Show end user the corresponding elements of list .

Question

Hi
I have created two tables with relationship as following :
SQL> create table students( stud_id number ,stud_name varchar2(220) primary key);
Table created.
SQL> create table class (class_id number,class_name varchar2(50) primary key);
Table created.
SQL> alter table class add(stud_name varchar2(220) references students(stud_name));
Table altered.
I created a form for each table in one block.
I changed stud_name text item in students form to a list item
I changed class_name text item in class form to a list item
I changed stud_name text item in class form to a list item
Iwant to do two things.
first thing
to add all students names that I saved in database to elements of the list in the students form programmaticaly
second thing
A suitable recordgroup query + a code to show the end user all list of corresponding stud_name when he/she chooses a specific class_name
I will be glad if someone help me.
regards.

Answer 1

Thank you sir/andreas Weiden for your response.
I followed your link.
I created a new form against class table and named it class,
I setted the item type of class_name and stud_name to list item.
then I went to the property pallete of the class_name ,choosing elements in the list I setted the list item value to :class.class_name, and gived the initial value the same value :class.class_name.
doing the same thing to stud_name, of course the value here is
:class.stud_name.
I created a pre_form trigger and wrote the following code
DECLARE
  rg RECORDGROUP;
  nDummy NUMBER;
BEGIN
  rg:=CREATE_GROUP_FROM_QUERY('RG', 'SELECT   stud_NAME LABEL   , TO_CHAR(class_name) VALUE FROM class   ORDER BY 2');
  nDummy:=POPULATE_GROUP(rg);
  POPULATE_LIST('class.stud_name', rg);
END;When running the stud_name saved in database are displayed, but class_name
are not .
what is the problem.
please help.
thank you again.