AT SELECTION-SCREEN

[Former Member]

what are the sub events takes place in AT SELECTION-SCREEN,and help me to know the purpose of that events

[Former Member]

Hi

AT SELECTION-SCREEN - selscreen_event

Syntax

...

| { ON {para|selcrit} }

| { ON END OF selcrit }

| { ON BLOCK block }

| { ON RADIOBUTTON GROUP radi }

| { }

| { ON {HELP-REQUEST|VALUE-REQUEST}

| FOR {para|selcrit-low|selcrit-high} }

| { ON EXIT-COMMAND }.

Alternatives:

1. ... OUTPUT

2. ... ON {para|selcrit}

3. ... ON END OF selcrit

4. ... ON BLOCK block

5. ... ON RADIOBUTTON GROUP radi

6. ... { }

7. ... ON {HELP-REQUEST|VALUE-REQUEST} FOR

{para|selcrit-low|selcrit-high} }

8. ... ON EXIT-COMMAND

Effect

These additions allow individual evaluation of specific elements of the selection screens of the program. The information as to which selection has triggered the event is contained in the system field sy-dynnr.

Alternative 1

... OUTPUT

Effect

This event is triggered at the screen event PBO of a selection screen. In the event block, the selection screen can be prepared through assignments to the data objects of parameters and selection criteria and through dynamic screen modifications.

Note

The assignments to input fields in the event block AT SELECTION-SCREEN OUTPUT always affect the selection screen and overwrite the user inputs from previous displays of the same selection screen. Assignments in the event blocks LOAD-OF-PROGRAM oder INITIALIZATION, on the other hand, only have an effect at first program start.

Alternative 2

... ON {para|selcrit}

Effect

This event is triggered at the screen event PAI of a selection screen if the content of the input field of a parameter para or a line of a selection criterion selcrit was passed to the ABAP program. In the event block, the user input can be checked. Sending a warning or an error message in the event block makes the fields para and selcrit ready for input again.

No parameter that is defined as a radio button can be specified. For this purpose, the addition ON RADIOBUTTON GROUP is provided.

Note

If a user action takes place in the dialog box for the multiple selection of a selection criterion selcrit, the entries of the selection table are passed to the program, line by line. For each line, the event AT SELECTION-SCREEN ON selcrit is triggered.

Alternative 3

... ON END OF selcrit

Effect

This event is triggered after the selection table selcrit has been fully passed to the program after a user action in the dialog box for the multiple selection has taken place. In the event block, the entire selection table can be checked.

Alternative 4

... ON BLOCK block

Effect

This event is triggered at the screen event PAI of a selection screen if all the input fields of a block block of the selection screen were passed to the ABAP program. In the event block, the user inputs can be checked. Sending a warning or an error message in the event block makes all the fields of the block block ready for input again.

Alternative 5

... ON RADIOBUTTON GROUP radi

Effect

This event is triggered at the screen event PAI of a selection screen if all the fields of a radio button group radi of the selection screen were passed to the ABAP program. In the event block, the user input can be checked. Sending a warning or error message in the event block makes all the radion buttons of the block radi ready for input again.

Note

The individual fields of a radio button group are not passed individually and do not trigger the event AT SELECTION-SCREEN ON par.

Alternative 6

... { }

Effect

The event AT SELECTION-SCREEN itself is triggered as the last event of selection screen processing if all the input values were passed to the program. In this event block, all the user inputs can be checked. Sending a warning or an error message in the event block makes all the screen fields ready for input once again.

Alternative 7

... ON { HELP-REQUEST | VALUE-REQUEST } FOR

{para|selcrit-low|selcrit-high} }

Effect

The two events ON HELP-REQUEST and ON VALUE-REQUEST are triggered at the screen events POH and POV of a selection screen if - for the input field of a parameter para or one of the input fields of a selection criterion selcrit - the field help F1 or the input help F4 was called. Other selection events are not triggered.

In the event blocks, a self-defined field or input field can be programmed, which overrides any helps possibly defined in the ABAP Dictionary.

Notes

These event blocks can only be implemented for fields of the selection screen that are defined in the same ABAP program and not in a possibly linked logical database.

With the events for the field and input help, no data is transported between the selection screen and the ABAP program. As with general screens, suitable function modules must be used for these. The parameters and selection criteria changed for the input help are transported to the selection screen.

Alternative 8

... ON EXIT-COMMAND

Effect

This event is triggered if the user has called one of the functions Back, Exit or Cancel. In the event block, possible clean-up actions can be executed.

Example

In these executable programs, a standard selection screen and a further selection screen are defined. In the event blocks AT SELECTION-SCREEN, the inputs in the selection screens can be specially handled using the name p_carrid and the screen number in sy-dynnr.

REPORT demo_at_selection_screen.

• Global data

DATA: sflight_tab TYPE TABLE OF sflight,

sflight_wa LIKE LINE OF sflight_tab.

• Selection screens

PARAMETERS p_carrid TYPE spfli-carrid.

SELECTION-SCREEN BEGIN OF SCREEN 500.

SELECT-OPTIONS s_conn FOR sflight_wa-connid.

DATA s_conn_wa LIKE LINE OF s_conn.

SELECTION-SCREEN END OF SCREEN 500.

• Handling selection screen events

AT SELECTION-SCREEN ON p_carrid.

IF p_carrid IS INITIAL.

MESSAGE 'Please enter a value' TYPE 'E'.

ENDIF.

AUTHORITY-CHECK OBJECT 'S_CARRID'

ID 'CARRID' FIELD p_carrid

ID 'ACTVT' FIELD '03'.

IF sy-subrc = 4.

MESSAGE 'No authorization for carrier' TYPE 'E'.

ELSEIF sy-subrc <> 0.

MESSAGE 'Error in authority check' TYPE 'A'.

ELSE.

IF sy-ucomm = 'ONLI'.

CALL SELECTION-SCREEN '0500'.

ENDIF.

ENDIF.

AT SELECTION-SCREEN.

IF sy-dynnr = '0500'.

IF s_conn IS INITIAL.

MESSAGE 'Please enter values' TYPE 'W'.

ELSE.

SELECT *

FROM sflight

INTO TABLE sflight_tab

WHERE carrid = p_carrid AND

connid IN s_conn.

IF sy-subrc <> 0.

MESSAGE 'No flights found' TYPE 'E'.

ENDIF.

ENDIF.

ENDIF.

• Main program

START-OF-SELECTION.

...

[Former Member]

Hi

1. at selection-screen on field

2. at selection-screen output

3. at selection-screen block

4. at selection-screen on value-request

5. at selection-screen on help-request

Selection-screens are special screen defined in ABAP.

- This ABAP at run time only controls the flow logic of Selection-screens. The PBO and PAI triggers the num of. selection-screens.

The basic form of the selection screen events is the AT SELECTION-SCREEN event. This event occurs after the runtime environment has passed all input data from the selection screen to the ABAP program. The other selection screen events allow programmers to modify the selection screen before it is sent and specifically check user input.

At Selection-screen OUTPUT is trigerred in PBO of selection-screen.

- This allows you to modify the Selection-screen, before it is displayed.

At Selection-screen On Field is triggered in PAI of selection-screens.

- The input fields can b checked,in the corresponding event block. If an error message occurs within this event block, the corresponding field is made ready for input again on the selection screen.

At Selection-screen On Block is trigerred in PAI event.

- You define a block by enclosing the declarations of the elements in the block between the statements SELECTION-SCREEN BEGIN OF BLOCK block - END OF BLOCK block. You can use this event block to check the consistency of the input fields in the block.

At Selection-screen On value request.

- This event is trigerred for F4 help.

At Selection-screen On help request .

- This event is triggered when the user clicks F1 for help on fileds.

[Former Member]

Initialization:This event triggers even before selection screen is displayed.

Adv:Using this event we can maintain authorizations and we can intialize default values in selection screen.

At selection screen: This event is for validations in selectionscreen.It triggers after user enters some data in selection screen.

Adv:If user enters invalid data the field gets enabled and all other fields get disabled.

[Former Member]

Hi,

AT SELECTION-SCREEN OUTPUT: To validate selection screen attributes.

AT SELECTION-SCREEN ON <selections screen field>:

AT SELECTION-SCREEN ON VALUE-REQUEST FOR <selections screen field>.

AT SELECTION-SCREEN ON HELP-REQUEST FOR <selections screen field>: for help on the slections creen field

Regards,

Sriram

[Former Member]

Hi,

At selection-screen output.

To change the screen attributes i,e look and feel of the scree.

At selection screen on <field>

To validate a particular field on the selection screen.

At selection screen on value request

To provide F4 functionality to any selectioon screen field.

At selection screen on hel[p request

To provide F1 help.

reward if helpful

Rgds

Umakanth