Modifying a DataWindow object
During execution, you can modify the appearance and behavior
of a DataWindow object by doing one of the following:
-
Changing the values of its
properties -
Adding or deleting controls from the DataWindow
object
Changing property values
You can use the Modify method or a property expression to
set property values. This lets you change settings that you ordinarily
specify during development in the DataWindow painter.
Before changing a property, you might want to get the current
value and save it in a variable so that you can restore the original
value later. To obtain information about the current properties
of a DataWindow object or a control in a DataWindow object, use
the Describe method or a property expression.
Using expressions in property values
With some DataWindow properties, you can assign a value through
an expression that the DataWindow evaluates during execution, instead
of having to assign a value directly. For example, the
following statement displays a salary in red if it is less than $12,000,
and in black otherwise:
1 |
dw_1.Modify("salary.Color & |
1 |
= '0 ~t if(salary <12000,255,0)' ") |
For more information
The syntax is different for expressions in
code versus expressions specified in the DataWindow painter. For
the correct syntax and information about which properties can be
assigned expressions, see the DataWindow Reference.
For more information about property expressions
and DataWindow object properties and examples of using Describe
and Modify methods, see the DataWindow Reference.
Adding and deleting controls within the DataWindow
object
You can also use the Modify method to:
-
Create new objects in a DataWindow
objectThis lets you add DataWindow controls (such as text, bitmaps,
and graphic controls) dynamically to the DataWindow object.For how to get a good idea of the correct
Create syntax, see “Specifying the DataWindow
object syntax”. -
Destroy controls in a DataWindow
objectThis lets you dynamically remove controls you no longer need.
PowerBuilder tool for easier coding of DataWindow
syntax
PowerBuilder only
Included with PowerBuilder is DW Syntax, a tool that makes
it easy to build the correct syntax for property expressions, Describe, Modify,
and SyntaxFromSQL statements. You click buttons to specify which properties
of a DataWindow you want to use, and DW Syntax automatically builds
the appropriate syntax, which you can copy and paste into your application
code.
See Using DWSyntax for
more information.
Viewing DataWindow object properties in PowerBuilder
PowerBuilder only
You can use the PowerBuilder Browser to get a list of DataWindow
properties: on the DataWindow tab, select a DataWindow object in
the left pane and Properties in the right pane. To see the properties
for a control in a DataWindow object, double-click the DataWindow
object name, then select the control.