How To Fix FDT_WD_EXPRESSION020 - Expression &1 is not a constant

SAP Error Message - Details

• Message type: E = Error

• Message class: FDT_WD_EXPRESSION -

• Message number: 020

• Message text: Expression &1 is not a constant

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message FDT_WD_EXPRESSION020 - Expression &1 is not a constant ?

  The SAP error message FDT_WD_EXPRESSION020 indicates that there is an issue with an expression in a Web Dynpro application where the expression is expected to be a constant, but it is not. This typically occurs in the context of using expressions in the context of data binding or UI element properties.
  Cause:
  The error arises when:
  
  An expression is defined that is expected to evaluate to a constant value, but it references a variable or a dynamic value instead.
  The expression syntax is incorrect or does not conform to the expected format for constants.
  The context in which the expression is used does not allow for non-constant values.
  
  Solution:
  To resolve this error, you can take the following steps:
  
  
  Check the Expression: Review the expression that is causing the error. Ensure that it is indeed a constant value. For example, if you are trying to set a property to a string, it should be enclosed in quotes (e.g., "MyConstantValue").
  
  
  Use Constants: If you need to use a constant, make sure you are using a defined constant or a literal value rather than a variable or a dynamic expression.
  
  
  Review Data Binding: If the expression is part of a data binding, ensure that the binding is correctly set up and that it points to a constant value or a property that can be evaluated as a constant.
  
  
  Debugging: Use the debugging tools available in the SAP Web Dynpro environment to trace the execution and see where the expression is being evaluated. This can help identify the exact point of failure.
  
  
  Documentation: Refer to the SAP documentation for Web Dynpro and expressions to ensure that you are following the correct syntax and guidelines.
  
  
  Related Information:
  
  Web Dynpro Documentation: Familiarize yourself with the Web Dynpro programming model and how expressions are evaluated.
  SAP Community: Check forums and community discussions for similar issues and solutions shared by other developers.
  SAP Notes: Look for any relevant SAP Notes that might address this specific error or provide additional context.
  
  By following these steps, you should be able to identify the cause of the error and implement a solution to resolve it.