When I first started developing in APEX (back when it was called HTMLDB) I had a requirement for a tabular form. I tried to use the standard tabular forms but it was very limited and I couldn’t customize it to meet my requirements. I had poked around on the APEX forum, but wasn’t able to find a reasonable solution.
After several iterations, I have come up with a process that works extremely well. It is slightly labor intensive but it has met all the requirements each time. Please note that Patrick Wolf, http://www.inside-oracle-apex.com/, has developed an open source framework to handle customized tabular forms. Though it is very good it does not allow for complete access. Marcie Young did a presentation at ODTUG 2008 which outlined a very similar method, this example is taking it a step further. A working example is available here: http://apex.oracle.com/pls/otn/f?p=20195:200
The process below will not only build a customized tabular form, but also handle the errors etc.
Here’s an overview of the overall methodology
- Create 2 collections. One will handle data: DATA_COLLECTION and one will handle the errors: ERROR_COLLECTION.
- The DATA_COLLECTION will be loaded on the first viewing of the page and will only be refreshed from the database when the changes have been sent to the database.
- The ERROR_COLLECTION will contain errors specific for the corresponding entry in the DATA_COLLECTION. We could keep this in the same collection, but I like to keep them separate. It makes things easier if we need to add or remove columns.
- In the ERROR_COLLECTION I keep column 50 reserved for the row error. An example of when you’d need a row error is when you have a start and end date and the end date is before the start date.
- This application will allow users to modify the emp.ename and emp.salary fields
- In the data collection I keep column 1 reserved for the sequence id (seq_id). Note though I won’t use it in this example, it has come in handy (especially when hiding/delete rows in the front end then submitting the page)
Step 1: Create a PL/SQL Process On Load Before Header called Create Collection
DECLARE BEGIN IF NVL (:p200_reload_flag, 'N') = 'N' THEN -- IF error collection exists, delete IF apex_collection.collection_exists (p_collection_name => 'ERROR_COLLECTION') THEN apex_collection.delete_collection (p_collection_name => 'ERROR_COLLECTION'); END IF; -- Create New Collection apex_collection.create_or_truncate_collection ('DATA_COLLECTION'); FOR rec IN (SELECT e.empno, e.ename, e.sal FROM emp e ORDER BY e.ename) LOOP apex_collection.add_member (p_collection_name => 'DATA_COLLECTION', p_generate_md5 => 'NO', p_c002 => rec.empno, p_c003 => rec.ename, p_c004 => TO_CHAR (rec.sal), -- Remember the collection is only text p_c049 => 'Y', -- Modifiable Flag p_c050 => 'U' -- SQL Action (Insert, Update, Delete) ); END LOOP; -- END IF; -- Create Extra rows (if we wanted to add a new employee FOR i IN 1 .. NVL (:p200_num_extra_rows, 0) LOOP apex_collection.add_member (p_collection_name => 'DATA_COLLECTION', p_generate_md5 => 'NO', p_c002 => -1, -- use negative numbers for new employees p_c049 => 'Y', p_c050 => 'I' ); END LOOP; -- Insert seq_id FOR rec IN (SELECT ac.seq_id FROM apex_collections ac WHERE ac.collection_name = 'DATA_COLLECTION') LOOP apex_collection.update_member_attribute (p_collection_name => 'DATA_COLLECTION', p_seq => rec.seq_id, p_attr_number => 1, p_attr_value => rec.seq_id ); END LOOP; END;
Step 2: Create a Report / SQL Report region for our custom tabular form called Employee Data
SELECT -- Notice how I'm keeping the idx value the same as the column value in the collection. This helps to keep things organized -- I also apply an id to each entry -- I append the error value to the empname and sal -- The Seq_id. Usefull when hiding rows (for delete) and then submitting from apex_item.hidden(1,x.seq_id, null, x.seq_id || '_seq_id') || -- The Primary Key of the column apex_item.hidden(2, x.empno, null, x.seq_id || '_empno_id') || x.empno empno, -- Employee Name apex_item.text(3,x.empname,null, null, null, x.seq_id || '_empname_id') || err.empname employee_name, -- Employee Salary apex_item.text(4,x.sal, null, null, null, x.seq_id || '_sal_id') || err.sal || -- Store the sql action type as well. apex_item.hidden(50,x.sql_action_typ, null, x.seq_id || '_sql_action_typ_id') sal, -- Last but not least the row error err.row_error FROM (SELECT ac.c001 seq_id, ac.c002 empno, ac.c003 empname, ac.c004 sal, ac.c049 modifiable_flag, ac.c050 sql_action_typ FROM apex_collections ac WHERE ac.collection_name = 'DATA_COLLECTION' ORDER BY ac.seq_id) x, -- Error Collection (SELECT ac.seq_id seq_id, ac.c002 empno, ac.c003 empname, ac.c004 sal, ac.c050 row_error -- Useful when individual data is correct, however the row of data is not. Ex: start/end dates FROM apex_collections ac WHERE ac.collection_name = 'ERROR_COLLECTION' ORDER BY ac.seq_id) err WHERE x.seq_id = err.seq_id(+)
Step 3: Add Region items and buttons
All items/buttons should be added to the report region
ADD, submit page. Branch to &APP_PAGE_ID.
SUBMIT, submit page. Branch to 201
Note: Page 201 is a simple sql report for
Create Hidden and Protected Items:
- Source value or expression: N
- Comment: Used to determine if the error column should be displayed
- Source value or expression: 1
- Comment: Number of extra rows to add to the tabular form
- Comment: If Y then we won’t refresh the collection with database values
Computations (After Submit)
Condition: Request = ADD
Condition: Request != ADD
Step 4: Store Collection
After submit, this will store the data from the form into the collection. No data validation is performed at this point
Process: Store Collection
Type: PL/SQL Anonymous Block
Processing Point: On Submit: Before Computation and Validations
DECLARE BEGIN FOR i IN 1 .. apex_application.g_f01.COUNT LOOP apex_collection.update_member (p_collection_name => 'DATA_COLLECTION', -- I know some of you are still wondering why were are still wondering why I stored the seq_id as a collection attribute. This is why. If you had hidden the row (i.e. let the user "delete" it) then it would not show up on this and your collection synchronization wouldn't be correct. p_seq => apex_application.g_f01 (i), -- Sequence ID p_c001 => apex_application.g_f01 (i), -- Sequence ID p_c002 => apex_application.g_f02 (i), -- Empno p_c003 => apex_application.g_f03 (i), -- Empname p_c004 => apex_application.g_f04 (i), -- Sal p_c049 => 'Y', -- Modifiable Flag p_c050 => UPPER(apex_application.g_f50 (i)) ); END LOOP; END;
Step 5: Validation
Type: Page Level Validation
Type: PL/SQL - Function returning Error Text
Name: Validate Collection
Condition: When Button Pressed - SUBMIT
DECLARE v_err_msg VARCHAR2 (255); BEGIN -- IF error collection exists, truncate. Else Create IF apex_collection.collection_exists (p_collection_name => 'ERROR_COLLECTION') THEN apex_collection.truncate_collection (p_collection_name => 'ERROR_COLLECTION'); ELSE -- Create Error Collection apex_collection.create_or_truncate_collection ('ERROR_COLLECTION'); END IF; -- Basic Check. Make sure the emp name is more than 5 chars long FOR x IN (SELECT ac.c003 empname, ac.c004 sal, ac.seq_id FROM apex_collections ac WHERE ac.collection_name = 'DATA_COLLECTION') LOOP -- Always add a blank error apex_collection.add_member (p_collection_name => 'ERROR_COLLECTION'); IF LENGTH (x.empname) < 5 THEN apex_collection.update_member (p_collection_name => 'ERROR_COLLECTION', p_seq => x.seq_id, p_c003 => ' Name must be 5 Chars' ); v_err_msg := 'Error Occured'; END IF; -- Add a "row level" check for demo purposes IF LENGTH (x.empname) = LENGTH (x.sal) THEN apex_collection.update_member (p_collection_name => 'ERROR_COLLECTION', p_seq => x.seq_id, p_c050 => ' Row Level Error' ); apex_util.set_session_state (p_name => 'P200_DISPLAY_ROW_ERROR_FLAG', p_value => 'Y' ); v_err_msg := 'Error Occured'; END IF; END LOOP; RETURN v_err_msg; END;
Step 6: Finishing it off
As you notice there’s a column called: row_error. Set the condition where item: P200_DISPLAY_ROW_ERROR_FLAG = Y.