Using two T lists i want to create a UI, from which user can make selection

Question

I want to create a UI in forms 6i, wherein there will be two T lists on the same canvas. I'll populate the left one from the record group and then make selections to the right one using four buttons in between.
I'm using the add_list_element, delete_list_element, get_list_element_label, get_list_element_value built ins to do that. But it is not working properly. Giving a lot of forms errors.
The same thing can be done in JDeveloper using a shuttle bean.
An example of the UI that i want to construct :
The kind of UI that i'm talking can be seen when we construct a new form manually, then we goto data block wizard. There we browse for a table and the wizard gives the list of the columns for that table, from this list selections can be done using the four buttons in the same way that i intend my form to do. This is the kind of UI i want to develop.
I'm very new to development in forms. I'm sure you people at OTN will help me.
Thanks,
Abhishek.

Answer 1

Hi Abhishek
What is happening by these
Copy(v_value, p_tlist_into); and
...This commans set list item value (list selection).
The most simple way to move all elements between lists is to populate the target list from record group, and the to clear the source list. The lack of the given method - order of elements will be same, as in group.
PROCEDURE Move_All_Elements (p_tlist_from VARCHAR2, p_tlist_into VARCHAR2) is
v_value VARCHAR2(100);
v_label VARCHAR2(100);
v_index_from NUMBER;
v_index_into NUMBER;
v_count_from NUMBER; -- Count elements of tlist_out
BEGIN
--v_index_from := Get_List_element_count(p_tlist_from);
-- Get_List_element_count never return zero!
v_index_from := Get_List_Current_Index(p_tlist_from);
if v_index_from = 0 then -- The source list is enpty
--fnd_message.debug('elements=0, so return');pause;
RETURN;
end if;
--v_index_into := Get_List_element_count(p_tlist_into);
v_index_into := Get_List_Current_Index(p_tlist_into);
if v_index_into = 0 then -- The target list contant only DEFAULT value
--fnd_message.debug('no elements, so clearing the list');pause;
clear_list(p_tlist_into);
end if;
v_count_from := Get_List_element_count(p_tlist_from);
FOR i IN 1..v_count_from
LOOP
v_label := Get_List_Element_Label(p_tlist_from, i);
v_value := Get_List_Element_Value(p_tlist_from, i);
--Add_List_Element(p_tlist_into, v_index_into, v_label, v_value);
Add_List_Element(p_tlist_into, v_index_into+i, v_label, v_value);
-- The commands are lower in a loop are not necessary.
-- The commands after the loop make too most.
--Copy(v_value, p_tlist_into);
--Delete_List_Element(p_tlist_from, i);
--v_index_from := Least(v_index_from, Get_List_Element_Count(p_tlist_From));
--v_value := Get_List_Element_Value(p_tlist_from, v_index_from);
--v_value := Get_List_Element_Value(p_tlist_from, v_index_from + v_index_into);
--Copy (v_value, p_tlist_from);
--fnd_message.debug('done for one element');pause;
--exit when v_label is null;
END LOOP;
clear_list(p_tlist_from);
v_value := Get_List_Element_Value(p_tlist_into, v_count_from + v_index_into);
Copy (v_value, p_tlist_into);
EXCEPTION
when others then null;
END;