SAP Web Dynpro Java - Adding a new Item row to an existing model object

As part of a proof of concept (PoC) for one of my clients, I had to create a purchase order form which had multiple items against it - using an Adobe Form in Adobe Lifecycle Forms Designer. Some articles suggested that a JavaScript client side call (e.g. Table1.Row1.instanceManager.addInstance(1); would work - but in Adobe Document Services, this would never render for me - even if I forced the render to the most recent version of Adobe (9.0). It was suggested by SAP consultants that we should just be doing a full post back to the server and adding items in the server side Java code instead.

For adding items in a dynamic table like this on the server side (using the SAP Purchase Order Create Web Service (PurchaseOrderCreateRequestConfirmation_In, SAP ECC604), see below:

  public void onActionAddItemRow(com.sap.tc.webdynpro.progmodel.api.IWDCustomEvent wdEvent )
  {
    //@@begin onActionAddItemRow(ServerEvent)

// Here we get the current parent node of the model from the view 
// context to which we want to add the item row
   
 com.sap.demo.jrd.readpobyws.wd.readpowsmodel.PurchaseOrder poN = wdContext.currentPurchaseOrderElement().modelObject(); 

// Here we create a new, empty instance of the item row casting
// to the correct model class by using the associated model property
// of the parent node
// Note that at this point the instance is not yet bound to the item

 com.sap.demo.jrd.readpobyws.wd.readpowsmodel.Item itemN = new Item((ReadPOWSModel) poN.associatedModel());

// Here we create an instance of a subnode of Item using the same
// approach
 com.sap.demo.jrd.readpobyws.wd.readpowsmodel.SHORT_Description descN = new SHORT_Description((ReadPOWSModel) poN.associatedModel()); 

// If you wish to set default values in the leaf elements this is how
 descN.set$0023SimpleContent("New item");
 itemN.setID("99");

// Here we put the subnode for the Description into the parent Item
 itemN.setDescription(descN);

// Here we create an instance of the subnode for the Accounting Coding 
// Block Assignment using the same approach
 com.sap.demo.jrd.readpobyws.wd.readpowsmodel.PurOrdERPItmByAcctgCodgBlkDistrRsp_SAcctgCodgBlkAssgmt aCBAsN = new PurOrdERPItmByAcctgCodgBlkDistrRsp_SAcctgCodgBlkAssgmt((ReadPOWSModel) poN.associatedModel());

// If you wish to set default values this is the example:
 aCBAsN.setAccountDeterminationExpenseGroupCode("0000112000");
 
// Here we create an instance of the subnode for the Accounting Coding
// Block Distribution, i.e. the parent of the ACB Assignment
com.sap.demo.jrd.readpobyws.wd.readpowsmodel.PurOrdERPIdRsp_SAcctgCodgBlkDistr aCBDN = 
  new PurOrdERPIdRsp_SAcctgCodgBlkDistr((ReadPOWSModel) poN.associatedModel());

// Here we put the subnode for the ACB Assignment into the 
// parent ACB Distribution
 aCBDN.addAccountingCodingBlockAssignment(aCBAsN);

// Here we put the subnode ACB Distribution into the parent item
 itemN.setAccountingCodingBlockDistribution(aCBDN);
 
// Finally – once the substructure has been built, we add the item 
// to the purchase order node – i.e. set the item as a new row 
 poN.addItem(itemN);


    //@@end
  }