Qt Unresolved external symbol LNK2019

Question

I know that this topic has been discussed, but i really can't find a solution for my problem. I want to read data from an XML file with QDomDocument and i get errors of this type:

main.obj:-1: error: LNK2019: unresolved external symbol “__declspec(dllimport) public: class QDomElement __cdecl QDomNode::toElement(void)const “ (__imp_?toElement@QDomNode@@QEBA?AVQDomElement@@XZ) referenced in function “void __cdecl ListElements(class QDomElement,class QString,class QString)” (?ListElements@@YAXVQDomElement@@VQString@@1@Z)

I included

#include <QCoreApplication>
#include <QtXml/QtXml>
#include <QDebug>

and i also added Qt += xml to .pro file

Answer 1

You need to run qmake after you add modules into the .pro file (that will regenerate the makefile with the correct libraries added and then the linker will find those)