How to modify warnings ?

@NicKhos I’m leaving below an example of such an event action created on sub_project_tab which will trigger a toast error message. I hope this helps.

DECLARE

   functional_object_rowkey_   VARCHAR2(200) := '&NEW:CF$_EQUIPMENT_OBJECT';
   mch_code_                   VARCHAR2(200);
   project_id_                 VARCHAR2(200);
   sub_project_id_             VARCHAR2(200);

   CURSOR get_mch_code IS
          select ef.mch_code 
          from ifsapp.equipment_functional ef
          where 1=1
          and ef.objkey = functional_object_rowkey_;

   CURSOR get_sub_project_ IS
          select sp.project_id, sp.sub_project_id
          from ifsapp.sub_project_cfv sp
          where 1=1
          and sp.CF$_EQUIPMENT_OBJECT_DB = functional_object_rowkey_
          and ROWNUM = 1;

   pragma autonomous_transaction;

BEGIN

   OPEN get_sub_project_;
   FETCH get_sub_project_
      into project_id_, sub_project_id_;
   CLOSE get_sub_project_;

   IF project_id_ is not null THEN
       OPEN get_mch_code;
       FETCH get_mch_code
          into mch_code_;
       CLOSE get_mch_code;

       Error_SYS.Record_General('C_SUB_PROJECT_FO', 'FO: ' || mch_code_ || ' is already assigned to Contract: ' || project_id_ || ' and Equipment: ' || sub_project_id_ || ' You cannot assign it to another Equipment.');

   END IF;
END;