How to get the element label in an List Item, Forms 4.5

Jocke

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Mar 16, 1998, 3:00:00 AM3/16/98

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Hello

I've got a question about list items.

I'm using a combo box to show values from a table
where the column is an ID column and the shown labels
are fetched into a record group from an other table.

Is there a way to get the current label from the listbox ?

The built-in GET_LIST_ELEMENT_LABEL can get labels out of
a list item, but it needs a list_index as argument, and I do not
know how to get this list_index for the current label.

Thanks

/Jocke

Jhansi Rani

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Mar 16, 1998, 3:00:00 AM3/16/98

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Jocke wrote:
Hi,
Is it not possible for you to use LOV ( List of Values ) facility of
forms for your purpose ?

Cheers
Jhansi

Neville Sweet

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Mar 17, 1998, 3:00:00 AM3/17/98

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Jocke,

The Help example for Get_List_Element_Count points to one solution, which
is to loop through the List and, when the ID value matches the current
value of your list item, use Get_List_Element_Value.

You could do this whenever required or use a When-List-Changed trigger to
save the label for the current list item in a separate text item (not
displayed on the canvas). Either way I am not aware of an easy solution
that avoids looping through the list.

Jocke <h...@abb.se> wrote in article <01bd50c0$ca60db10$d26add8a@pc2095>...

Neville Sweet

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Mar 18, 1998, 3:00:00 AM3/18/98

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Jocke,

As you may already know from my previous posting, the reference to
Get_List_Element_Value
should be Get_List_Element_Label.

There are also errors in the Forms example for Get_List_Element_Count,
whereby list_id is undefined and the first loop should use
Get_List_Element_Label.

I would suggest you do something similar to the following:

DECLARE
list_id ITEM := Find_Item(your_block.list_item);
total_list_count NUMBER(2);
loop_index_var NUMBER(2) := 0;
list_value VARCHAR(50);
list_label VARCHAR(50);

BEGIN
/*
** Determine the total number of list elements.
*/
total_list_count := Get_List_Element_Count(list_id);
/*
** Compare the current list item to the list element values.
*/
WHILE loop_index_var < total_list_count
AND list_label = NULL
LOOP
loop_index_var := loop_index_var + 1;
list_value := Get_List_Element_Value(list_id, loop_index_var);
/*
** All list values are unique, so if it matches, get the Label.
*/
IF your_block.list_item = list_value THEN
list_label := Get_List_Element_Label(list_id, loop_index_var);
END IF;
END LOOP;
/*
** If you want to access the label outside this procedure, save it
** in a Control item or some other non-display item.
*/
Control_block.item := list_label;
END;

Hope this is what you're looking for,
Neville Sweet <sweet.ne...@bhp.com.au.no_junk_today_thanks>

Brian Membrey

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Mar 18, 1998, 3:00:00 AM3/18/98

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It's horrible, but you need to search the list to determine the label (and
index) The following code snippet should put you on the right track ...
it searches the list for the currently selected value and returns the label
(I've hacked it out of another function, but it should be close to the
mark)

FUNCTION GET_LIST_LABEL (from_list_name VARCHAR2)
RETURN VARCHAR2 IS

list_id ITEM := FIND_ITEM(from_list_name);
list_count NUMBER;
current_value VARCHAR2(50);
clicked_value VARCHAR2(50) := NAME_IN(from_list_name);
clicked_label VARCHAR2(50);
list_not_found EXCEPTION;
BEGIN

IF NOT ID_NULL(list_id) THEN

list_count := GET_LIST_ELEMENT_COUNT(list_id);
FOR i IN 1..list_count LOOP
current_value := GET_LIST_ELEMENT_VALUE(list_id, i);
IF clicked_value = current_value THEN
clicked_label := GET_LIST_ELEMENT_LABEL(list_id, i);
RETURN clicked_label'
EXIT;
END IF;
END LOOP;
ELSE
RAISE list_not_found;
END IF;
EXCEPTION
WHEN list_not_found THEN
MESSAGE('List name ' || from_list_name ||
' not found in GET_LIST_ELEMENT');
RAISE FORM_TRIGGER_FAILURE;
END;