Some basic question

[ZekDe]

Hi friends,
I am using Qt Creature to form applications and to new C++(not C) adventure I encountered like question below.

what is static_cast here, <>, actually I never understand thes code

 
 static_cast<void (QSerialPort::*)(QSerialPort::SerialPortError)>
(&QSerialPort::error) 

  connect(serial, static_cast<void (QSerialPort::(QSerialPort::SerialPortError)>(&QSerialPort::error),this, &MainWindow::handleError);

also

public:
    struct Settings {
        QString name;
        qint32 baudRate;
        QString stringBaudRate;
        QSerialPort::DataBits dataBits;
        QString stringDataBits;
        QSerialPort::Parity parity;
        QString stringParity;
        QSerialPort::StopBits stopBits;
        QString stringStopBits;
        QSerialPort::FlowControl flowControl;
        QString stringFlowControl;
        bool localEchoEnabled;
    };

    explicit SettingsDialog(QWidget *parent = nullptr);
    ~SettingsDialog();

    Settings settings() const;  --> what does it mean?

Thanks to helps

[coder777]

what is static_cast here

It casts a function pointer to a pointer to a member function of the class QSerialPort that take the parameter QSerialPort::SerialPortError

--> what does it mean?

The const promises the caller of that function that no member variables are changed during the call.