Search by child attributes on a tree table

This example illustrates search functionality on a tree table (based  on both master and child record attributes). Steve discusses similar topic in one of his blog post http://blogs.oracle.com/smuenchadf/examples/ Example #150. This post is also based on the same idea (slightly differ, from implementation perspective).

Let me detail the use case with classic Department-Employee example. Your tree table may looks like as shown below. Search mechanism should enable user to search based on attributes both from parent and child records, i.e. Department and Employee entities.

-DeptID , DeptName
|
|__EmpId1, Firstname1, Email1
|__EmpId2, Firstname2, Email2

Obviously implementation part involves two ViewObjects, one for Department and the other for Employee. Next step is to define a ViewCriteriathat act as model for the query. Below image shows a ViewCriteria defined on DeprtmentViewObject.

Define another ViewCriteria on EmployeeViewOject, to filter out the 'Employee' child records programmatically. Please note that, this is used from overridden DepartmentViewObjectImpl::createViewLinkAccessorRS() method as detailed below.

To enable search across child rows(Employee records), I overrode the ViewObjectImpl::createViewLinkAccessorRS(---) as given below(in the DeprtmentViewObjectImpl). This method contains the filtering logic for child rows(Employees).

 @Override
 protected ViewRowSetImpl createViewLinkAccessorRS(AssociationDefImpl associationDefImpl,
                                                     ViewObjectImpl viewObjectImpl,
                                                      Row row,
                                                      Object[] object) {
   ViewRowSetImpl viewRowSetImpl =
       super.createViewLinkAccessorRS(associationDefImpl,
       viewObjectImpl,row, object);
     
   String firstName = getbndVarFirstName();
   if (firstName != null && firstName.trim().length() > 0) {
      ViewCriteriaManager vcm = viewObjectImpl.getViewCriteriaManager();
      ViewCriteria vc = vcm.getViewCriteria("EmployeesViewCriteria");
      VariableValueManager vvm = vc.ensureVariableManager();
      vvm.setVariableValue("bndVarFirstName", getbndVarFirstName());
      viewObjectImpl.applyViewCriteria(vc);
      } else {

         viewObjectImpl.removeApplyViewCriteriaName("EmployeesViewCriteria");
      }

      return viewRowSetImpl;
 }

Rest of the steps remains same as for a normal tree table creation.

You can download the sample workspace from here. This example illustrates the above said use case -Search by child attributes on a tree table.
Run the test.jspx from the attached project. Search panel displays two fields, DepartmentName and FirstName. DepartmentName is used to search the parent record of the tree table, and FirstName filters out the child records.
[Runs with Oracle JDeveloper 11g R1 PS1 + HR Schema]