I have a DataService that uses the Assembler interface approach (I
subclassed AbstractAssembler). When I update one item in the managed
Collection and commit it (autoCommit is false) I'm getting a
PropertyChangeEvent of kind UPDATE for each item in the Collection from
the DataService. In addition I get a CollectionEvent of kind REMOVE for
each item in the Collection, then a CollectionEvent of kind ADD for each
item in the Collection from the Collection itself.
I'm assuming this is because the fill() is being called after the update
is completed. How do I commit/update the individual item so that I only
get an event (or set of events) for the item that was modified? Is that
possible when using a managed Collection or do I need to operate at the
individual item level. Am I doing something wrong (or not doing
something at all) in the Assembler?
I'm very experienced with Remoting and Messaging but this is my first
time dealing with DataServices. Any help, samples,etc. are greatly
appreciated. Thanks.
Here's the Assembler code...
public class MyAssembler extends AbstractAssembler {
private MyService svc = MyService.getInstance();
public Collection fill(List fillParameters) {
if (fillParameters.size() >= 2) {
int fillType = FlexDataHelper.getIntPrimitive( fillParameters.get(0) );
Long companyId = FlexDataHelper.getLong( fillParameters.get(1) );
switch(fillType) {
case QueryType.ALL_WIDGETS_FOR_COMPANY:
return svc.getAllWidgets(companyId);
case QueryType.ACTIVE_WIDGETS_FOR_COMPANY_:
return svc.getActiveWidgets(companyId);
case QueryType.WIDGETS_BY_COMPANY_AND_CATEGORY:
if (fillParameters.size() == 3) {
Integer categoryId = FlexDataHelper.getInteger( fillParameters.get(2) );
return svc.getWidgets(companyId, categoryId);
}
}
}
// Throws a nice error
return super.fill(fillParameters);
}
public Object getItem(Map uid) {
return svc.getWidget( FlexDataHelper.getLong(uid.get("companyId")),
FlexDataHelper.getInteger(uid.get("widgetId")) );
}
public void createItem(Object newVersion) {
svc.saveWidget((WidgetValue)newVersion);
}
public void updateItem(Object newVersion, Object prevVersion, List
changes) {
try {
svc.saveWidget((WidgetValue)newVersion);
} catch (Exception e) {
Long companyId = ((WidgetValue)prevVersion).getCompanyId();
Integer widgetId = ((WidgetValue)prevVersion).getWidgetId();
System.err.println("*** Throwing DataSyncException when trying to save
widget = " + widgetId);
throw new DataSyncException(svc.getWidget(companyId, widgetId), null);
}
}
public void deleteItem(Object prevVersion) {
try {
svc.deleteWidget( (WidgetValue)prevVersion );
} catch (Exception e) {
Long companyId = ((WidgetValue)prevVersion).getCompanyId();
Integer widgetId = ((WidgetValue)prevVersion).getWidgetId();
System.err.println("*** Throwing DataSyncException when trying to delete
widget = " + widgetId);
throw new DataSyncException(svc.getWidget(companyId, widgetId), null);
}
}
Here's the Flex UI code...
public function getWidgetsForCompany( company:CompanyValue ):void {
var widgets:ArrayCollection = new ArrayCollection();
var call:AsyncToken = widgetService.fill(widgets,
QueryType.ALL_WIDGETS_FOR_COMPANY, company.companyId);
// Add a reference to the collection that will be filled for access by
the responder
call.useLocalData = true;
call.localData = widgets;
call.addResponder( responder );
}
public function saveWidget( widget:WidgetValue ):void {
var call:AsyncToken;
if (isNaN(widget.widgetId)) {
call = widgetService.createItem(widget);
} else {
//Update
call = widgetService.commit(new Array(widget), false);
}
call.addResponder( responder );
}
