A Screen belongs to a Dialog and is considered as a list of fields.
These fields can be grouped into categories (top, bottom, repetitive). The processing is executed category by category.
The Presentation and Display default options defined in the Dialog Definition may be modified at the Screen level.
These presentation options can be changed in each call of Data Element on the Screen.
These Data Elements allow to build the Screen layout and determine the processing of the Screen data.
The processing of data external to the Screen is determined by the call of Segments and, for each of them, by the specification of its physical characteristics (type of organization...) and type of use (read, update...).
The development of a Dialog/Screen thus described is independent from the hardware/software configuration in use. This allows the online application generated to be portable.
All the procedures associated with a given Screen are generated in a single program which processes this Screen only.
This program is generated in COBOL and is automatically adapted to the hardware and TP monitor in use. It is contingent upon the type of Cobol to generate value of at the Dialog or Screen Definition.
The generated online program allows for man/machine exchanges in a pseudo-conversational mode in such a way as to optimize computer usage without penalizing the user.
For explanations on the generated Screen, refer to the On-Line Systems Development manual which you can find at the following URL:
http://www-1.ibm.com/support/docview.wss?rs=37&context=SSEP67&uid=swg27005478