How To Fix OO037 - Chose either 'Instance event' or 'Class event'

SAP Error Message - Details

• Message type: E = Error

• Message class: OO - Class Builder/API

• Message number: 037

• Message text: Chose either 'Instance event' or 'Class event'

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message OO037 - Chose either 'Instance event' or 'Class event' ?

  The SAP error message OO037, which states "Choose either 'Instance event' or 'Class event'," typically occurs in the context of Object-Oriented Programming in ABAP, particularly when working with events in classes and interfaces.
  Cause:
  This error arises when you are trying to define an event in a class or interface but have not specified whether it is an instance event or a class event. In ABAP, events can be categorized into two types:
  
  Instance Events: These are events that are triggered for a specific instance of a class. They are defined using the EVENTS keyword in the class definition.
  Class Events: These are events that are triggered at the class level, not tied to a specific instance. They are defined using the CLASS EVENTS keyword.
  
  If you attempt to define an event without clearly indicating which type it is, the system will raise the OO037 error.
  Solution:
  To resolve this error, you need to explicitly specify whether you are defining an instance event or a class event. Here’s how you can do that:
  
  
  For Instance Events:
  
  Use the EVENTS keyword in the class definition.
  CLASS my_class DEFINITION.
  EVENTS my_instance_event.
  ENDCLASS.
  
  
  
  
  For Class Events:
  
  Use the CLASS EVENTS keyword in the class definition.
  CLASS my_class DEFINITION.
  CLASS EVENTS my_class_event.
  ENDCLASS.
  
  
  
  
  Related Information:
  
  Event Handling: When you define events, you also need to implement event handling methods that respond to these events. Make sure to implement the necessary methods to handle the events you define.
  Documentation: Refer to the SAP documentation on ABAP Object-Oriented Programming for more details on events, their types, and how to implement them correctly.
  Debugging: If you continue to face issues, check the surrounding code for any syntax errors or misconfigurations that might be causing the problem.
  
  By ensuring that you clearly define the type of event you are working with, you should be able to resolve the OO037 error effectively.