How to Implement Screen Exit for SAP Standard Transaction

Screen Exit for SAP Standard Transaction: SAP provides standard transactions to enter data into database. But a client may want to maintain some additional information in SAP other than what is provided. To make provisions for this, additional screens have to be provided and additional fields must be added into appropriate database table.

To pave way for this, SAP has provided the option for screen exits.

Usually, SAP provides the following:

1), An append structure in the database table with the new fields.

2), A sub screen area into the standard screen – where the programmer can attach his sub screen of his own program with the new fields.

3), A function group under which the new sub screen has to be created with the new fields.

4), Function exits to synchronize the PBO and PAI of the standard SAP program with the PBO and PAI of the sub screen – so that data can flow back and forth between the standard SAP program and the program written by the developer for the sub screen  These function modules also exist in the same function group under which the sub screen will have to be developed.

5),Finally, a linkage has to be done between the sub screen area of standard SAP screen with the custom sub screen constructed by the developer.

6), Typically, SAP provides an enhancement in which the developer can create an append structure, use the function exits to synchronize the PBO and PAI of the standard SAP program and the custom sub screen program, and make the necessary linking (as mentioned above in step 4. But, again, this is not a hard and fast rule. Linking in some case, is also done by configurations.) SAP also usually provides the name of the function group under which the sub screen has to be developed.

Necessary guidance about implementing a screen exit development is usually available in the Documentation section of the enhancement ( can be availed by transaction SMOD).

Screen Exit for SAP Standard Transaction

Pre-Requisites

The developer to work on screen exit should have essential knowledge on the following:

1), DDIC concepts, including the knowledge of append structure.
2), Concept of SAP Enhancements and implementing them using Projects.
3), Concept of function exits.
3), Knowledge on Module Pool – including sub screens, Tab strip controls etc.

Also See:What is Transactions in SAP?

Guidelines

A developer can follow the guidelines mentioned below to implement a screen exit to a standard SAP transaction, as and when required:

Find out the Required Enhancements

Go to SMOD. Press F4 in the Enhancement field. In the next popup window, click pushbutton ‘SAP Applications’. A list will appear that contains information on all the enhancements, categorized under functional areas. Developer must search for the enhancements relevant to his functional area of interest – for e.g., Purchasing, Asset Accounting, etc.

Note down the enhancements. Then, come to the initial screen of SMOD and view the documentation of each enhancement to find out which one is required for your development.

Utilize the Enhancement in a Project

After you have found one, do as directed in the documentation. Generally, the steps are as follows:

1), Create a project using CMOD including your enhancement.

2),Create the append structure with new fields.

3),Go to the desired function group and create a subscreen with the new fields. Write PBO and PAI for the subscreen, if required.

4), Use the function exits in the enhancement to link the PBO and PAI of the subscreen with that of the main SAP program supporting the SAP transaction.

5), Maintain necessary linkage between the subscreen area of standard SAP program with the custom subscreen developed along with the custom program name. This can be done in the project (developed by CMOD including the enhancement) or outside as a part of configuration.

6), Activate the project.

Test to ensure that required functionality are met.

Also See: What is Cross Company Code Transactions in SAP FICO?