Using graphs

Supported environment


Graphs are supported. Because you can print DataStores, PowerBuilder provides some events and functions for DataStores that pertain to the visual presentation of the data. However, graph functions such as CategoryCount, CategoryName, GetData, SeriesCount, and so forth depend on the visual graph control, which is not created for a DataStore. These functions return an error value or an empty string when used with DataStore objects.

It is common for developers to design DataWindow objects that include one or more graphs. When users need to quickly understand and analyze data, a bar, line, or pie graph can often be the most effective format to display.

To learn about designing graphs, see Working with Graphs in Users Guide.

Working with graphs in your code

The following sections describe how you can access (and optionally modify) a graph by addressing its properties in code at execution time. There are two kinds of graph properties:

  • Properties of the graph definition itself

    These properties are initially set in the DataWindow painter when you create a graph. They include a graph's type, title, axis labels, whether axes have major divisions, and so on. For 3D graphs, this includes the Render 3D property that uses transparency rather than overlays to enhance a graph's appearance and give it a more sophisticated look.

  • Properties of the data

    These properties are relevant only at execution time, when data has been loaded into the graph. They include the number of series in a graph (series are created at execution time), colors of bars or columns for a series, whether the series is an overlay, text that identifies the categories (categories are created at execution time), and so on.

Using graphs in other PowerBuilder controls

Although you will probably use graphs most often in DataWindow objects, you can also add graph controls to windows, and additional PowerScript functions and events are available for use with graph controls.

For more information, see the section called “Using graphs” in Application Techniques.