ARTICLE
Screen Flow and Screen Sequences
Screen Flow
Screens are called either through
transaction codes or using the
statement CALL SCREEN . During the call,
the event PBO is triggered and its event
block is processed in the screen flow
logic . Afterwards, the screen of the dynpro
(dynamic program) is displayed in the current or in a new
pop-up level (in the case of modal
dialog boxes). After a user action in the user interface of this window,
the event PAI (or
POH or POV
) is triggered and its event block is processed in the screen flow
logic. In the event blocks of the screen flow logic, dialog modules of
the appropriate ABAP program are called. When PAI processing is
closed, the next screen of the current
dynpro (dynamic program) is called.
Screen Sequence
Each screen has a next screen. In particular, a screen can also have
its own special next screen. The next screen is either statically
predefined ot it is set in the ABAP program using the statements
SET SCREEN or
LEAVE TO SCREEN . In this way, a screen is automatically part
of a screen sequence. Each next screen always belongs to a single pop-up
level and is executed in a single window. The number of the current
screen can be taken from the system field sy-dynnr .
The flow of a screen sequence is determined by the respective next
screen in the dynpro (dynamic program) concerned. During processing, a
screen always has a next screen. At the beginning of processing, this is
statically predefined, but it can be overwritten in the program. The
first screen of a screen sequence is the initial screen. A screen
sequence is ended by calling the next screen with the screen number 0.
If a screen sequence is embedded in another, the calling screen sequence
is continued after completion of a screen sequence. If the screen
sequence is not embedded, the current program is ended.
Documentation extract taken from SAP system, � Copyright SAP AG. All rights reserved