Prompting for retrieval criteria in a DataWindow object
You can define your DataWindow object so that it always prompts for
retrieval criteria just before it retrieves data. PowerBuilder allows
you to prompt for criteria when retrieving data for a DataWindow
control, but not for a DataStore object.
To prompt for retrieval criteria in a DataWindow object:
-
If the Column Specifications view is not
already displayed, select View>Column Specifications from
the menu bar.In the default layout for the DataWindow painter, the Column Specifications
view displays in a stacked pane under the Properties view. All columns
defined for the DataWindow object are listed in the view. -
Select the Prompt check box next to each column
for which you want to specify retrieval criteria at runtime.
When you specify prompting for criteria, PowerBuilder displays
the Specify Retrieval dialog box just before a retrieval is to be
done. (It is the last thing that happens before the SQLPreview event.)
Each column you selected in the Column Specification view
displays in the grid. Users can specify criteria here exactly as
in the grid in the Quick Select dialog box. Criteria specified here
are added to the WHERE clause for the SQL SELECT statement
defined for the DataWindow object.
Testing in PowerBuilder
You can test the prompting for criteria by retrieving data
in the Preview view of the DataWindow object.
Using edit styles
If a column uses a code table or the RadioButton, CheckBox,
or DropDownListBox edit style, an arrow displays in the column header
and users can select a value from a drop-down list when specifying
criteria:
If you do not want the drop-down list used for a column for
specifying retrieval criteria to display, select the Override Edit
check box on the General page of the column’s Properties
view.
Forcing the entry of criteria
If you have specified prompting for criteria for a column,
you can force the entry of criteria for the column by selecting
the Equality Required check box on the Behavior page of the column’s
Properties view. PowerBuilder underlines the column header in the
grid during prompting. Selection criteria for the specified column
must be entered, and the = operator
must be used.
For more information
The section “Using Quick Select” describes in detail how you and your
users can specify selection criteria in the grid.
The chapter on dynamic DataWindow objects in the DataWindow Programmers
Guide describes how to write code to allow users to specify retrieval
criteria at runtime.