Defining structures
Although you define object-level structures in the painter
for a specific object and global structures in the Structure painter,
in both cases you define the structure in a Structure view. The
following sections describe each of the steps you take to define
a new structure:
- Open a Structure
view. - For object-level structures, name the structure.
- Define the variables that make up the structure.
- Save the structure.
Opening a Structure view
How you open the Structure view depends on whether you are
defining an object-level structure or a global structure.
To define an object-level structure:
-
Open the object for which you want to declare
the structure.You can declare structures for windows, menus, user objects,
or applications. -
Select Insert>Structure from the menu
bar.A Structure view opens.
To define a global structure:
-
Select Structure from the Objects tab in
the New dialog box.The Structure painter opens. It has one view, the Structure
view. In the Structure painter, there is no Structure Name textbox
in the Structure view.
Naming the structure
If you are defining an object-level structure, you name it
in the Structure Name box in the Structure view. If you are defining
a global structure, you name it when you save the structure.
Structure names can have up to 40 characters. For information
about valid characters, see the PowerScript Reference
.
You might want to adopt a naming convention for structures
so that you can recognize them easily. For example, you could preface
all global structure names with s_ and all object-level
structure names with str_.
Defining the variables
To define the variables that compose the structure:
-
Enter the data type of a variable that
you want to include in the structure.The default for the first variable is string; the default
for subsequent variables is the data type of the previous variable.
You can specify any PowerBuilder data type, including the standard
data types, such as integer and string, as well as objects and controls,
such as window or MultiLineEdit.You can also specify any object types that you have defined.
For example, if you are using a window named w_calculator
that you have defined and want the structure to include the window,
type w_calculator as
the data type. (You cannot select w_calculator from the
list, since the list only shows built-in data types.)
A structure as a variable A variable in a structure can itself be a structure. Specify
the structure’s name as the variable’s data type. Specifying decimal places If you select decimal as the data type, the default number
of decimal places is 2. You can also select decimal{2} or
decimal{4} to specify 2 or 4 decimal places explicitly. - Enter the name of the variable.
- Repeat until you have entered all the variables.
Saving the structure
How you save the structure depends on whether it is an object-level
structure or a global structure.
The names of object-level structures are added to the Structure
List view and display in the titlebar of the Structure view as soon
as you tab off the Structure Name box. As you add variables to the
structure, the changes are saved automatically. When you save the
object that contains the structure, the structure is saved as part
of the object in the library in which the object resides.
Comments and object-level structures You cannot enter comments for an object-level structure, because
it is not a PowerBuilder object.
To name and save a global structure:
-
Select File>Save from the menu
bar.or
Close the Structure painter.
The Save Structure dialog box displays.
- Name the structure.
- (Optional) Add comments to describe your structure.
- Choose the library to save the structure in.
-
Click OK.
PowerBuilder stores the structure in the specified library.
You can view the structure as an independent entry in the Library
painter.