Re: [Discuss-gnuradio] QT GUI FFTSINK in C++ Flowgraph

[Tom Rondeau]

On Wed, Dec 19, 2012 at 2:56 AM, Daniel Labarowski <address@hidden> wrote:

Thanks for the replies guys. Tom, I have modified this flowgraph (extensively) from one of the examples and have been using its CMakeLists.txt file (modifying it along the way of course). The commands that I use to build it are

mkdir build
cd build
cmake ../
make

I believe that -l gnuradio-qtgui would be for g++. Since I am not using g++ directly I tried adding the following to my CMakeLists.txt file.

# libgnuradio-qtgui.so
#find_package(gnuradio-qtgui)
include_directories(/usr/local/lib)

When the find_package command did not work, I commented it out and included the directory absolutely. I have had to do this a lot lately. Some of the library variables seem to have not gotten set by the build script (granted, this build is from the summer). Unfortunately I am still getting the

undefined reference to `qtgui_make_sink_c(int, int, double, double, std::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, bool, bool, bool, bool, QWidget*)'

error. My syntax is

qtgui_sink_c_sptr qtsink = qtgui_make_sink_c (fftsize, gr_firdes::WIN_HAMMING, 0, 1.0, "Spectrum Display", true, true, true, true, NULL);

I am including the following relevant components

#include <qtgui_sink_c.h>
#include <QApplication>
#include <QWidget>

Can anyone spot my mistake?

-Dan

Hi Dan,

The problem is not in the includes, its in the linking library.  Try using:

target_link_libraries(<target to build> <list of libraries like gnuradio-qtgui>)

Tom