Here's an example for displaying the log (I only pass the date values here):
CALL FUNCTION 'APPL_LOG_DISPLAY'
EXPORTING
object = 'ZCD_MI_POST'
date_from = lv_date_from
date_to = lv_date_to
suppress_selection_dialog = 'X'
IMPORTING
number_of_protocols = lv_number
EXCEPTIONS
no_authority = 1
OTHERS = 2.
If you want to have the standard selection screen displayed, just set suppress_selection_dialog to space.