LiveCycle DS , can't get the return value of fill( arg) from Assembler class

Question

Hi all!
I'm a have small problem , can any one help me? Please
I make a project which very similar to Product project(in
example).
1) Have Assembler class: I work correctly
package flex.samples.stock;
import java.util.List;
import java.util.Collection;
import java.util.Map;
import flex.data.DataSyncException;
import flex.data.assemblers.AbstractAssembler;
public class StockAssembler extends AbstractAssembler {
public Collection fill(List fillArgs) {
StockService service = new StockService();
System.out.print(fillArgs.size());
return service.getStocks();
public Object getItem(Map identity) {
StockService service = new StockService();
return service.getStock(((Integer)
identity.get("StockId")).intValue());
public void createItem(Object item) {
StockService service = new StockService();
service.create((Stock) item);
public void updateItem(Object newVersion, Object
prevVersion, List changes) {
StockService service = new StockService();
boolean success = service.update((Stock) newVersion);
if (!success) {
int stockId = ((Stock) newVersion).getStockId();
throw new DataSyncException(service.getStock(stockId),
changes);
public void deleteItem(Object item) {
StockService service = new StockService();
boolean success = service.delete((Stock) item);
if (!success) {
int stockId = ((Stock) item).getStockId();
throw new DataSyncException(service.getStock(stockId),
null);
some require class is ok.
2) I configure in data-management-config.xml
<destination id="stockinventory">
<adapter ref="java-dao" />
<properties>
<source>flex.samples.stock.StockAssembler</source>
<scope>application</scope>
<metadata>
<identity property="StockId"/>
</metadata>
<network>
<session-timeout>20</session-timeout>
<paging enabled="false" pageSize="10" />
<throttle-inbound policy="ERROR" max-frequency="500"/>
<throttle-outbound policy="REPLACE"
max-frequency="500"/>
</network>
</properties>
</destination>
3) My client app:
I use :
<mx:ArrayCollection id="stocks"/>
<mx:DataService id="ds" destination="stockinventory"/>
ds.fill(stocks); --> Problem here
When I run this app, The StockAssembler on the server work
correctly (i use printout to debug) . But variable stocks can't get
the return value,it is a empty list.
Please help me!

Answer 1

Hi,                                                             
The executeQueryAsync method is “asynchronous, which means that the code will continue to be executed without waiting for the server to
respond”.
From the error message “The collection has not been initialized”, which suggests that the object in use hadn’t been initialized after the execution of the executeQueryAsync method.
I suggest you debug the code in browser to see which line of code will throw this error, then you can reorganize the logic of the code to avoid using the uninitialized object.
A documentation from MSDN about Using the F12 Developer Tools to Debug JavaScript Errors
for your reference:
http://msdn.microsoft.com/en-us/library/ie/gg699336(v=vs.85).aspx
Best regards
Patrick Liang
TechNet Community Support