TREE VIEW DEFAULT NODE CHECK IF ANY ONE CHECK

[Dilip]

hi all ,

i m trying to make such a tree view which specify some
folder structure for installation

i mean there is some folders mandatory. This is installation software.
is based upon user choice, what he will check only
those folders will be install not others.

A--|
|-A1
|-A2
|-A3
|-A4

B--|
|-B1
|-B2
|-B3
|-B4
C--|
|-C1
|-C2
|-C3
|-C4

suppose all 2's mean A2,B2,C2 are mandatory mean they should install
in theire respective field like A ,B , C installtion.

at start we are not showing any check mark with mandatory folder

but if user chek A1 then A2 should be automatic checked at that time
(bcoz its mandatory
)same concept
if user uncheck A1 then A2 unchecked bcoz he doesnt want to install
any part of folder A.

one more example when he check
B3 then B2 will automatic chek(mandatory folder) but since user
chechked
B3 so now
he cant unchek B2 untill he unchecks B3.

suppose he cheks B3 then B2 must cheked now he can check any number of
folder here.like B4 and B1 also but
conclusion is that if any node checked apart from mandatory node
then mandatory will be checked otherwise not

hope u got my problem .. can anyone suggest me some idea or code
for any help i would like to thanks in advance.