QObject::connect: signal not found in

[Victorusik]

Problem with signals in dynamic libraries.

When I use mylib SHARED an error qt.core.qobject.connect: QObject::connect: signal not found in TestLib occure.

But if mylib STATIC it works correctly

Why can't connect() find signal if it's in dll lybrary?

---

Below: CMakeLists.txt, mainwindow.cpp, testlib.h, testlib.cpp

// CMakeLists.txt
qt_add_library(mylib SHARED
        testlib.cpp
        testlib.h
)

target_link_libraries(mylib
        PUBLIC
        Qt6::Core
)

qt_add_executable(main main.cpp
        mainwindow.cpp
        mainwindow.h
)

target_link_libraries(main PRIVATE
        Qt6::Core
        Qt6::Widgets
        mylib
)

// mainwindow.cpp
MainWindow::MainWindow(QWidget *parent)
 : QMainWindow(parent), lib(new TestLib)
 {
    bool connected = connect(lib, &TestLib::testSignal, this, []() {
        qDebug() << "Test Signal";
    });
    // If mylib SHARED -> error
    // If mylib STATIC -> Test Signal appears in console
    lib->interaptSig();
}

// testlib.h
#ifndef TESTLIB_H
#define TESTLIB_H

#include <QObject>

class TestLib : public QObject {
    Q_OBJECT

signals:
    void testSignal();

public:
    TestLib(QObject *parent = nullptr);

    void interaptSig();
};
#endif //TESTLIB_H

// testlib.cpp
#include "testlib.h"


TestLib::TestLib(QObject *parent) : QObject(parent) {}

void TestLib::interaptSig() {
    emit testSignal();
}

[Christian Ehrlicher]

When you're on windows you forgot to export the class.