QML 工程中调用 widgets 

Pro文件中添加 QT += core gui widgets quick

#include <QGuiApplication>

#include <QApplication>

#include <QQmlApplicationEngine>

#include <QQmlContext>

#include <mainwindowvm.h>

int main(int argc, char* argv[])

{

QCoreApplication::setAttribute(Qt::AA_EnableHighDpiScaling);

    QApplication app(argc, argv);

QQmlApplicationEngine engine;

const QUrl url(QStringLiteral("qrc:/main.qml"));

QObject::connect(&engine, &QQmlApplicationEngine::objectCreated,

&app, [url](QObject* obj, const QUrl& objUrl)

{

if (!obj && url == objUrl)

QCoreApplication::exit(-1);

}, Qt::QueuedConnection);

engine.load(url);

MainWindowVM MainWindowVM;

XXXXXXXXXXXXXXXtName("aaaaa");

XXXXXXXXXotContext()->setContextProperty(QT_STRINGIFY(MainWindowVM), &MainWindowVM);

return app.exec();

}

QGuiApplication 改为 QApplication 注意添加 QApplication 头文件