Undefined reference when using Cmake and QtCreator - c++

Question

I'm running the basic OpenCV example with OpenCV3.0.0 dev:
project(ImageDenoise)
cmake_minimum_required(VERSION 2.8)
aux_source_directory(. SRC_LIST)
find_package(OpenCV REQUIRED)
include_directories( ${OpenCV_INCLUDE_DIRS} )
add_executable(${PROJECT_NAME} ${SRC_LIST})
target_link_libraries(${PROJECT_NAME} ${OpenCV_LIBS})
MESSAGE(${OpenCV_LIBS})
MESSAGE(${OpenCV_INCLUDE_DIRS})
Source code:
#include <iostream>
#include <opencv2/core/core.hpp>
#include <opencv2/highgui/highgui.hpp>
using namespace cv;
using namespace std;
int main(int argc, char* argv[] )
{
if ( argc != 2 )
{
printf("usage: DisplayImage.out <Image_Path>\n");
return -1;
}
Mat image;
image = imread( argv[1], IMREAD_COLOR );
if ( !image.data )
{
printf("No image data \n");
return -1;
}
namedWindow("Display Image", WINDOW_AUTOSIZE );
imshow("Display Image", image);
waitKey(0);
return 0;
}
When I import this project into QtCreator, I got the following linking errors when building project:
[100%] Building CXX object CMakeFiles/ImageDenoise.dir/main.cpp.o
Linking CXX executable ImageDenoise
CMakeFiles/ImageDenoise.dir/main.cpp.o: In function `main':
main.cpp:(.text+0x7c): undefined reference to `cv::imread(cv::String const&, int)'
main.cpp:(.text+0xf5): undefined reference to `cv::namedWindow(cv::String const&, int)'
main.cpp:(.text+0x144): undefined reference to `cv::imshow(cv::String const&, cv::_InputArray const&)'
However when I run cmake from command line and using make, then it works perfectly. What is the reason behind this?
dzung#Cronus:~/kSVD/build$ make
Scanning dependencies of target ImageDenoise
[100%] Building CXX object CMakeFiles/ImageDenoise.dir/main.cpp.o
Linking CXX executable ImageDenoise
[100%] Built target ImageDenoise
dzung#Cronus:~/kSVD/build$ ls
CMakeCache.txt CMakeFiles cmake_install.cmake ImageDenoise Makefile
dzung#Cronus:~/kSVD/build$ ./ImageDenoise
usage: DisplayImage.out <Image_Path>

Answer 1

I had exactly the same issue. I think this is some sort of a Qt-creator bug.
I solved this by:
Remove everything except *.cpp and CMakeLists.txt in the project
folder.
Before creating anything with Qt-creator do: cmake . && make
Now open existing project in Qt-creator.
Now you can run cmake/compile/run etc just fine.