Module 8: Selection Screens & Reports

Selection screens are used to collect user input before executing ABAP reports.
Reports form the backbone of classic ABAP applications and are still widely used in productive systems.

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1. PARAMETERS & SELECT-OPTIONS

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1.1 PARAMETERS

PARAMETERS is used to define single-value input fields.

PARAMETERS p_carrid TYPE spfli-carrid.

With default value:

PARAMETERS p_year TYPE i DEFAULT 2025.

With mandatory input:

PARAMETERS p_name TYPE string OBLIGATORY.

Modern Recommendation

Use meaningful parameter names and restrict data types using DDIC references wherever possible.

1.2 SELECT-OPTIONS

SELECT-OPTIONS allows range-based input (single values, ranges, exclusions).

SELECT-OPTIONS s_carrid FOR spfli-carrid.

Internally, a select-option creates a structure with:

• SIGN

• OPTION

• LOW

• HIGH

When to Use SELECT-OPTIONS

Use SELECT-OPTIONS when:

• Multiple values are required

• Ranges are required

• Exclusions are required

2. Selection-Screen Events

Selection screens are event-driven, just like ABAP programs.

2.1 INITIALIZATION

Executed when the selection screen is first displayed.

INITIALIZATION.
  p_year = sy-datum+0(4).

2.2 AT SELECTION-SCREEN

Triggered during input validation.

AT SELECTION-SCREEN.
  IF p_year < 2000.
    MESSAGE 'Year must be >= 2000' TYPE 'E'.
  ENDIF.

2.3 AT SELECTION-SCREEN ON <field>*

Triggered for a specific field.

AT SELECTION-SCREEN ON p_year.
  IF p_year > sy-datum+0(4).
    MESSAGE 'Future year not allowed' TYPE 'E'.
  ENDIF.

Validation Rule

Always validate user input at selection-screen level, not inside business logic.

3. Dynamic Selection Screen Modification

Dynamic modification allows enabling, disabling, or hiding fields at runtime.

3.1 Using AT SELECTION-SCREEN OUTPUT

AT SELECTION-SCREEN OUTPUT.
  LOOP AT SCREEN.
    IF screen-name = 'P_YEAR'.
      screen-input = 0.
      MODIFY SCREEN.
    ENDIF.
  ENDLOOP.

Common Use Cases

• Hide fields based on user role

• Disable fields conditionally

• Change required input dynamically

Legacy but Still Relevant

Dynamic screen modification uses classic techniques and is still valid in 7.5, but should be kept simple and minimal.

4. Reports in ABAP

4.1 Classical Reports

Classical reports display output using WRITE.

WRITE: / 'Flight Data Report'.

Characteristics

• List-based output

• Minimal interaction

• Legacy style

Legacy Report Type

Classical reports should not be used for new developments.

4.2 Interactive Reports

Interactive reports respond to user actions like clicking or selecting.

AT LINE-SELECTION.
  WRITE 'Line selected'.

AT USER-COMMAND.
  CASE sy-ucomm.
    WHEN 'DETAIL'.
      WRITE 'Details requested'.
  ENDCASE.

Characteristics

• Multiple list levels

• Basic interactivity

• Heavy use of system fields

Interview Reality

Interactive reports are frequently asked in interviews due to their legacy importance.

5. Modern Reporting Recommendation (7.5+)

Modern Best Practice

For new developments, prefer:

• ALV (SALV / OO ALV)

• CDS-based reporting

• Fiori / UI5 frontends

6. Classical vs Interactive Reports

Aspect	Classical	Interactive
User Interaction	No	Limited
Events	Few	Many
Output	Simple list	Drill-down
Usage Today	Rare	Maintenance only

7. Common Beginner Mistakes

Avoid These

• Writing business logic in report events

• Overusing global variables

• Poor input validation

• Using WRITE instead of ALV

• Complex dynamic screen logic

8. Summary

• PARAMETERS → single input

• SELECT-OPTIONS → ranges and multiple values

• Selection screens are event-driven

• Dynamic screen modification is possible

• Classical & Interactive reports are legacy

• Modern ABAP prefers ALV and CDS-based reporting

9. Practice Exercises

-Create a report with PARAMETERS and SELECT-OPTIONS.

• Validate input using selection-screen events.

• Disable a field dynamically.

• Convert a classical report into ALV.

10. What’s Next?

➡️ Module 9: ABAP Debugging & Runtime Analysis

Learning Tip

Understanding selection screens is crucial for maintaining legacy reports and passing interviews.