Tightly Coupled Applications
Where interdependencies exist between the steps in a business process, and
where the application functions that support these steps must therefore
interact closely with one another, a single application is used. In this
case, the procedure manual is created as a help library, and execution is
handled as follows:
The application creates a help instance for the
help library in the normal manner, creates its own main window but does
not make this window visible.
The application's main window makes itself the
active window, and sends an HM_DISPLAY_HELP message to the main help window
to cause the initial help panel to be displayed.
Each step in the business is defined using hypertext
or hypergraphic links with reftype=inform. When such an item is
selected, it causes an HM_INFORM message to be posted to the application's
main window (the active window).
When the application's main window receives the
HM_INFORM message, it examines the message parameters to determine the required
action, then creates one or more additional display windows or dialog boxes
and makes these visible, allowing the user to complete the required step.
When the current step is complete, the user selects
an appropriate menu bar item or pushbutton, and returns to the procedure
manual.
Using this technique, the application's main window retains overall control
of the application, and can ensure coordination between steps and impose
a sequence of execution if this is required.
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