autotools: detect wxWidgets version via wx-config (wxWidgets 2.8/debian testing support)

configure.ac

 AM_CONDITIONAL(AUDIO_PORTAUDIO2, [test x"$AUDIO" = xportaudio2])
 AM_CONDITIONAL(AUDIO_SADA,       [test x"$AUDIO" = xsada])
 
+dnl ================================================================
+dnl wxWidgets checks.
+dnl ================================================================
+
+AC_CHECK_PROG(WXCONFIG_CHECK,wx-config,yes)
+if test x"$WXCONFIG_CHECK" != x"yes" ; then
+    AC_MSG_ERROR([Please install wxWidgets which is needed for espeakedit.])
+fi
+
+WX_LIBS=`wx-config --libs`
+WX_CXXFLAGS=`wx-config --cxxflags`
+WX_VERSION=`wx-config --version`
+
+AC_SUBST(WX_LIBS)
+AC_SUBST(WX_CXXFLAGS)
+
 dnl ================================================================
 dnl Generate output.
 dnl ================================================================
         Compiler:                      ${CXX}
         Compiler flags:                ${CXXFLAGS}
 
+        wxWidgets:                     ${WX_VERSION}
 	pulseaudio:                    ${have_pulseaudio}
 	audio configuration:           ${AUDIO}
 ])

src/Makefile.am

 	spectdisplay.cpp spectseq.cpp \
 	transldlg.cpp voicedlg.cpp vowelchart.cpp $(WAVE)
 espeakedit_OBJS=${espeakedit_SOURCE:%.cpp=e_%.o}
-espeakedit_WX_LIBS = -pthread   -lwx_gtk2u_xrc-2.6 -lwx_gtk2u_qa-2.6 -lwx_gtk2u_html-2.6 \
-	-lwx_gtk2u_adv-2.6 -lwx_gtk2u_core-2.6 -lwx_baseu_xml-2.6 -lwx_baseu_net-2.6 -lwx_baseu-2.6
 espeakedit_LIBS=-lstdc++ $(LIB_AUDIO)
-espeakedit_CXXFLAGS = -I/usr/lib/wx/include/gtk2-unicode-release-2.6 \
-	-I/usr/include/wx-2.6 \
-	-DGTK_NO_CHECK_CASTS -D__WXGTK__ -D_FILE_OFFSET_BITS=64 \
-	-D_LARGE_FILES -D_LARGEFILE_SOURCE=1 -DNO_GCC_PRAGMA -D_ESPEAKEDIT
+espeakedit_CXXFLAGS = ${WX_CXXFLAGS} -D_LARGEFILE_SOURCE=1 -DNO_GCC_PRAGMA -D_ESPEAKEDIT
 $(ESPEAKEDIT): $(espeakedit_OBJS)
-	$(CXX) $(LDFLAGS) -o $@ $(espeakedit_OBJS) $(espeakedit_LIBS) $(espeakedit_WX_LIBS)
+	$(CXX) $(LDFLAGS) -o $@ $(espeakedit_OBJS) $(espeakedit_LIBS) ${WX_LIBS}
 
 clean:
 	rm -f *.o *.a *~