Selection Screen Processing
Selection screen processing packages the dynpro flow logic together with the sending of the selection screen. No dialog modules of the program are called. Instead, various selection screen events are triggered for which event blocks can be programmed. PBO processing triggers the event
. PAI processing triggers a variety of different events
. Selection screen processing of a displayed selection screen is ended only by selection of the following functions of the GUI status:
- Execute or Execute + Print
Triggers the selection screen events of PAI processing. After this, the event
START-OF-SELECTIONis triggered for standard selection screens called using
SUBMIT. For selection screens called using dialog transactions, the program is ended. A call in the program resumes the program after the statement
- Back, Exit, or Cancel
Triggers the event
AT SELECTION-SCREEN ON EXIT-COMMANDonly. After this, the program is ended for standard selection screens called using
SUBMITand dialog transactions. Otherwise,
sy-subrcis set to 4 and the program resumes after the statement
For all other user actions, the selection screen is called again automatically after selection screen processing is ended.
- The selection screen processor also encapsulates the processing of the
function codes assigned
to the control elements of the selection screen. The function code that triggers PAI processing is passed to the component
ucommof an interface work area
sscrfieldswith the type of the structure SSCRFIELDS. If an interface work area of this type is declared in a program using the statement
TABLES, the function code can be accessed. It is not advisable to access the system field
sy-ucomm, however, since it is not possible to guarantee that it has the same value as
sscrfields-ucommin all situations.
- Whether a program resumes depends on the function code in the UCOMM component of the
interface work area
SSCRFIELDS at the end of PAI processing. If this is declared using
TABLESand if this component is set to the value "ONLI" (for example, during processing of the standard selection screen of a program called using
SUBMIT) and this value is assigned to the function Execute, the event
START-OF-SELECTIONis raised after selection screen processing. Overwrites of the system field
sy-ucomm, however, are ignored.
- To avoid ending the program following the processing of a selection screen called using a dialog transaction, either the
dynpro must be called using
LEAVE TO SCREENor a new dynpro sequence called using
CALL SCREEN(during the processing of the selection screen). The statement
SET SCREENis not enough here.
- In selection screen processing, the statement LOOP AT SCREEN can be used to access the attributes of screen elements on the selection screen.