C++调用qml对象Demo

#include <QGuiApplication> #include <QQmlApplicationEngine> #include "ChangeColor.h" #include <QDebug> #include <QColor> int main(int argc, char *argv[]) { QCoreApplication::setAttribute(Qt::AA_EnableHighDpiScaling); QGuiApplication 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); QObject *root = nullptr; QList<QObject*> rootObjects = engine.rootObjects(); int count = rootObjects.count(); for(int i = 0; i < count; ++i) { if(rootObjects.at(i)->objectName() == "rootObject") { root = rootObjects.at(i); break; } } new ChangeColor(root); QObject *quitButton = root->findChild<QObject*>("quitButton"); if(quitButton) { QObject::connect(quitButton, SIGNAL(clicked()), &app, SLOT(quit())); } QObject *textLabel = root->findChild<QObject*>("textLabel"); if(textLabel) { bool bRet = QMetaObject::invokeMethod(textLabel, "setText", Q_ARG(QString, "helloword！")); qDebug() << "call setText return - " << bRet; textLabel->setProperty("color", QColor::fromRgb(255, 0, 0)); bRet = QMetaObject::invokeMethod(textLabel, "doLayout"); qDebug() << "call doLayout return - " << bRet; } return app.exec(); }