Jquery Mobile val() returns undefined after changePage - jquery-mobile

Question

I have 2 pages that I'm working with: first being the page where the values are being fetched from php server and populating the selects/inputs and the second page being a dialog box that fetches the value from the hidden inputs in the first page. The first transition opens the dialog box and fetches the values properly. After which I save the values in php session and reload the first page. After this process when I open the dialog box again the jquery is not able to fetch val() and shows undefined. I'm not sure if this is due to some reloading of the page issue or something else. If I refresh the page then it will work fine again.
<div data-role="page" id="page1">
<div data-theme="a" data-role="header">
.....
<div data-role="navbar" data-iconpos="top">
.....
</div>
<div data-theme="c" id="cashtab" data-role="content">
<div style="display:none" id="proddata" data=""></div>
<div style="display:none" id="prodstock" data=""></div>
<form id="mainsubmit" action="form.php" method="post" data-ajax="false">
<input id="formproduct" type="hidden" name="product" value=""/>
<div id="productsearch" style="width:48%; float:left; margin-right:2%;">
<label for="search">Search Product:</label><br/><br/>
<ul id="productautocomplete" data-role="listview" data-inset="true" data-filter="true" data-filter-placeholder="Select a product... (type at least 3 letters)" data-filter-theme="d"></ul>
</div>
<div id="packingselect" style=" width:23%; float:left; margin-right:2%;">
<label for="packing">Select Packing:</label>
<select name="packing" id="packing" data-iconpos="left">
</select>
</div>
<div id="qtyenter" style=" width:23%; float:left; margin-right:2%;">
<label for="quantity">Select Qty:</label>
<input type="number" data-clear-btn="true" name="quantity" id="qty" value=""/>
</div><br/><br/><br/><br/><br/><br/><br/><br/>
<div style="display:inline-block; width:33%; margin-left:33%; margin-right:33%;">
<a href="#page3" data-rel="dialog" data-role="button" >ADD</a>
</div>
</form>
</div>
</div>
<div data-role="page" id="page3" data-url="dialog.html" data-close-btn="right">
<div data-role="header">
<h1>Batch Selection</h1>
</div>
<div data-role="content">
<div style="overflow:auto;">
<table id="batchsel" style="border:1px;">
<thead>
<tr>
<th></th>
<th>Batch No</th>
<th>Exp Date</th>
<th>Brate</th>
<th>Srate</th>
<th>Packing</th>
<th>Stock</th>
<th>Supplier</th>
<th>ST%</th>
<th>Bill Date</th>
<th>Bill No</th>
<th>btax</th>
</tr>
</thead>
<!--data populated from server once the values from first page is read properly.
<!-- currently not loading the second time as unable to fetch val() -- >
<tbody>
</tbody>
</table>
</div>
<div id="remainingdata">
<p1 id="changeable_requirements"></p1>
<!-- function the send the checked checkboxes relavent info to store in session -->
<button id="saveprod" onclick="addProduct(); return false;">Add Product</button>
</div>
</div>
</div>
<script>
$( document ).on( "pageinit", "#page1", function() {
//for product select autopopulate -- working //
$("#productautocomplete").live( "listviewbeforefilter", function ( e, data ) {
var $ul = $( this ),$input = $( data.input ),value = $input.val(),html = "";
$ul.html( "" );
if ( value && value.length > 2 ) {
$ul.html( "<li><div class='ui-loader'><span class='ui-icon ui-icon-loading'></span></div></li>" );
$ul.listview( "refresh" );
$.getJSON('ajax/getProductList.php', {term:$input.val()}, function(data) {
var items = [];
var str = "";
for (var key in data) {
if (data.hasOwnProperty(key)) {
var value = data[key].value;
var label = data[key].label;
var stock = data[key].stock;
var proddata = data[key].data;
str += '<li code="'+value+'" name="'+label+'" stock="'+stock+'" data="'+proddata+'">';
str += '<a data-ajax="false" rel="external">'+label+' [ '+stock+' ]</a>';
str += '</li>';
}
}
$ul.html( str );
$ul.listview( "refresh" );
$ul.trigger( "updatelayout" );
});
}
});
//end search
//on click set hidden input fields to be used in dialog box. -- working
$('#productautocomplete li').live('click', function(e) {
//--------------------fetch data ------------------------
var id = $(this).attr('code');
var name = $(this).attr('name');
var data = $(this).attr('data');
var stock = $(this).attr('stock');
//add packaging type and unit info to div data
$('#proddata').attr('data',data);
//add currstock info to div
$('#prodstock').attr('data',stock);
//----------------------hide list
$('#productautocomplete li').hide();
//----------------------place name in visible input box
$('#productsearch input').attr('value',name);
//----------------------place id in hidden input box for the actual form.
$('#formproduct').val(id);
//----------------------fill options for package + show select package div
var filteroptions = data.split(",");
$('#packing option').remove();
for (var x=0; x<3 ; x++) {
var eachoption = filteroptions[x].split(":");
//if unit wise option is less than that of stock show as option.
if (eachoption[0]!="0" && eachoption[0] <= stock.valueOf()) {
$('#packing').append($('<option>', {
value: eachoption[0]+':'+eachoption[1],
text : eachoption[1]+' [ '+eachoption[0]+' ] '
}));
}
}
});
});
//this is where the problem lies ..
//have tried with pageinit.. but that only calls it once.
$( document ).on( "pageshow", "#page3", function() {
$('#batchsel tbody').empty();
// !!!!!!!!!!!!!!!!!!!!!!! // !!!!!!!!!!!!!!!!!!!!!!! //
//doesnt fetch any of 4 following values after pageChange back to page1.
//not sure if this is due to how i'm reloading the page1.
//see function addProduct below.
var prodcode = $('#formproduct').val(); //
var prodstock = $('#prodstock').attr('data');
var prodqty = $('#qty').val();
var packing = $('#packing').find(":selected").val();
//returns undefined
alert(prodcode); alert(packing); alert(prodqty);
//always ends here when dialog opens second time.
if (!prodcode || !packing || !prodqty) {
alert("Please give all required information");
//does not close also when opens the second time.
$('#page3').dialog('close');
}
var packinginfo = packing.split(":");
var totalrequired = prodqty * packinginfo[0];
//alert(packinginfo[1]);alert(totalrequired);
if (totalrequired > prodstock ) {
alert("Not enough Stock");
$('#page3').dialog('close');
} else {
//------------------------------ Getting Batch Info ---------------------------------------------------
var rows = '';
$.getJSON('ajax/getBatchDetails.php', {code:prodcode,pack:packinginfo[1],qty:totalrequired}, function(data) {
for (var key in data) {
if (data.hasOwnProperty(key)) {
//alert (data[key].Batch);
rows += '<tr><td><input type="checkbox" class="batchcheckbox" id="batchcheckbox_'+data[key].BatchId+'" value="'+data[key].BatchId+':'+data[key].Stock+'" onchange="resetRemainingQty(this.value);""/></td><td>' + data[key].Batch + '</td><td>' + data[key].ExDt +'</td><td>' + data[key].BRate + '</td><td>' + data[key].SRate + '</td><td>' + data[key].Pack + '</td><td>' + data[key].Stock + '</td><td>' + data[key].Supname + '</td><td>' + data[key].Stax + '</td><td>' + data[key].BillDt + '</td><td>' + data[key].BillNo + '</td><td>' + data[key].btax + '</td><tr>';
}
}
$('#batchsel tbody').append(rows);
//add remaining amount in the data field of p1.
$('#remainingdata p1').attr('data',totalrequired);
$('#remainingdata p2').attr('data',totalrequired);
$('#remainingdata p1').html("<h4>Remaining Amount : "+totalrequired+"</h4>");
});
//---------------------------------------------end batch info display: -----------------------------------
}
});
function addProduct() {
//--------code info---------
var prodcode = $("#formproduct").val(); // to send
//--------packing info---------------
var packing = $('#packing').find(":selected").val();
var packinginfo = packing.split(":");
//-----------qty req ---------------------
var prodqty = $('#qty').val();
var totalrequired = prodqty * packinginfo[0]; // to send
//-------------batch info -----------
var allbatchids = "";
$('.batchcheckbox').each(function() {
if($(this).is(':checked')){
var data = $(this).val();
var datasplit = data.split(":");
var batchid = datasplit[0];
allbatchids += batchid+":";
}
});
allbatchids = allbatchids.substring(0, allbatchids.length - 1); // to send
alert(prodcode+",,"+packinginfo[1]+",,"+totalrequired+",,"+allbatchids);
//-------------- send to server to save to session ---------
$.getJSON('ajax/saveProductSession.php', {code:prodcode,pack:packinginfo[1],qty:totalrequired,batch:allbatchids}, function(data) {
if (data.error == "1") {
alert(data.message);
} else {
/// !!!!!!!! !!!!!!!!!!!!!!! !!!!!!!!!!!!!!!
///
/// the loads the page1. but jquery doesnt take val() after this.
///tried multiple variations of this but to no effect.
///removed all options.. redirect to main.php.. reloadpage:false.. etc.
///Any other way to reload the page so that the dialog once open again can
///get the values from the page1 again.
$.mobile.changePage("#page1", { reloadPage: true , dataUrl : "page1", reverse : true, changeHash: true } );
}
});
//
// $.ajax({
// type: "POST",
// url: "ajax/saveProductSession.php",
// data: { code:prodcode,pack:packinginfo[1],qty:totalrequired,batch:allbatchids }
// }).done(function() {});
}
</script>

Answer 1

Ok ! I got it to work ! thanks anyway #Gajotres. Steps :
1a. Send out the variables from main.php through changePage :
var prodcode = $('#formproduct').val();
var prodstock = $('#prodstock').attr('data');
var prodqty = $('#qty').val();
var packing = $('#packing').find(":selected").val();
$.mobile.changePage('batch.php', {
role: 'dialog',
data: {'prodcode': prodcode,'prodstock': prodstock, 'prodqty' : prodqty , 'packing' : packing},
type: 'get'
});
2a. Moved the entire div id 'page3' to a new php page named 'batch.php' where I get the variables from php and set it to the html divs.
<?php
extract($_GET);
if (!$prodcode && !$prodstock && !$packing && !$prodqty) {
header('Location: '.DEF_SITEURL."main.php");
exit;
}
?>
<div data-role="page" id="batchpage" data-url="batch.php" data-close-btn="right">
<div data-role="header">
<h1>Batch Selection</h1>
</div>
<div data-role="content">
<div style="display:none;" id="batchprodcode" data="<?php echo $prodcode; ?>"></div>
<div style="display:none;" id="batchprodstock" data="<?php echo $prodstock; ?>"></div>
<div style="display:none;" id="batchpacking" data="<?php echo $packing; ?>"></div>
<div style="display:none;" id="batchqty" data="<?php echo $prodqty; ?>"></div>
<div style="overflow:auto;">
<table id="batchsel" style="border:1px;">
<thead>
<tr>
<th></th>
<th>Batch No</th>
<th>Exp Date</th>
<th>Brate</th>
<th>Srate</th>
<th>Packing</th>
<th>Stock</th>
<th>Supplier</th>
<th>ST%</th>
<th>Bill Date</th>
<th>Bill No</th>
<th>btax</th>
</tr>
</thead>
<tbody>
</tbody>
</table>
</div>
<div id="remainingdata">
<p1 id="changeable_requirements"></p1>
<button id="saveprod" onclick="addProduct(); return false;">Add Product</button>
</div>
</div>
</div>
3a. Then I just change the pageshow that i was using for page3 to the new div that is created on batch.php. The script still runs on main.php.
$( document ).on( "pageshow", "#batchpage", function() {
$('#batchsel tbody').empty();
var prodcode = $('#batchprodcode').attr('data');
var prodstock = $('#batchprodstock').attr('data');
var prodqty = $('#batchqty').attr('data');
var packing = $('#batchpacking').attr('data');
...
});