Read Selected Tree Node value. Jdeveloper Jdeveloper 11.1.2.1.0 11.1.2.1.0

Question

Version: Jdeveloper 11.1.2.1.0
how to get programmatically tree node value.
i have tried but cann't read value from selected node.
please help me.
here is my application creation steps:
1. New Application
2. Fusion Web Application (ADF) Template
3. Create View Object VOTreeMst
Query:
     Select Department_Name,Department_Id
     From Departments
4. Create View Object VOTreeChd
Query:
     Select Last_Name,Employee_Id,Department_Id
     From Employees
5. Create View Link VLTreeMstChd
     VOTreeMst.DepartmentId=VOTreeChd.DepartmentId
     And Add to Application Module
6. Create page page1 in ViewController
     New-->Web Tier-->JSF/Facelets-->Page
     Selected Document Type JSP XML
7. Drag VOTreeMst1 From Data Controls into page1
and select Tree-->ADF Tree
8. ADD java Code into selection Listener
public void nodeSelect(SelectionEvent selectionEvent) {
//original selection listener set by ADF
String adfSelectionListener = "#{bindings.VOTreeMst1.treeModel.makeCurrent}";
//make sure the default selection listener functionality is preserved.
//you don't need to do this for multi select trees as the ADF binding
//only supports single current row selection
/* START PRESERVER DEFAULT ADF SELECT BEHAVIOR */
FacesContext fctx = FacesContext.getCurrentInstance();
Application application = fctx.getApplication();
ELContext elCtx = fctx.getELContext();
ExpressionFactory exprFactory = application.getExpressionFactory();
MethodExpression me = null;
me = exprFactory.createMethodExpression(elCtx, adfSelectionListener, Object.class,
new Class[] { SelectionEvent.class });
me.invoke(elCtx, new Object[] { selectionEvent });
/* END PRESERVER DEFAULT ADF SELECT BEHAVIOR */
RichTree tree = (RichTree)selectionEvent.getSource();
TreeModel model = (TreeModel)tree.getValue();
//get selected nodes
RowKeySet rowKeySet = selectionEvent.getAddedSet();
Iterator rksIterator = rowKeySet.iterator();
//for single select configurations, thi sonly is called once
while (rksIterator.hasNext()) {
List key = (List)rksIterator.next();
JUCtrlHierBinding treeBinding = null;
CollectionModel collectionModel = (CollectionModel)tree.getValue();
treeBinding = (JUCtrlHierBinding)collectionModel.getWrappedData();
JUCtrlHierNodeBinding nodeBinding = treeBinding.findNodeByKeyPath(key);
Row rw = nodeBinding.getRow();
//print first row attribute. Note that in a tree you have to determine the node
//type if you want to select node attributes by name and not index
String rowType = rw.getStructureDef().getDefName();
if(rowType.equalsIgnoreCase("VOTreeMst")){
System.out.println("This row is a department: " + rw.getAttribute("DepartmentId"));
else if(rowType.equalsIgnoreCase("VOTreeChd")){
System.out.println("This row is an employee: " + rw.getAttribute("EmployeeId"));
else{
System.out.println("Huh ????");
// ... do more usefuls stuff here
9. when i click on first node it is working but i click on second node it is not working
error message::
<LifecycleImpl> <_handleException> ADF_FACES-60098:Faces lifecycle receives unhandled exceptions in phase INVOKE_APPLICATION 5
javax.el.ELException: java.lang.NullPointerException
     at com.sun.el.parser.AstValue.invoke(Unknown Source)
     at com.sun.el.MethodExpressionImpl.invoke(Unknown Source)
     at org.apache.myfaces.trinidad.component.UIXComponentBase.broadcastToMethodExpression(UIXComponentBase.java:1589)
     at org.apache.myfaces.trinidad.component.UIXTree.broadcast(UIXTree.java:237)
<RegistrationConfigurator> <handleError> ADF_FACES-60096:Server Exception during PPR, #1
javax.el.ELException: java.lang.NullPointerException
I have also tried using following code but same problem
public void onTreeSelect(SelectionEvent selectionEvent) {
//original selection listener set by ADF
String adfSelectionListener = "#{bindings.VOTreeMst1.treeModel.makeCurrent}";
//make sure the default selection listener functionality is preserved.
//you don't need to do this for multi select trees as the ADF binding
//only supports single current row selection
/* START PRESERVER DEFAULT ADF SELECT BEHAVIOR */
FacesContext fctx = FacesContext.getCurrentInstance();
Application application = fctx.getApplication();
ELContext elCtx = fctx.getELContext();
ExpressionFactory exprFactory = application.getExpressionFactory();
MethodExpression me = null;
me = exprFactory.createMethodExpression(elCtx, adfSelectionListener, Object.class,
new Class[] { SelectionEvent.class });
me.invoke(elCtx, new Object[] { selectionEvent });
/* END PRESERVER DEFAULT ADF SELECT BEHAVIOR */
RichTree tree = (RichTree)selectionEvent.getSource();
TreeModel model = (TreeModel)tree.getValue();
//get selected nodes
RowKeySet rowKeySet = selectionEvent.getAddedSet();
Iterator rksIterator = rowKeySet.iterator();
//for single select configurations, thi sonly is called once
while (rksIterator.hasNext()) {
List key = (List)rksIterator.next();
JUCtrlHierBinding treeBinding = null;
treeBinding = (JUCtrlHierBinding)((CollectionModel)tree.getValue()).getWrappedData();
JUCtrlHierNodeBinding nodeBinding = treeBinding.findNodeByKeyPath(key);
Row rw = nodeBinding.getRow();
//print first row attribute. Note that in a tree you have to determine the node
//type if you want to select node attributes by name and not index
System.out.println("row: " + rw.getAttribute(0));
But
If i create .jspx page From
Web Tier->Jsp->page Then it is working fine
when i create .jspx page From
Web Tier->JSF\Facelets->page Then it is not working
i need to get value from "Web Tier->JSF\Facelets->page"
is there any help please?

Answer 1

You should try Franks generic selectionListener http://www.oracle.com/technetwork/developer-tools/adf/learnmore/25-generic-tree-selection-listener-169164.pdf. For help on hoe to get the selected tree node data check http://www.oracle.com/technetwork/developer-tools/adf/learnmore/26-get-selected-tree-node-data-169165.pdf
Timo