Function getApp

src/ui/main.cpp:101–138

factory method to build and return a suitable Qt application instance it remembers a previously created instance, and will return it if available otherwise a new one is created and configure caution: cannot use .exec() any more, instead call .show() and use QApplication::exec()

// otherwise a new one is created and configure
// caution: cannot use <widget>.exec() any more, instead call <widget>.show() and use QApplication::exec()
QCoreApplication* getApp(char** argv) {
    if (QCoreApplication::instance() != nullptr)
        return QCoreApplication::instance();

    // build application version string
    std::string version;
    {
        std::ostringstream oss;
        oss << "version " << APPIMAGELAUNCHER_VERSION << " "
            << "(git commit " << APPIMAGELAUNCHER_GIT_COMMIT << "), built on "
            << APPIMAGELAUNCHER_BUILD_DATE;
        version = oss.str();
    }

    QCoreApplication* app;

    // need to pass rvalue, hence defining a variable
    int* fakeArgc = new int{1};

    static char** fakeArgv = new char*{strdup(argv[0])};

    if (isHeadless()) {
        app = new QCoreApplication(*fakeArgc, fakeArgv);
    } else {
        auto uiApp = new QApplication(*fakeArgc, fakeArgv);
        QApplication::setApplicationDisplayName("AppImageLauncher");

        // this doesn't seem to have any effect... but it doesn't hurt either
        uiApp->setWindowIcon(QIcon(":/AppImageLauncher.svg"));

        app = uiApp;
    }

    QCoreApplication::setApplicationName("AppImageLauncher");
    QCoreApplication::setApplicationVersion(QString::fromStdString(version));

    return app;
}

int main(int argc, char** argv) {
    // create a suitable application object (either graphical (QApplication) or headless (QCoreApplication))