Trigger on a view

Hi,I have a situation where I have Table A, Table B.View C is created by joining table A and table B.I have written a instead of trigger D on view C.I do not insert/update/delete on the view directly.For every insert/update in table A /B the values should get insert/update in the view respectively. This insert/update on view should invoke the trigger.And I am unable to see this trigger work on the view if any insert/update occurs on base table level.Trigger is working only if any operation is done directly on the view.Can anyone help me in this issue.Thanks in advance.