If multiple checkbox is selected, value is not being displayed

[walkerist]

I have 2 check boxes and if it is both selected at the same time, it doesn't get executed

SELECTION-SCREEN BEGIN OF BLOCK chk1
                WITH FRAME TITLE text-008.
PARAMETERS: chk_morning AS CHECKBOX DEFAULT 'X',
            chk_evening AS CHECKBOX.
SELECTION-SCREEN END OF BLOCK chk1.

IF chk_morning = abap_true.
    WRITE / 'Morning'.
ELSEIF chk_evening = abap_true.
    WRITE / 'Evening'.
ELSE.
    WRITE / 'Morning and Evening'.
ENDIF.

When both the checkbox morning and evening is selected, the write statement 'Morning and Evening' is not being displayed. Any help is appreciated. Thank you

[Rajasekhar_Dina]

IF chk_morning = abap_true.
WRITE / 'Morning'.
ENDIF.


IF chk_evening = abap_true.
WRITE / 'Evening'.
ENDIF.


IF chk_morning = abap_true AND chk_evening = abap_true.
WRITE / 'Morning and Evening'.
ENDIF.

[Sandra_Rossi]

Please delete your duplicate answer. Thanks.

[anujawani2426]

Hi,

SELECTION-SCREEN BEGIN OF BLOCK chk1
                WITH FRAME TITLE text-008.
PARAMETERS: chk_morning AS CHECKBOX DEFAULT 'X',
            chk_evening AS CHECKBOX.
SELECTION-SCREEN END OF BLOCK chk1.

IF chk_morning = abap_true.
    WRITE / 'Morning'.
ELSEIF chk_evening = abap_true.
    WRITE / 'Evening'.
ELSEIF chk_morning = abap_true AND chk_evening = abap_true.

WRITE / 'Morning and Evening'.

ENDIF.

[raymond_giuseppi]

You have added a required logical expression, but you have not rearranged the order of these expressions, so no sorry.

[anujawani2426]

Hi raymond.giuseppi order of written statement will change the result ?. All three conditions needs to be done. We dont know which condition has the priority so in that case how can you say that last conditions which i have added should be first or should not be the last. Or you want to say something else.

please clarify.

[anujawani2426]

Hi raymond.giuseppi I am totally disagree with your statement

[anujawani2426]

Hi raymond.giuseppi

If you have right answer, and as per your opinion my answer is wrong then you can put your answer so will get know it.

[raymond_giuseppi]

In online or F1 documentation you can find 'The logical expressions, beginning with the IF statement, are checked from top to bottom and the statement block after the first real logical expression is executed. If none of the logical expressions are true, the statement block after the ELSE statement is executed.' so 'order of written statement will change the result' - so start from more restrictive criteria (here both boxes are checked) to less, the ELSE will be the last one

[anujawani2426]

Hi raymond.giuseppi

I got your point. Thanks

[matt]

As an exercise, run it in the debugger and see how it is executed.

[anujawani2426]

Matthew Billingham tried and got it. Thanks

[former_member9115]

Hi,

You can try this.

IF chk_mor = ABAP_TRUE and chk_eve is initial.
    WRITE / 'Morning'.
ELSEIF chk_eve = ABAP_TRUE and chk_mor is initial.
    WRITE / 'Evening'.
ELSE.
    WRITE / 'Morning and Evening'.
ENDIF.

[raymond_giuseppi]

What happen when no box is checked?

[matt]

If you're going to use abap_true (which is a good thing), don't use IS INITIAL instead of = abap_false.

[former_member9115]

matthew.billingham

Thanks you sir for your suggestion.
Just for my knowledge I want to know why IS INITIAL not preferable? (so in future i can improve my skill)

[Sandra_Rossi]

shital1111

A checkbox is like boolean true/false. Used more by developers worldwide. That's why.Technically speaking, it's the same (like also = ' ' or = space etc.)

[matt]

shital1111 It's consistency and readability. Why use two different approaches instead of a single approach? With IS INITIAL you are relying on the programmer who reads your code in knowing that IS INITIAL means "false". With abap_false it's right there in the words!

I suggest you work your way through this https://github.com/SAP/styleguides/blob/main/clean-abap/CleanABAP.md or getting the book mentioned here https://blogs.sap.com/2022/06/14/simplified-learning-of-clean-abap-and-clean-ui5/

[former_member9115]

Thank You sandra.rossi

Thank You matthew.billingham

[DominikTylczyn]

Hello walkerist

Look at your IF...ELSEIF...ELSE...ENDIF statement carefully and see how it's evaluated and executed if both checkboxes are set.

1. The IF statement is true as chk_morning = abap_true so the block is executed
2. ELSEIF is not evaluated as previous IF is true, the block is not exeucted.
3. ELSE is not executed as the first IF is true - see SAP Help on IF statement to understand why ELSE is not executed in this case. The SAP Help reads:

If none of the logical expressions are true, the statement block after the ELSE statement is executed.

In your case the first logical expression is true, hence ELSE is not executed.

Best regards

Dominik Tylczynski

[former_member794557]

Hi,

Try this one.

IF chk_morn = abap_true AND chk_even = abap_true.
WRITE / 'Morning and Evening'.
ELSEIF chk_morn = abap_true.
WRITE / 'Morning'.
ELSEIF chk_even = abap_true.
WRITE / 'Evening'.
ELSE.
WRITE / 'nothing selected'.
ENDIF.

[raymond_giuseppi]

This is a correct answer 🙂

[former_member794557]

Tq, Raymond

[DominikTylczyn]

That's actually quite a good question on IF ELSEIF ELSE logic.

[gabmarian]

When you evaluate condition with IF-ELSEIF you always start with the more specific case and then proceed.

Do a google search for the FizzBuzz programming problem.

[raymond_giuseppi]

In a IF control structure, only the first valid statement block will be executed. So adapt your checks and their order.