Using nested reports
When designing a DataWindow object for a report, you can choose
to nest other reports (which are also DataWindow objects) within
it. The basic steps for using nested reports in an application are
the same ones you follow for the other report types. There are,
however, some additional topics concerning nested reports that you
should know about.
Availability Composite and nested reports are not available in the Web
DataWindow.
To learn about designing nested reports, see
the DataWindow Builder User’s Guide
or
the PowerBuilder User’s Guide
.
Printing multiple updatable DataWindows on a page
An advantage of composite reports is that you can print multiple
reports on a page. A limitation of composite reports is that they
are not updatable, so you cannot directly
print
several updatable DataWindows on one page. However, there is an indirect
way
to do that, as follows.
You can use the GetChild method on named nested reports in
a composite report to get a reference to a nested report. After
getting the reference to the nested report, you can address the
nested report during execution like other DataWindows.
Using this technique, you can call the ShareData method to
share data between multiple updatable DataWindow controls and the
nested reports in your composite report. This allows you to print
multiple updatable DataWindows on a page through the composite report.
To print multiple DataWindows on a page using
a composite DataWindow:
-
Build a window or form that contains DataWindow
controls with the updatable DataWindow objects. -
Define a composite report that has reports corresponding
to each of the DataWindows in the window or form that you want to
print. Be sure to name each of the nested reports in the composite
report. Naming the nested report To use GetChild on a nested report, the nested report must
have a name. To name a nested report in the DataWindow painter,
double-click it in the workspace and enter a name in the Name box
on the General property page. -
Add the composite report to the window or form
(it can be hidden). -
In your application, do the following:
-
Retrieve data into the updatable
DataWindow controls. -
Use GetChild to get a reference to the nested
reports in the composite report. -
Use ShareData to share data between the updatable
DataWindow objects and the nested reports. -
When appropriate, print the composite report.
The report contains the information from the updatable DataWindow objects.
-
Retrieve data into the updatable
Re-retrieving data Each time you retrieve data into the composite report, all
references (handles) to nested reports become invalid, and data
sharing with the nested reports is terminated. Therefore, be sure
to call GetChild and ShareData each time after retrieving data.
Creating and destroying nested reports during execution
You can create and destroy nested reports in a DataWindow
object dynamically during execution using the same technique you
use to create and destroy other controls in a DataWindow object.
Creating nested reports To create a nested report, use the CREATE keyword with the
Modify method. Supply the appropriate values for the nested report’s
properties.
Viewing syntax for creating a nested report The easiest way to see the syntax for creating a nested report
dynamically is to export the syntax of an existing DataWindow object
that contains a nested report. The export file contains the syntax
you need.
For more information about exporting syntax
in the Library painter, see the PowerBuilder User’s
Guide
or the DataWindow Builder User’s
Guide
.
When creating a nested report, you need to re-retrieve data
to see the report. In a composite report, you can either retrieve
data for the whole report or use GetChild to get a reference to
the new nested report and retrieve its data directly. For nested
reports in other reports, you need to retrieve data for the base
report.
Destroying nested reports To destroy a nested report, use the DESTROY keyword with the
Modify method. The nested report disappears immediately.
For more about creating and destroying controls
in a DataWindow object or report, see Chapter 3, “Dynamically Changing DataWindow
Objects “.
For a list of properties of nested reports,
see the DataWindow Reference
.