Method launch

launcher/Application.cpp:1213–1272

}

bool Application::launch(
        InstancePtr instance,
        bool online,
        bool demo,
        BaseProfilerFactory *profiler,
        MinecraftServerTargetPtr serverToJoin,
        MinecraftAccountPtr accountToUse
) {
    if(m_updateRunning)
    {
        qDebug() << "Cannot launch instances while an update is running. Please try again when updates are completed.";
    }
    else if(instance->canLaunch())
    {
        auto & extras = m_instanceExtras[instance->id()];
        auto & window = extras.window;
        if(window)
        {
            if(!window->saveAll())
            {
                return false;
            }
        }
        auto & controller = extras.controller;
        controller.reset(new LaunchController());
        controller->setInstance(instance);
        controller->setOnline(online);
        controller->setDemo(demo);
        controller->setProfiler(profiler);
        controller->setServerToJoin(serverToJoin);
        controller->setAccountToUse(accountToUse);
        if(window)
        {
            controller->setParentWidget(window);
        }
        else if(m_mainWindow)
        {
            controller->setParentWidget(m_mainWindow);
        }
        connect(controller.get(), &LaunchController::succeeded, this, &Application::controllerSucceeded);
        connect(controller.get(), &LaunchController::failed, this, &Application::controllerFailed);
        connect(controller.get(), &LaunchController::aborted, this, [this] {
            controllerFailed(tr("Aborted"));
        });
        addRunningInstance();
        controller->start();
        return true;
    }
    else if (instance->isRunning())
    {
        showInstanceWindow(instance, "console");
        return true;
    }
    else if (instance->canEdit())
    {
        showInstanceWindow(instance);
        return true;
    }