistory();
        });

        jQuery("#customerFilter").change(function() {
            customerId = jQuery(this).val();
            var tableBody = jQuery("#dataTable > tbody");
            tableBody.find("tr").removeClass("selected");
            tableBody.find("tr[rel=" + customerId + "]").addClass("selected");
            customerIdChanged = true;
            iqSetHistory();
        });

        jQuery(".checkAll").click(function() {
            var elm = jQuery(this);
            if (elm.is(':checked')) {
                jQuery(".check").attr('checked', 'checked');
            } else {
                jQuery(".check").removeAttr('checked');
            }
        });

        if (!hasDoneCall) {
            if (noteId == false) {
                doAjaxCall();
            } else {
                doShowNotes();
            }
        }

    });
});

function makeMonthPicker() {
    var selDate = new Date();
    selDate.setFullYear(selYear);
    selDate.setMonth(selMonth-1);
    jQuery("#monthPicker").monthPicker(function(year, month) {
        selYear = year;
        selMonth = month;
        iqSetHistory();
    }, selDate);
}

var origColor;
var notesPath = "/ShowNotes";


function fadeOut(elm) {
    elm.animate({ backgroundColor: 'rgb(180, 180, 180)' }, 250);
}
function fadeIn(elm) {
    elm.animate({ backgroundColor: origColor }, 250);
}

function iqSetHistory() {
    var state = { 'customerType': customerType, 'selYear': selYear, 'selMonth': selMonth, 'sdir': sdir, 'sort': sort, 'page': page, 'noteId': noteId, 'customerId':customerId };

    Sys.Application.addHistoryPoint(state);
}
var ajaxPath = "/GetCreditListMonth";
function doAjaxCall() {

    fadeOut(jQuery("#dataTable > thead > tr > th"));
    jQuery.ajax({
        type: "POST",
        url: ajaxPath,
        dataType: "json",
        data: "month=" + selMonth + "&year=" + selYear + "&custType=" + customerType + "&sort=" + sort + "&sdir=" + sdir + "&page=" + page + "&asCsv=false",
        success: function(msg) {
            var table = jQuery("#dataTable");

            var tableBody = table.find("tbody");


            tableBody.empty();

            var i = 0;
            while (i < msg.Rows.length) {
                var data = msg.Rows[i];
                var row = jQuery("<tr rel=\"" + data.CustomerId + "\"></tr>");

                if (data.CustomerId == customerId) {
                    row.addClass("selected");
                }

                if (i % 2 == 1) {
                    row.addClass("alternatetablerow");
                }

                var custName = data.CustomerName;
                if (data.PaymentCreated) {
                    custName = "<a href=\"javascript:showNotes('" + getCreditId(data.CustomerId) + "')\">" + custName + "</a>";
                }
                row.append("<td><input type=\"checkbox\" class=\"check\" name=\"ids\" value=\"" + getCreditId(data.CustomerId) + "\" /></td>");
                row.append("<td>" + custName + "</td>");
                row.append("<td>" + data.AmountExcludingTaxes + "</td>");
                row.append("<td>" + data.BonusAmount + "</td>");
                row.append("<td>" + data.Amount + "</td>");

                row.appendTo(tableBody);
                i++;
            }


            tableBody.find("input, a").click(function(event){ //Stop clicks from falling through to the table row event
                event.stopPropagation();
                return true;
            });
            tableBody.find("tr").click(function(event){
                var row = jQuery(this);
                if (row.hasClass("selected")) { //Deselect
                    jQuery("#customerFilter").val(0);
                } else {
                    jQuery("#customerFilter").val(jQuery(this).attr('rel'));
                }
                jQuery("#customerFilter").triggerHandler("change");
            });



            createPager(msg.Pages, jQuery("#pager"));
            jQuery(".checkAll").triggerHandler('click');

            fadeIn(table.find('thead > tr > th'));
        }
    });
}

function downloadListAsCsv() {
    window.location.href = ajaxPath + "?month=" + selMonth + "&year=" + selYear + "&custType=" + customerType + "&sort=" + sort + "&sdir=" + sdir + "&page=0&asCsv=true";
}

function doShowNotes(){
    jQuery.ajax({
        type: "GET",
        url: notesPath + "/" + noteId,
        success: function(msg) {
            jQuery("#tableContent").hide();
            jQuery("#notesContent").html(msg).show();

        }

    });
}

function showNotes(id) {
    noteId = id;
    iqSetHistory();
}

function showTable() {
    noteId = false;
    iqSetHistory();
}

function getCreditId(custId) {
    return selYear + "-" + selMonth + "-" + custId;
}

function sortDataTable(col) {
    if (col == sort) {
        sdir = !sdir;
    } else {
        sdir = false;
    }

    page = 1

    sort = col;
    iqSetHistory();
}

function createPager(totalPages, elm) {
    elm.empty();
    if (totalPages > 1)
        {
            var builder = "";


            var numDirections = 2;

            if (page > 1)
            {
                if (page - numDirections - 1 > 0)
                {
                    builder += CreatePageLinkStatic(1, "&laquo;");
                    builder += " ";
                }

                builder += CreatePageLinkStatic(page - 1, "&lt;");
                builder += " ";
            }

            var n = page - numDirections;
            while (n < page)
            {
                if (n > 0)
                {
                    builder += CreatePageLinkStatic(n, n);
                    builder += " ";
                }
                n++;
            }

            builder += page;
            builder += " ";

            n = page + 1;

            while (n <= page + numDirections && n <= totalPages)
            {
                builder += CreatePageLinkStatic(n, n);
                builder +=" ";
                n++;
            }

            if (page < totalPages)
            {
                builder += CreatePageLinkStatic(page + 1, "&gt;");
                builder += " ";
                if (page + numDirections < totalPages)
                {
                    builder += CreatePageLinkStatic(totalPages, "&raquo;");
                }
            }

            builder;

            elm.append(builder);
        }

}
function CreatePageLinkStatic(page, str){
    return "<a href=\"javascript:pageDataTable(" + page + ")\">" + str + "</a>";
}

function pageDataTable(newPage){
    page = newPage;
    iqSetHistory();
}

And the markup:

<div id="tableContent">
<select id="customerTypeChanger">
    <option selected="selected" value="Publisher">Publisher</option>
    <option value="Advertiser">Advertiser</option>
</select>
<select id="customerFilter"><option value="0">Choose Customer</option><option value="1">Customer 1</option><option value="1">Customer 2</option>...</select>
<div id="monthPicker"></div>
<div><a href="javascript:downloadListAsCsv()">DownloadAsCSV</a></div>
    <table id="dataTable" class="grid">
        <thead>
            <tr>
                <th style="text-align: left"><input type="checkbox" name="toggleCheckBox" class="checkAll" value="dummy" /></th>
                <th><a href="javascript:sortDataTable('CustomerName')">Customer name</a></th>
                <th><a href="javascript:sortDataTable('AmountExcludingTaxes')">Amount</th>
                <th><a href="javascript:sortDataTable('BonusAmount')">Bonus amount</a></th>
                <th><a href="javascript:sortDataTable('Amount')">Amount including VAT</a></th>
            </tr>
        </thead>
        <tbody></tbody>
    </table>
    <div class="pagination" id="pager"></div>
    <div>With the selected rows</div>
<input id="createNotes" type="button" value="Create notes" onclick="javascript:createNotes(this)" /> <input id="deleteNotes" value="Delete notes" type="submit" onclick="javascript:deleteNotes(this)" />

</div>
<div id="notesContent"></div>

If needed as well, here's the code I did for the monthpicker (it is a very basic datepicker thing that just lets you flick back and forth between months and gives an output like

< April 2009 May 2009 June 2009 >

(where bold is clickable links taking you to see just that month period, and italic is the already selected one, obviously actual html markup differs)

It utilizes the datepicker from jQuery UI to get the localized names of the months

(function($) {


    var selDate;

    $.fn.monthPicker = function(callback, selectedDate) {

        selDate = selectedDate;

        var elm = this;

        this.html("<span class=\"prevMonthButton\"><a href=\"\">&lt;</a></span><span class=\"prevMonth\"><a href=\"\"></a></span><span class=\"curMonth\"></span><span class=\"nextMonth\"><a href=\"\"></a></span><span class=\"nextMonthButton\"><a href=\"\">&gt;</a></span>");

        populateDates(this);

        var prevMonthFunc = function() {

            var month = selDate.getMonth() - 1;
            if (month < 0) {
                month = 11;
                selDate.setFullYear(selDate.getFullYear() - 1);
            }
            selDate.setMonth(month);

            populateDates(elm);
            callback(selDate.getFullYear(), selDate.getMonth() + 1);
            return false;
        }
        var nextMonthFunc = function() {
            var month = selDate.getMonth() + 1;
            if (month > 11) {
                month = 0;
                selDate.setFullYear(selDate.getFullYear() + 1);
            }
            selDate.setMonth(month);

            populateDates(elm);
            callback(selDate.getFullYear(), selDate.getMonth() + 1);
            return false;
        };

        this.find(".prevMonth > a").click(prevMonthFunc);
        this.find(".prevMonthButton > a").click(prevMonthFunc);
        this.find(".nextMonth > a").click(nextMonthFunc);
        this.find(".nextMonthButton > a").click(nextMonthFunc);
    }

    function populateDates(elm) {

        var months = jQuery.datepicker._defaults.monthNames;
        var selYear = selDate.getFullYear();
        var selMonth = selDate.getMonth();


        elm.find(".curMonth").text(months[selMonth] + " " + selYear);

        var prevMonth = selMonth - 1;
        var prevYear = selYear;
        if (prevMonth < 0) {
            prevMonth = 11;
            prevYear = prevYear - 1;
        }

        elm.find(".prevMonth > a").text(months[prevMonth] + " " + prevYear);

        var nextMonth = selMonth + 1;
        var nextYear = selYear;
        if (nextMonth > 11) {
            nextMonth = 0;
            nextYear = nextYear + 1;
        }

        elm.find(".nextMonth > a").text(months[nextMonth] + " " + nextYear);
    }
})(jQuery);

I know most of this JavaScript code sucks - but for the main part it seems to do the job quite nicely, but as I said click a row to select it, then click it to deselect and boom, double call to add_navigate which results in an extra call to my JSON service and a visual flicker on the client side - and I cannot work out why it happens (and even more strange, why it just happens when it is deselected and not on a selected one as well).

Answer 1

I would try doing

.unbind('click').click(function()

instead of

.click(function()

Just to make sure click events are not getting bound twice.

Answer 2

Oh Sorry I had completely forgotten about this question.

I restructured some of my code a little while after this and the issue was then gone. I am not exactly sure what caused this, seeing as it still surprised me how I only ever, seemingly, got the double loading half the time.

Anyhoow, the issue is solved, only I don't know how or why, which still slightly bothers me, but on the other hand - it works.

Answer 3

I think the issue is with double binding of events to the same element unconsiously.

This is usually the scenario,

(function($){
   var MyDocument = new Object({
       prepareBody : function(){

          //addClick Event
          $('div#updatedElement').click(MyDocument.ajaxCall());

          //adjusting the height of an updatedElement to an-otherElement
          $('div#updatedElement').css('height', $('div#otherElement').height());
       },
       ajaxCall : function(){

          //do your ajax Call
           $.getJSON('index.php',{param:1, param:2},function(response){

                //do something with your response
                $('div#updatedElement').html(response)

               //say if after your call you decide to update the body again
                MyDocument.prepareBody();

               //what that does is you will double bind click to the updateElement div.
               //The next time that it is click, the AjaxCall function will run twice
                //The next time it is clicked the MyDocument.ajaxCall function will be run four times

                //8 - 16 - 32 and by now, firefox would have crashed!

           },'json');
       }
   });
   $(document).ready(function(){
       MyDocument.prepareBody()
   });
})(jQuery);

So as advised by KClough, unbind Events before binding them so that they run only once! Sad jQuery does not overwrite them as do other frameworks!

Hope this helps some one else