How To Fix /UI5/APP_API042 - Can't convert object or array to simple type

SAP Error Message - Details

• Message type: E = Error

• Message class: /UI5/APP_API -

• Message number: 042

• Message text: Can't convert object or array to simple type

Self-Explanatory Message

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Smart SAP Assistant

• What is the cause and solution for SAP error message /UI5/APP_API042 - Can't convert object or array to simple type ?

  The SAP error message /UI5/APP_API042 Can't convert object or array to simple type typically occurs in the context of SAP Fiori applications that use the UI5 framework. This error indicates that there is an issue with data binding or data conversion, where the application is trying to convert a complex object or an array into a simple type (like a string, number, or boolean), which is not possible.
  Causes:
  
  Data Structure Mismatch: The data being returned from the backend (e.g., OData service) is not in the expected format. For example, if the UI5 application expects a simple type but receives an object or array instead.
  Incorrect Binding: The UI5 application may be trying to bind a complex object to a UI control that expects a simple type.
  Model Definition Issues: The model might not be defined correctly, leading to incorrect data types being inferred.
  Backend Service Issues: The OData service might be returning unexpected data due to issues in the backend logic or data model.
  
  Solutions:
  
  Check Data Structure: Verify the structure of the data being returned from the backend service. Ensure that it matches the expected format in the UI5 application.
  Adjust Data Binding: Review the binding paths in your UI5 application. Make sure that you are binding complex objects to controls that can handle them (e.g., using a List or Table for arrays).
  Modify the OData Service: If the backend service is returning an object or array where a simple type is expected, consider modifying the service to return the correct data type.
  Use Formatter Functions: If you need to display a property of an object, consider using a formatter function to extract the necessary value from the object before binding it to the UI control.
  Debugging: Use browser developer tools to inspect the network requests and responses. Check the data being returned and ensure it aligns with what the UI5 application expects.
  
  Related Information:
  
  UI5 Documentation: Refer to the official SAP UI5 documentation for guidelines on data binding and model definitions.
  OData Service Documentation: Review the OData service documentation to understand the expected data formats and types.
  SAP Community: Engage with the SAP Community forums for insights and solutions from other developers who may have encountered similar issues.
  
  By following these steps, you should be able to identify the root cause of the error and implement a suitable solution.