AdvDBFilterDialog with previous filter (WHERE clause)

I would like to use AdvDBFilterDialog in an application with an already filtered query:

SELECT * FROM MyTable WHERE MyField = 'ABCDE' ORDER BY MyDate

when I execute the dialog it resets the filter and the order and replaces it with

SELECT * FROM MyTable

Is there a method to get only the text of the filter and process it on my own?
I have my query formated in three parts: body, filter and order, so I can add the new filter by means of "AND", append the order and execute the query.
Best Regards
Francisco Alvarado

The OnBeforeFilter event is triggered before the filter is applied. It contains the SQL command and you could change the SQL command that will be applied from this event handler.