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70 Connie’s Convenience Store Establishing Human Interaction Responsiblities
Logon window
Establish responsibilities: “what I know.”
#57. “Establish Window establishing responsibilities /
or Report Attributes” Strategy what I know (model components)
• For windows or reports, include: search fields, data entry fields, or both.
For the logon window, you need these fields:
– cashier number
– cashier password
– register number.
Establish responsibilities: “who I know.”
#79. “Establish Window or Report establishing responsibilities /
Object Connections” Strategy who I know (model components)
• For a window or report, include an object connection (expressed as an attribute) to: the
contents of the window, the objects it knows directly, to get the content it needs to do its
job (note that a window can use those objects to get to other objects, indirectly).
Here the objects a logon window needs to know include:
– store (a collection of cashiers, with the ability to search for a cashier,
given a cashier number)
– cashier.
One could model this “who I know” aspect with object connections. Yet object connections
that span across object-model components are usually shown textually (so that
they are easier to read and understand).
Establish responsibilities: “what I do.”
Here’s how.
For a window, the “what I do” are those the window-specific menu actions for that
window.
In addition, every window object knows how to display itself. And every window
class knows how to create (and initialize) a new object in that class.
Here, all you need to add is:
– logon.
Add the logon window and its responsibilities to the object model (Figure 1–45):