Modifying the crosstab’s properties during execution – PB Docs 2019

As with other DataWindow objects, you can modify the properties of
a crosstab during execution using the Modify method. Some changes
require the DataWindow control to dynamically rebuild the crosstab;
others do not. (If the original crosstab was static, it becomes a
dynamic crosstab when it is rebuilt.)

Changes that do not force a
rebuild

You can change the following properties without forcing the
DataWindow control to rebuild the crosstab:

Changes that force a
rebuild

If you change any other properties, the DataWindow control
rebuilds the structure of the crosstab when Modify is called. You should
combine all needed expressions into one Modify call so that the
DataWindow control has to rebuild the crosstab only once.

Default values for
properties

For computations derived from existing columns, the DataWindow
control by default uses the properties from the existing columns. For
completely new columns, properties (such as font, color, and so on)
default to the first column of the preexisting crosstab. Properties for
text in headers default to the properties of the first text control in
the preexisting crosstab’s first header line.

For more about the Modify method, see Dynamically Changing DataWindow
Objects. For details on the DataWindow object properties, see
DataWindow Object Properties in DataWindow Reference.