4.2.1 Bug: Current values of child cascading LOVs are LOST.

Question

Hello, ApEx Team!
This bug affected 4.1.1 and 4.2.1 but with different behavior. It seems that someone was trying to fix it.
According to docs "whats new in 4.1" a value of refreshed child cascading lov is derived from default value settings of select list.
Please follow these steps to see the bug.l builder-work done for you here http://apex.oracle.com/pls/apex/f?p=14110:1
1.Create primary select list P1_SEL1.
  Display null value: Yes
  LOV definition:
    select 'aaa' name,'a' id
      from dual
     union all
    select 'bbb' name,'b' id
      from dual
     union all
    select 'ccc' name,'c' id
      from dual2.Create child select list P1_SEL2.
  Cascading LOV Parent Item: P1_SEL1
  Page Items to Submit: P1_SEL2 (I strongly believe that this item should be submitted automatically along with Parent Item)
  Display Null Value: Yes
  LOV definition:
    select 'aaa' name,'a' id
      from dual
     union all
    select 'bbb' name,'b' id
      from dual
     where :P1_SEL1 in ('b','c')
     union all
    select 'ccc' name,'c' id
      from dual
     where :P1_SEL1 in ('c')
  Default: return :P1_SEL2;
  Default Value Type: PL/SQL Function Body3.Run app. and manually change P1_SEL1 and P1_SEL2 to 'bbb'.
4.Manually change P1_SEL1 to 'ccc'.
h2.
In apex 4.1.1..
you see that P1_SEL2 is resetted to NULL automatically. The value of P1_SEL2 is LOST. Although I tell apex to submit P1_SEl2 value to set its session state, but the session state still remains NULL.
The session state of P1_SEL2 is always NULL and I have no idea how to set it as it is set in a browser at the moment of changing parent LOV P1_SEL1.
h2.
Now apex 4.2.1.
It seems this bug is fixed. Indeed it is NOT fixed.
To see this bug in 4.2.1 just...
5.Create a third child select list P1_SEL3 which depends on P1_SEL2.
  Cascading LOV Parent Item: P1_SEL2
  Page Items to Submit: P1_SEL3 (Again, I hope you will always submit current item automatically as you do for the parent item)
  Display Null Value: Yes
  LOV definition:
    select 'aaa' name,'a' id
      from dual
     union all
    select 'bbb' name,'b' id
      from dual
     where :P1_SEL2 in ('b','c')
     union all
    select 'ccc' name,'c' id
      from dual
     where :P1_SEL2 in ('c')
    Default: return :P1_SEL3;
    Default Value Type: PL/SQL Function Body6.Run app. again. Manually set P1_SEL1, P1_SEL2 and P1_SEL3 to 'bbb'.
7.Change P1_SEL1 to 'ccc' and see the bug:
1) P1_SEL2 is reset to NULL for just a short time and than restored to 'bbb'.
2) P2_SEL3 is reset to NULL. So the session state was NULL for this item at the moment of calculating default value. As a result the value of child cascading lov is LOST.
So this bug is still present in 4.2.1.
Can I hope to get workaround for this problem in 4.1 and 4.2?
Thank you,
Vladimir
Edited by: vgoncharov on 17.12.2012 19:37
Edited by: vgoncharov on 17.12.2012 22:45

Answer 1

Good to hear this is already being worked on.
When we tried to work around the "Automatic detection" bug - changing the "Application Language Derived From" to "Application Preference" or "Session" - we hit issue that some page processes were not firing in translated application.
See Page processes not firing in Translated applications
Jan