how to add extra_compiler works like ui compiler?

I want to preprocess some slice files with the preprocess compiler slice2cpp,it will compile slice file and generate cpp and header file.
I add the extra compiler as following , it works,but it only add cpp file dependency to makefile,while I want add both cpp and header file ,just like what qmake process UI file.
anyone can help me ?

Code:

---

slice_cpp.output = ${QMAKE_FILE_BASE}.cpp
slice_cpp.input = SLICE_FILES
slice_cpp.commands=slice2cpp --underscore ${QMAKE_FILE_IN} -I ../slice -I  $$ICE_SLICE_PATH
slice_cpp.name= "ice preprocesor"
slice_cpp.variable_out= SOURCES
QMAKE_EXTRA_COMPILERS += slice_cpp

---

Check the yacc.prf file.