SAP MDG · DATA MODEL UI
How do I implement custom SAP MDG UIBB feeder logic using redefined methods in Z* classes?
Use the redefined feeder method that matches the behavior you need: `GET_DATA` for runtime field/action updates, `GET_FIELD_UI_PROP` for field editability, `PROCESS_EVENT` for event handling, and OVS phase methods for search help logic. The custom Z*UIBB classes in the knowledge base mainly extend SAP base feeders, call `super->...`, then apply context-driven logic based on the current MDG change request and process.
Use the redefined feeder method that matches the behavior you need: `GET_DATA` for runtime field/action updates, `GET_FIELD_UI_PROP` for field editability, `PROCESS_EVENT` for event handling, and OVS phase methods for search help logic. The custom Z*UIBB classes in the knowledge base mainly extend SAP base feeders, call `super->...`, then apply context-driven logic based on the current MDG change request and process.
Custom SAP MDG feeder logic in Z*UIBB classes is typically implemented by redefining only the runtime method that needs to change. The knowledge base shows two recurring patterns: `GET_DATA` for roundtrip-driven field/action behavior, and `GET_FIELD_UI_PROP` for precise per-field read-only or enabled control. Search feeders usually adjust `PROCESS_EVENT`, while OVS-enabled feeders split the logic across `HANDLE_PHASE_0` to `HANDLE_PHASE_3`.
Process flow
- Redefine only the feeder method that controls the behavior you want to change.
- Call the superclass implementation first unless you explicitly want to replace standard behavior.
- Read the MDG application context using `CL_USMD_APP_CONTEXT=>GET_CONTEXT` and retrieve CR attributes.
- Apply process-specific rules such as field editability or action usage only when the current CR context matches.
- For search help logic, split processing across the OVS phase methods instead of placing it all in `GET_DATA`.
- Set the appropriate changed flags so the framework refreshes the UI correctly.
Referenced tables
| Object | Purpose |
|---|---|
USMD120C | Read the current change request when `EV_CREQUEST_ID` is available |
TGSB | Business Area customizing / value source in related MDG feeder examples |
TGSBT | Business Area texts in related MDG feeder examples |
The remaining configuration, implementation details, and testing guidance continue from this answer more…
Related questions and keywords
Alternative questions
- Which redefined methods are most commonly used in custom Z*UIBB feeders?
- How do I adapt SAP MDG feeder behavior in GET_DATA, GET_FIELD_UI_PROP, and PROCESS_EVENT?
- How do I implement OVS phases and field-usage logic in a custom MDG UIBB feeder?
Possible questions
- Which Z*UIBB classes redefine GET_DATA?
- Which feeder methods should I use to change field editability?
- How does a custom MDG UIBB feeder read the current change request context?
- How do I implement OVS phase handling in a custom feeder?
- What is the standard pattern for PROCESS_EVENT in a Z*UIBB search feeder?