ABAP Keyword Documentation → ABAP - Reference → User Dialogs → Screens
Screen Flow and Screen Sequences
Other versions: 7.31 | 7.40 | 7.54
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.