Smalltalk and Object Orientation: an Introduction - Free

interface builder would be unable to create the user interface window (this is actually a common
mistake even for those used to the VisualWorks system).
Figure 27.11: Initializing an application model
The remainder of the method in Figure 27.11 can then initialize the appl ication specific aspects of
the subclass of ApplicationModel. In this case it initializes an instance variable called toDoList
and a value holder 15 on a string for an instance variable entry. Finally it constructs the selection list
displayed on the left hand side of Figure 27.12 and stores it in the todoTable instance variable.
Figure 27.12: The working interface
27.8 Resource Finder
The Resource Finder (also known as the Finder) is a navigation aid for developers. It is intended to help
developers to find, edit, delete and execute resources such as windows and menus. Figure 27.13
illustrates the VisualWorks Finder. The left hand selection windo w presents application classes, while
the right hand selection window indicates the resources defined for the selected application class. There
are various filter options which can be used to reduce the number of application classes displayed. The
filters can be accessed by selecting the classes sub-menu from the view menu.
Figure 27.13 illustrates the resources defined for the VisualLauncher class (the class which is
used to display the VisualWorks Launcher window). As can be seen from this example, an application
can have more than one window specification (in this case it has two: windowSpec - the default
window specification and aboutDialogSpec). If when one of these is selected the user selects the
15
We will come back to value holders later in this chapter.
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