How to import QML plugins?

[Roberrt]

I have Qt compiled static, but when I run my application I get this error:

qrc:/files/particles/particles.qml:2:1: module "QtQuick.Particles" plugin "particlesplugin" not found 
     import QtQuick.Particles 2.0 
     ^

My imports related to QML are these:

import QtQuick 2.5
import QtQuick.Particles 2.0

I tried to follow the documentation:

#include <QtPlugin>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);     
    Q_IMPORT_PLUGIN(QtQuick2Plugin)
    Q_IMPORT_PLUGIN(QtQuick2ParticlesPlugin) // <--- cause error
    Q_IMPORT_PLUGIN(QtQmlMetaPlugin)
    Q_IMPORT_PLUGIN(QtQmlPlugin)
    Q_IMPORT_PLUGIN(QtQmlModelsPlugin)
    Q_IMPORT_PLUGIN(QtQmlWorkerScriptPlugin)

But I'm getting this compilation error:

1>main.obj : error LNK2019: unresolved external symbol "struct QStaticPlugin const __cdecl qt_static_plugin_QtQuick2ParticlesPlugin(void)" (?qt_static_plugin_QtQuick2ParticlesPlugin@@YA?BUQStaticPlugin@@XZ) referenced in function main

I searched the source for proper way to import this plugin and I have found it at C:\Qt\6.6.0_static\qtdeclarative\src\particles

in the file particlesplugin_init.cpp:

#include <QtPlugin>
Q_IMPORT_PLUGIN(QtQuick2ParticlesPlugin)

Why is the compilation throwing that error?

I'm compiling using Visual Studio 2022.

I tested adding #pragma comment(lib, "particlesplugin.lib") into the int main... code above

and the compiler complained about not finding the lib.

I have them added to my project properties:

C/C++ -> General -> Additional Include Directories -> C:\Qt\6.6.0_static\qml\QtQuick\Particles

Linker -> Input -> particlesplugin.lib

When recompiled, now I'm getting a different error:

1>particlesplugin.lib(particlesplugin_QtQuick2ParticlesPlugin.cpp.obj) : error LNK2019: unresolved external symbol "void __cdecl qml_register_types_QtQuick_Particles(void)" (?qml_register_types_QtQuick_Particles@@YAXXZ) referenced in function "public: static __cdecl `public: static void (__cdecl*__cdecl QtPrivate::QMetaTypeForType<class QtQuick2ParticlesPlugin>::getDefaultCtr(void))(class QtPrivate::QMetaTypeInterface const *,void *)'::`5'::<lambda_1>::<lambda_invoker_cdecl>(class QtPrivate::QMetaTypeInterface const *,void *)" (?<lambda_invoker_cdecl>@<lambda_1>@?4??getDefaultCtr@?$QMetaTypeForType@VQtQuick2ParticlesPlugin@@@QtPrivate@@SAP6AXPEBVQMetaTypeInterface@4@PEAX@ZXZ@SA@01@Z)

I also get this external symbol error for every other QtQuick plugin that I try to import using Q_IMPORT_PLUGIN and not only the particlesplugin.

I can't find anything about this in the documentation, what's going on?

[JoeCFD]

@Roberrt If you add this (static?)qtquick2plugin.lib with its path to your app, I guess it will be ok.

[Roberrt]

@JoeCFD hi, i dont understand what do you mean

[JoeCFD]

@Roberrt If you link static Qt to your app, I guess its plugins are static as well, right? If yes, you may have to add the static plugins manually to your build.

[Roberrt]

@JoeCFD said in How to import QML plugins?:

you may have to add the static plugins manually to your build.

This is what I'm trying to understand, i tried Q_IMPORT_QML_PLUGIN(qtquick2plugin) but im getting that compilation error.

[JoeCFD]

@Roberrt Maybe type the following:
how to add static qt qml plugin to app build
to chatgpt to see what you get.