Technical Corner

A: Response by Indrek Sooneste at HTMLDB forum

There are some tricks that can be used to validate detail form. At first take a look to your detail form, it is just a report. And updates are made using values in HTMLDB_APPLICATION.G_Fxx (where xx some number start at 01).

Example:
I made a master/detail form on demo_order and demo_order_items tables.
The select behind in detail form is

select "ORDER_ITEM_ID",
       "ORDER_ID",
       "PRODUCT_ID",
       "UNIT_PRICE",
       "QUANTITY"
  from "#OWNER#"."DEMO_ORDER_ITEMS"
  where "ORDER_ID" = :P5_ORDER_ID

So I created page level validation that checks if unit_price is empty and returns error message.

begin
FOR i IN 1.. HTMLDB_APPLICATION.G_F05.COUNT LOOP
  if HTMLDB_APPLICATION.G_F05(i) is null then
    return 'Unit Price cann''t be empti';
  end if;
END LOOP;
return null;
end;

To figure out what is the right number for G_Fxx check the HTML source. The error message is displayed inline in notification.

When you want to show error message inline with filed then you have to rebuild your detail form and use collections.