Defining Data Dictionary Properties for Non-Data Controls

VPME allows you to provide its Data Builder (data dictionary) functionality for form controls that are not data-bound (i.e., the control's ControlSource property is blank). This feature allows you to place a non-data-bound control on a form that can tap into most of the Data Builder field properties, integrity and permissions settings enjoyed by data-bound controls. For example, a non-data-bound control can have data dictionary-provided properties such as a label, default value, textual help, picklist help, validation rules and more.

A non-data-bound control can be used to gather information that you only need during some part of the processing of a form. A VPME non-data-bound control is like a memory variable on steroids. It stores a value entered by a user, but it has properties and methods plus VPME data dictionary settings.

VPM's special SVPMAPPLICATIONCONTROLS.DBF table in the SVPM database is the key to implementing this feature. You simply add a field to the SVPMAPPLICATIONCONTROLS table, set Data Builder properties for the field and use the field with the non-data-bound control. Here are the detailed steps:

1.   Data Builder: In the Data Builder, add a field to the SVPMAPPLICATIONCONTROLS table. Give the field an appropriate name. Make the field the appropriate type and width for the form control you have in mind.

2.   Data Builder: Set up the desired Data Builder properties and integrity for the new SVPMAPPLICATIONCONTROLS field.

3.   Form Designer: Add the appropriate control based on a control in the VPMCTRLS.VCX, DEVCTRLS.VCX or PROCTRLS.VCX class library to a form. The Name property of the control must be set to the field name you added to SVPMAPPLICATIONCONTROLS.

4.   Form Designer: Set the following properties of the control to link (not bind) the control to the new field (leave the ControlSource property blank):

·       cName_DDD = SVPM

·       cName_DDF = field name you added to SVPMAPPLICATIONCONTROLS

·       cName_DDTV = SVPMAPPLICATIONCONTROLS.DBF

That's it. The form control now has the field properties you give it through the Data Builder or Data Manager.

Tip: Note that the SVPMAPPLICATIONCONTROLS table is not added to the DE of the form. The use of the SVPMAPPLICATIONCONTROLS table and the adding of fields to it simply provides a way to define field-level functionality and assign that functionality to a control through the “cName” control properties.

Tip: After a user enters a valid value into the control on a form, you can use the contents of the control's Value property in code that lets you do whatever you need to do with that value while the form is active.

 

More:

Useful Form_ Class Properties