How to access APEX variables within compiled pl/sql function.

Question

Hi,
My initial problem is to create pl/sql code returning column names for my custom calendar report.
There are 7 columns for each day of the week and I want it to be on two rows - first the day of the week, such as 'Monday' and below it (with BR tag) the date, such as '18-08-2008'.
What I want is to set additional tags for underline, italics, etc. on the column heading which date is currently selected for viewing (I have DATE item for this purpose).
But as the code is getting quite complex, I decided to write a function in my schema that would return the column delimited values for the headings.
What I can't do is the following.
1) How do I reference an APEX item value, such as my DATE item? using v('P4_DATE') results in unknown function 'v'.
2) How do I use char-date and vice versa conversion using the already set application format mask, available in APEX 3.1? So that when I change the date format mask within the application, it would still work.
10x and I hope I'm not repeating s.o. else's question.

Answer 1

Hi,
I won't try to create the entire function here, just enough to point you in the right direction.
Create a function something like:
create or replace FUNCTION "GETHEADINGS" (inDATE IN VARCHAR2, inFORMAT IN VARCHAR2)
RETURN VARCHAR2
IS
BEGIN
  DECLARE
    vTHISDATE DATE;
    vSTRING VARCHAR2(1000);
  BEGIN
    vTHISDATE := TO_DATE(inDATE, inFORMAT);
    vSTRING := TO_CHAR(vTHISDATE, inFORMAT);
    RETURN vSTRING;
  END;
ENDinDate would receive the item's date value and inFORMAT receives the date format. vTHISDATE converts the date supplied into a date using the date format and vSTRING turns that into a string, again using the date format. Obviously, this example will just return the original date.
To add styling to any column, just surround the column text with the appropriate tags whilst building up your string. For example:
'<i>' || columnheading || '</i>'Now, in your report's Report Attributes, change the Headings Type to PL/SQL and enter in something like:
DECLARE
vHEADINGS VARCHAR2(1000);
BEGIN
SELECT GETHEADINGS(:P1_DATE_FIELD, :PICK_DATE_FORMAT_MASK) INTO vHEADINGS FROM DUAL;
RETURN vHEADINGS;
END;When you've created the function you need, the string returned should be in the column headings delimited with colons.
Andy