//1）業(yè)務(wù)代碼
class ComWork : public QObject {
 Q_OBJECT
public:
	ComWork();
	
signals:
   void sigSendResult(bool bOK);

public slots:
    void SendCommand(QByteArray by) {
    	qint64 nRet = m_pSerial->write(by);
    	bool bOK = (nRet != -1);
    	if(bOK)
    	   m_pSerial->flush();
    	emit sigSendResult(bOK);
    } 

private:
   QSerialPort* m_pSerial;
};

//2） 界面邏輯代碼
class ZoomWidget : public QWidget {
public:
	ZoomWidget (QWidget *parent= NULL);

protected slots:
    void OnRecvCmdResult(bool bOK);

private:
    QThread* m_pThread; //子線程
    ComWork* m_pWork;
    bool     m_bResult;
};


ZoomWidget ::ZoomWidget (QWidget *parent)
    : QWidget(parent)
{
    ui.setupUi(this);

    m_pThread = new QThread(this);
    m_pWork   = new ComWork();
    m_pWork->moveToThread(m_pThread); //m_pWork移動(dòng)到子線程里，語句(a)

    //連接信號(hào),語句(b)
    connect(m_pWork,&m_pWork::sigSendResult,this,ZoomWidget::OnRecvCmdResult);
}

ZoomWidget::OnRecvCmdResult(bool bOK)
{
	m_bResult = bOK; //語句(c)
	qDebug()<<"recv status:"<<bOK;
}

// 3）核心調(diào)用
ZoomWidget::DoSend()
{
    //進(jìn)行調(diào)用,語句(d)
	QMetaObject::invokeMethod(m_pWork, "SendCommand", Qt::QueuedConnection, Q_ARG(QByteArray, sendData));
}

QMetaMethod::invoke: Unable to invoke methods with return values in queued connections

int result = 0;
bool success = QMetaObject::invokeMethod(obj, "addNumbers",
                                         Qt::QueuedConnection, // ? 異步調(diào)用
                                         Q_RETURN_ARG(int, result),
                                         Q_ARG(int, 3),
                                         Q_ARG(int, 5));

QMetaMethod::invoke: Unable to invoke methods with return values in queued connections

int result = 0;
bool success = QMetaObject::invokeMethod(obj, "addNumbers",
                                         Qt::DirectConnection, // ? 同步調(diào)用
                                         Q_RETURN_ARG(int, result),
                                         Q_ARG(int, 3),
                                         Q_ARG(int, 5));

if (success) {
    qDebug() << "Result:" << result;
}

class Worker : public QObject {
    Q_OBJECT

signals:
    void resultReady(int result); // 用于返回結(jié)果

public slots:
    void addNumbersAsync(int a, int b) {
        int result = a + b;
        emit resultReady(result); // 發(fā)送結(jié)果
    }
};

Worker* worker = new Worker();
worker->moveToThread(thread);

// 連接信號(hào)與槽來接收結(jié)果
connect(worker, &Worker::resultReady, this, [](int res) {
    qDebug() << "異步返回結(jié)果：" << res;
});

// 異步調(diào)用
QMetaObject::invokeMethod(worker, "addNumbersAsync",
                          Qt::QueuedConnection,
                          Q_ARG(int, 3),
                          Q_ARG(int, 5));

bool QMetaObject::invokeMethod(QObject *obj, const char *member, Qt::ConnectionType type, QGenericReturnArgument ret, ...)

class Worker : public QObject {
    Q_OBJECT

public slots:
    void OpenPort(const QString &portName, int baudRate); // 必須匹配參數(shù)類型
};

Q_INVOKABLE void OpenPort(const QString &portName, int baudRate);

Q_DECLARE_METATYPE(MyCustomType)
qRegisterMetaType<MyCustomType>();

const QMetaObject* metaObj = m_pWork->metaObject();
for (int i = 0; i < metaObj->methodCount(); ++i) {
    qDebug() << metaObj->method(i).signature();
}