Suppose you want to give an option to user to select only 5 check boxes from given any number of check boxes in an Oracle Form and if user selects more than 5 than give a message that you can not select more than 5.
For this follow these steps:
Create 10 check boxes in block with name like checkbox1, checkbox2, checkbox3 and so on.
Then write the When-Checkbox-Changed trigger at block level and put the following code in it:
declare
nlabel number := 1;
total_checked number := 0;
begin
while nlabel <= 10 loop
if checkbox_checked('block3.CHECKBOX'||nlabel) then
total_checked := total_checked + 1;
if total_checked > 5 then
message('more than 5 selected.');
copy('N', :System.Cursor_Item);
exit;
end if;
end if;
nlabel := nlabel + 1;
end loop;
raise form_trigger_failure;
end;
