Since you can define more than one custom controller for each Web Dynpro application at design time, you must reference the custom controller that is to be used at runtime.
You have defined a Web Dynpro component for your current project as well as a component usage.
You reference the custom controller starting from the component controller. Proceed as follows:
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1. In the Web Dynpro Explorer, double-click the controller of the Web Dynpro component.
2. Choose the Properties tab in the right screen area.
3. Choose Add.
4. Select the relevant custom controller and confirm by choosing OK.
5. Save by choosing Save all Metadata.
The referenced custom controller is displayed in the list of Required Controllers on the Properties tab of the component.