Change in Dynpro

Question

Hi Experts,
How do you know if there were changes on a dynpro?
That saves some system variable?  That saves some table?
For example
If I have a field with value  'X', delete it,  and put 'X' again, Sap detects whether there has been a change, although containing the same. Does anyone know why?
Thank you.
Edited by: Ivan R on Jun 1, 2010 1:50 PM
Edited by: Ivan R on Jun 1, 2010 1:50 PM

Answer 1

HI
                                                  The DYNPRO Concept
Screen Attributes. The function of the screen attributes is to indicate a screen type and associate the
screen object to the SAP system, such as the ABAP programs which are to be executed when at that
screen. It also describes the screen order within a transaction.
Fields. Fields are the main screen elements. Fields are defined in the ABAP dictionary or internally in
the programs. Field attributes establish relationships between the screen fields as well as define their
behavior when end users are executing the transaction.
Screen layout. This function establishes the layout of the graphic elements on the screen, such as input
fields, labels, icons, radio buttons, check boxes, and element groups.
Flow Logic. This is the main screen definition for controlling the flow logic of the screen, that is, how
it reacts to user inputs and calls associated ABAP modules and programs as defined using the ABAP
program editor.
The DYNPRO Concept
DYNPRO, or dynamic program, has been quite a common term in SAP naming conventions. A DYNPRO
refers to a screen together with its flow logic. Actually, DYNPROs should be considered synonymous with
screens as created by the screen painter.
A dynpro, or dynamic program, consists of a screen and all the associated processing logic.
It contains field definitions, screen layout, validation and processing logic, and so forth.
The processing logic means that the dynpro controls what has to be done before the screen is displayed
(process before output, or PBO) and what has to be done after the user finishes entering information (process
after input, or PAI).
The components in charge of controlling the user dialogs are the dynpros (dynamic programs). The
technology base for the R/3 applications is made up of the interrelation of the dynpro interpreters and the
ABAP language. For their tasks, both use the global image of the data environment of R/3, which is held on
the ABAP dictionary. The runtime environment of the R/3 applications consists of two processors: one for the
dynpros and the other for the ABAP language
Regards from Pakistan