SAP/ABAP: POPUP_CONTINUE_YES_NO FM

FORM onay CHANGING p_answer.
  CLEAR p_answer.
  CALL FUNCTION 'POPUP_CONTINUE_YES_NO'
    EXPORTING
      defaultoption = 'N'
      textline1     = type text here'
      textline2     = 'if necessary, you can type text here too'
      titel         = 'title'
    IMPORTING
      answer        = p_answer
    EXCEPTIONS
      OTHERS        = 1.
ENDFORM.