This topic describes how to use output terminals with an
Invoke screen operation node.
You can use the Edit Terminals menu
selection to add, delete, or modify output terminals (
) for an Invoke screen operation node.
In addition to its one output terminal used in
the situation in which no screen is recognized, an Invoke screen
operation node can have one output terminal for each next screen that
can occur following the application screen associated with the Invoke
screen operation node (see Working with next screens).
Each output terminal represents the beginning of a flow
branch that will be taken if the application screen associated
with that output terminal occurs.
As a simple example, suppose you have the following situation:
- A flow contains three Invoke screen operation nodes: InvokeA,
InvokeB, and InvokeC.
- Each Invoke screen operation node invokes a screen operation (ScreenOpA,
ScreenOpB, or ScreenOpC).
- Each screen operation has been created to manage a particular
application screen (ScreenA, ScreenB, or ScreenC).
- ScreenOpA has, in its list of next screens, a screen description
that accurately describes the application screen ScreenB, and has
another that accurately describes ScreenC.
When InvokeA has been invoked to manage ScreenA and has returned
successfully, then you want the following to occur:
- If the next screen displayed by the application is ScreenB, then
you want the flow to branch to InvokeB.
- If the next screen displayed by the application is ScreenC, then
you want the flow to branch to InvokeC.
To implement this branching to ScreenB, or ScreenC, you would:
On the node InvokeA, add an output terminal for ScreenB, and
then create a connection from this output terminal to the input terminal
of InvokeB.
Also on InvokeA, add an output terminal for ScreenC,
and then create a connection from this output terminal to the input
terminal of InvokeC.
The order of output terminals on the Invoke screen operations node
is significant: the runtime code evaluates the output terminals in
the same order (top to bottom) in which the output terminals are displayed
on the node in the flow editor. Thus, continuing the previous example,
if the output terminal connected to InvokeB is first in sequence,
then the runtime code would check for the occurrence of ScreenB first,
before checking for the occurrence of ScreenC. (Normally you do not
care which application screen the runtime code checks for first.)
To add an output terminal, remove an output terminal, or change
the order in which an output terminal occurs in a sequence of output
terminals on a node:
On the flow editor canvas, select the screen operation node
whose output terminals you want to modify.
On the menu bar of the workbench, select .
The Node Properties window opens.
To add a new output terminal to the node:
- In the Available Messages list, select
the message that you want to add.
- Click Add.
- The message is added to the Reply Message list.
- Click Apply.
- When you click OK, a new output terminal
corresponding to the message that you added will be added to the node.
To remove an existing output terminal from the node:
- In the Reply Message list, select the message
that you want to remove.
- Click Delete.
- The message you selected is removed from the Reply
Message list.
- Click Apply.
- When you click OK, the output terminal
corresponding to the message that you removed is removed from the
node.
To change the order in which an output terminal occurs:
- In the Reply Message list, select the message
that you want to modify.
- Click Up or Down to
change the order in which the output terminal occurs.
- Click Apply.
- When you click OK, the order of the output
terminal corresponding to message that you moved up or down is changed
as you specified.
Click OK to close the Node Properties
window.