Action (event) for a tree problem

[Former Member]

Hi all,

I have created a recursive Web Dynpro Tree as described in the document 'Constructing a Recursive and Loadable Web Dynpro Tree'.

However I have the following problem:

In the view-designer I created a action (in the action tab). I named the action 'LoadToolChildren'. (I could not use 'LoadChildren' because this action already exists for another Web Dynpro Tree).

The method I have implemented look as follows:

  //@@begin javadoc:onActionLoadToolChildren(ServerEvent)
  /** Declared validating event handler. */
  //@@end
  public void onActionLoadToolChildren(com.sap.tc.webdynpro.progmodel.api.IWDCustomEvent wdEvent, com.asml.tpd.distribution.components.wdp.IPrivateBomTableView.IToolTableElement element )
  {
    //@@begin onActionLoadToolChildren(ServerEvent)
	String nc12 = element.getNC12();

	TypedBom typedBom = wdThis.wdGetTPD_DistributionController().getBom(nc12);
	addToolChildren(typedBom.getBom(), element);
	
	IPrivateBomTableView.IToolTableNode node = wdThis.wdGetContext().nodeToolTable();
	node.setTreeSelection(node.getElementAt(0));
    //@@end
  }

However, no matter what I try, I always get a nullpointer because the parameter element seems to be null.

I have no idea how this is possible, I checked every property but everything seems to be fine.

Can somebody please help me on this, I have been stuck on this for three days now!

Regards,

Harm de Laat

[Former Member]

Did you define an event parameter mapping for the IWDTreeNodeType.onLoadChildren event?

Something like

wdDoModifyView(...)
{
  if (firstTime)
  {
    IWDTreeNodeType nodeType = (IWDTreeNodeType) view.getElement("<ID-of-node-type>");
    nodeType.mappingOfOnLoadChildren().addSourceMapping
    (
      "path", /* name of event parameter */
      "element" /* name of action parameter */
    );
  }
}

Armin