Spdlog library can't open in the Qt.

[KroMignon]

@Enes-Alp said in Spdlog library can't open in the Qt.:

Did you try to start it in debug mode with Qt Creator?
I guess the connect() statement is what will stop your application.

QObject::connect(
&engine, &QQmlApplicationEngine::objectCreated, &app,
[url](QObject *obj, const QUrl &objUrl) {
if (!obj && url == objUrl)
QCoreApplication::exit(-1);
},
Qt::QueuedConnection);

Why do you check url? The interesting parameter is obj. When obj is null, the instance could not be created.

[Enes Alp]

yes I tried the debug and release mode? Also I'm using msvc2019-64bit but when I changed the mingw, I get some linker error.
URL require for qml side.

[KroMignon]

@Enes-Alp said in Spdlog library can't open in the Qt.:

I'm using msvc2019-64bit but when I changed the mingw, I get some linker error.

If you change Qt Kit from MSVC2019-64bit to mingw, you also have to use a compatible spdlog and fmt build version.

I guess the problem is in the QML code / import path.
Try to set the environment variable QML_IMPORT_TRACE to got QML traces.
You can do it in code, like this:

int main(int argc, char *argv[]) {
#if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
  QCoreApplication::setAttribute(Qt::AA_EnableHighDpiScaling);
#endif

  qputenv("QML_IMPORT_TRACE", "1");
  QGuiApplication app(argc, argv);

  QQmlApplicationEngine engine;
  engine.addImportPath("qrc:/");
  const QUrl url(QStringLiteral("qrc:/views/MasterView.qml"));
  engine.load(url);

  return app.exec();
}

[Enes Alp]

The problem is with spd functions.
When I added the below code, I get a crash.

spdlog::info("....");

[KroMignon]

@Enes-Alp said in Spdlog library can't open in the Qt.:

The problem is with spd functions.
When I added the below code, I get a crash

How did you build spdlog library?
Did you use same compiler (MSVC2019-64bit)?

[Enes Alp]

I installed with vcpkg like this ./vcpkg.exe install spdlog:x64-windows. I didn't compile because the spdlog has static compilation files(spdlog.lib, fmt.lib). I added just include and .lib files.

##- spdlog installed by default c:/dev/vcpkg
SPDLOG_ROOT = c:/dev/vcpkg/installed/x64-windows
exists($$SPDLOG_ROOT) {
    LIBS        += -L$$SPDLOG_ROOT/lib -lspdlog -lfmt

    INCLUDEPATH += $$SPDLOG_ROOT/include
    DEPENDPATH += $$SPDLOG_ROOT/include

    DESTDIR_WIN = $$replace(DESTDIR, "/", "\\")
    SPDLOG_ROOT_WIN = $$replace(SPDLOG_ROOT, "/", "\\")
}

[SGaist]

Hi,

Are you sure that these libs are static ? A .lib file can either be a static library or import library that will require the use of a dll at run time.

[Enes Alp]

I don't have any dll file in the lib folder.

[SGaist]

Then start your application through the debugger to get a stack trace of the crash.

[JohanSolo]

@SGaist said in Spdlog library can't open in the Qt.:

Are you sure that these libs are static ? A .lib file can either be a static library or import library that will require the use of a dll at run time.

The spdlog library is either header-only or static.

[Enes Alp]

@SGaist
The problem is in the spdlog::info function line. When I delete this line, I don't get errors.

[SGaist]

Do you have it working if you copy the code of the examples in the library documentation (without any Qt stuff) ?

[Pablo J. Rogina]

@Enes-Alp said in Spdlog library can't open in the Qt.:

The problem is in the spdlog::info function line

Have you tried the header-only approach?

[Enes Alp]

Yes, I tried but I get the same result.

#include <spdlog/spdlog.h>

int main() {

  spdlog::info("Welcome to spdlog");

  return 0;
}

QT -= gui

CONFIG += c++11 console
CONFIG -= app_bundle

##- spdlog installed by default c:/dev/vcpkg

SPDLOG_ROOT = c:/dev/vcpkg/installed/x64-windows

exists($$SPDLOG_ROOT) {
    LIBS        += -L$$SPDLOG_ROOT/lib -lspdlog -lfmt

    INCLUDEPATH += $$SPDLOG_ROOT/include
    DEPENDPATH += $$SPDLOG_ROOT/include

    DESTDIR_WIN = $$replace(DESTDIR, "/", "\\")
    SPDLOG_ROOT_WIN = $$replace(SPDLOG_ROOT, "/", "\\")
}


# You can make your code fail to compile if it uses deprecated APIs.
# In order to do so, uncomment the following line.
#DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000    # disables all the APIs deprecated before Qt 6.0.0

SOURCES += \
        main.cpp

# Default rules for deployment.
qnx: target.path = /tmp/$${TARGET}/bin
else: unix:!android: target.path = /opt/$${TARGET}/bin
!isEmpty(target.path): INSTALLS += target
`

[KroMignon]

@Enes-Alp said in Spdlog library can't open in the Qt.:

Yes, I tried but I get the same result.

But you don't have change anything, so the result will still be the same.
Header only approach means you add each spdlog header file in INCLUDES and remove spdlog from LIBS.

[Enes Alp]

@KroMignon

The Header-only approach is working but how can I add a static link?

INCLUDEPATH += C:/Users/enesa/Documents/Test-Qt-Cpp/include/spdlog/include

[SGaist]

The concept of header only librairies is that you do not have anything to link.

[Enes Alp]

@SGaist

In the doc, the static lib version is much faster in compile time.
What is the meaning of this, you know?

[SGaist]

The header only library means that you do not have to link anything but this means that you will build everything you use from it on each build.