How to highlight a tree node programmatically

Question

Problem
=====
Just like a typical management software, I have a navigation tree presenting a list of objects (let's say toasters) on the left panel. The content panel on the right side presents the details of a toaster, when the user selects the toaster on the navigation tree. On the toaster details panel, I would like to have a hyper link referring to another toaster - associated to the selected toaster. On clicking on the hyperlink, I would like to display the details of the associated toaster and the navigation tree node for the associated toaster being highlighted.
For example, BUI presents the following now:
+ Toasters | Toaster 1 Details [Refresh]
+ <toaster1> |
+ toaster2 | ... toaster3
+ toaster3 |
toaster1 is selected on the navigation tree. The contents panel displays Toaster 1 details, which has a hyper link for toaster3.
When the user click on toster3 on the contents panel, I would like to see the following
+ Toasters | Toaster 3 Details [Refresh]
+ toaster1 |
+ toaster2 | ...
+ <toaster3> |
My Trial
=====
ADF Rich Client 11.1.2.3 is used for my development.
Jspx code for the navigation tree looks like this:
<af:tree id="navTree" ...>
<f:facet name="nodeStamp">
<af:panelGroupLayout id="nodePgl">
<af:switcher facetName="#{stamp.outcome!=null?'actnode':'noactnode'}" ...>
<f:facet name="actnode">
<af:commandLink id="leafLink" text="#{stamp.label}" action="#{stamp.actionOutcome}">
<af:setActionListener from="#{stamp.key}" to="#{treeHandler.selectedMenuItem}"/>
</af:commandLink>
</f:facet>
<f:facet name="noactnode">
<af:outputText id="notLeafText" value="#{stamp.label}"/>
</f:facet>
</af:switcher>
</af:panelGroupLayout>
</f:facet>
</af:tree>
The hyper link on the contents panel looks like this:
<af:iterator var="toaster" value="#{toastData.toasters}">
<af:commandLink text="#{toaster}" action="#{toasterHandler.goToToaster}">
<f:param name="toasterId" value="#{toaster}"/>
<af:setActionListener from="#{toaster}" to="#{treeHandler.selectedToaster}"/>
</af:commandLink>
</af:iterator>
I got some tips from this forum (cannot find thread at the moment) and implemented the treeHandler.selectedToaster method as follows:
// getSelectionState returns selStat, which is instantiated like the following:
// RowKeySet selStat = new RowKeySetTreeImpl();
// TreeModel model = (TreeModel) menuModel.getWrappedData();
// selStat.setCollectionModel(model);
// selStat.setContained(true);
RowKeySet rowKeySet = getSelectionState();
rowKeySet.removeAll();
// synthesize the rowKey for the selected toaster
// if the toaster found in the toaster node list,
// rowKey should look like [0, <rowIdx of toaster>]
ArrayList<Integer> rowKey = new ArrayList<Integer>();
rowKey.add(0);
rowKey.add(new Integer(rowIdx));
TreeModel model = (TreeModel) menuModel.getWrappedData();
model.setRowKey(rowKey);
model.setRowIndex(rowIdx);
rowKeySet.add();
This seems to work most of times except when I refresh the contents details panel using partial page rendering.
I get NullPointerException on the call to rowKeySet.removeAll().
Caused by: java.lang.NullPointerException
     at org.apache.myfaces.trinidad.model.RowKeySetTreeImpl._selectAll(RowKeySetTreeImpl.java:459)
     at org.apache.myfaces.trinidad.model.RowKeySetTreeImpl.removeAll(RowKeySetTreeImpl.java:146)
In my observation, this NPE happens when rowKeySet.size() returns 1 but rowKeySet.iterator() does not return any entries.
I suspect this is a bug on RowKeySetTreeImpl but not sure.
Help Need
=======
1. What is the reasonably right way to highlight the tree node for my problem?
2. If my trial is one way to do it, how can I get around the NPE? I cannot change ADF Rich Client library at this point.
Any help/suggestion/advise would be appreciated.
Thanks,
Jeongtae

Answer 1

I did this, to programmatically expand a tree node, you can try the same and set the row key to highlight.
private RowKeySet disclosedTreeRowKeySet = new RowKeySetImpl();
public void rowDisclosureListener(RowDisclosureEvent rowDisclosureEvent)
Iterator added = rowDisclosureEvent.getAddedSet().iterator();
if (added!=null)
while (added.hasNext())
Object rowKey = added.next();
//disclosedTreeRowKeySet.clear();
List path = (List)rowKey;
for( int i=0; i< path.size(); i++ )
List<Object> nodePath = new ArrayList<Object>();
for( int j=0; j<i; j++ )
nodePath.add( path.get( j ) );
disclosedTreeRowKeySet.add( nodePath );
disclosedTreeRowKeySet.add( rowKey );
System.out.println( "disclosed Keys...... " + disclosedTreeRowKeySet );
private void expandSelectedNode(RowKeySet addedObj) {
if (sourceTreeTable != null) {
Iterator added = (Iterator)addedObj.iterator();
if (added!=null)
while (added.hasNext())
Object rowKey = added.next();
List path = (List)rowKey;
for( int i=0; i< path.size(); i++ )
List<Object> nodePath = new ArrayList<Object>();
for( int j=0; j<i; j++ )
nodePath.add( path.get( j ) );
disclosedTreeRowKeySet.add( nodePath );
disclosedTreeRowKeySet.add( rowKey );
sourceTreeTable.setDisclosedRowKeys(disclosedTreeRowKeySet);
}