User's Guide

In the second
method we will look at a way to define a variable that allows someone to pick from a
list of values or allows them to enter any value.
Part A (restricting the values that a variable can take using an enum)
The following configuration is what we want to end up with. We will look at what it contains line
by line and then look at how the variable can be used:
enum _my_location_codes
_my_location_codes = { "Not Valid", "AAA000", "AAA001", "AAA002", "AAA003" }
init _my_location_codes = "Not Valid"
_my_location_codes visible_if TRUE
_my_location_codes help_text "Choose a location code”
The first line defines the variable _my_location_codes to be an enum. That means that it can only
hold a value from the enumerated values assigned to it. It is not possible to set this variable to any
other value.
The second line assigns a list of values to the variable. A variable doesn’t have to be an enum to
give it a list of potential values like this, more on that in the next part of this example.
The third line gives the variable an initial value. Since this variable is an enum it should only be
assigned a value from the list of allowed values. Note the use of
init before the variable - the
init keyword is only required if you want the user to be allowed to change this value via the
additional button on the basic tab in itool. Without the
init keyword the user would not be
allowed to change the value.
The last line sets the variable so it can be seen via the additional button on the basic tab in
itool. If you did not want to allow the user to see this variable you must use
FALSE instead of
TRUE.
You should be aware that enums behave differently than other variables on the additional button
on the basic tab in itool. You cannot directly enter a value into an enum field, instead press
Enter where the help text is. When you do this you will be presented a list of values to choose
from. That is how to change the value for an enum.
The end result of this is to present to the user a field that they can change but can only select one of
a predefined set of values. The question you may be asking is why you would do this. In this case
the value of the
_my_location_codes variable could control networking information. If there were
one location code for each subnet you have HP-UX systems on, you could choose the appropriate
location code to supply information such as routing and other networking information common to
that subnet. This would require additional configurations that tested the value of
_my_location_codes and set up networking information accordingly.
You may have noticed that
_my_location_codes contained “Not Valid” as one of its possible
values. There is a good reason for this - in this case we want to force the person doing the
installation to set this value. If there is an initial value that you know is not valid, you can create
some configuration like:
( _my_location_codes == "Not Valid" ) {
error+="You have not selected a location code."
} else {
note+="The location code selected was " + ${_my_location_codes}
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