
When i check in the Debug logs the value gets calculated but it does not get changed in the visual force page.Any help very much appreciated.for (integer i=0; i < OPplineitem.size(); i++) {
tempObj = new wrapperClass();
tempObj.productname= OPplineitem[i].PricebookEntry.Product2.Name;
tempObj.BinItemCode=OPplineitem[i].Bin_Item_Code__c;
tempObj.quantity=OPplineitem[i].Quantity;
tempObj.totalamount=OPplineitem[i].Sys_total_Amount__c;
// tempObj.Subtotal =OPplineitem[i].Opportunity.Subtotal__c;
// tempObj.NonPickTotal=OPplineitem[i].Opportunity.Non_Pick_Total__c;
//Add a conditional statement here
if (OPplineitem[i].PricebookEntry.Product2.Product_Line__c=='DIE') {
tempObj.unitprice=0.01;
tempobj.extension=OPplineitem[i].Quantity * tempObj.unitprice;
tempObj.productname=OPplineitem[i].Bin_Item_Code__c;
if (i==0) {
tempObj2.Subtotal=tempobj.extension;
system.debug('@@@@@@@@'+tempObj2.Subtotal);
} else {
tempObj2.Subtotal=tempObj2.Subtotal+tempObj.extension;
}
} else {
tempObj.unitprice=1;
//tempObj.unitprice=OPplineitem[i].ListPrice;
tempobj.extension=OPplineitem[i].Extension__c ;
}
}

you have to add these fields to class InvoiceController, not to the method!! In method you will calculate them!