‎2007 May 07 6:18 AM
Hi,
What are the events in module pool programming????and what are the statements used for Mpp(i mean like fields:,chain...endchain) and what are the use of these statements????
‎2007 May 07 6:20 AM
PBO event
This event is triggered before the screen is displayed. The processing of screen before the display of screen is done in this event. For example, filling in default values in the screen fields.
PAI event
This event is responsible for processing of screen after the user enters the data and clicks the pushbutton. The processing of screen can include displaying another screen, or just displaying list or quitting the transaction itself and many more things. Usually it is displaying another screen. These operations can be carried out in the PAI event. OKCODE plays an important role in this operation.
POV event
Process on value request is triggered when the user clicks F4 key. You can handle this event when the user presses F4 key by writing code for the same in module pool program. Normally when the user presses F4, list of possible values is displayed. The standard list produced by system is adequate for applications you develop yourself. However, you can also have the option of setting up your own documentation and lists of possible values that are more detailed.
POH event
Normally when the user places the cursor on the field and presses F1 function key, the system displays its own Help for that particular field. You can add your own functionality to the Help button by writing code for the same in the POH event.
‎2007 May 07 6:21 AM
‎2007 May 07 6:22 AM
check this
ABAP Statements of the Screen Flow Logic
Screen Keywords:
PROCESS Defines the processing event
( BEFORE OUTPUT / AFTER INPUT)
FIELD Specifies the field to which the
processing refers.
MODULE Specifies the processing module
SELECT Checks input against a table
VALUES Defines permitted input values
(can only be used with FIELD)
CHAIN Starts a processing chain
ENDCHAIN Ends a chain
LOOP Starts block processing
ENDLOOP Ends block processing
Additional Processing Control Specifications:
ON INPUT Process only on input
(where field contents are not initial)
ON CHAIN-INPUT Process only on input in a chain
ON REQUEST Process only on request (when
user enters a value on the screen)
ON CHAIN-REQUEST Process only on request in a chain
ON -INPUT Process only on '' input
AT EXIT-COMMAND Process only on command entry 'E'
to cancel all entries
AT CURSOR-SELECTION Process only after cursor selection
General Rules:
- Each statement concludes with a period.
- You can combine FIELD with MODULE
and SELECT.
- You can only use VALUES together with field
assignment (FIELD).
- You can only use ON ... with field assignments.
Application Help
Screens
Processing Screens
Regards
Prabhu
‎2007 May 07 6:24 AM
Hi
Check if the info is helpful
The screen flow logic is divided into four components:
1.Process Before Output (PBO) event:
which is processed before the screen is displayed
2.Process After Input (PAI) event:
Which is processed after a user action on the screen
3.Process on help request (POH)
which is processed when F1 is pressed
4.Process on value request (POV)
Which is processed when F4 is pressed