初始化:

void Widget::init()
{
    discoveryAgent = new QBluetoothDeviceDiscoveryAgent();
    localDevice = new QBluetoothLocalDevice();
    socket = new QBluetoothSocket(QBluetoothServiceInfo::RfcommProtocol);

}

绑定信号 :

void Widget::setConnect()
{
    connect(discoveryAgent,
            SIGNAL(deviceDiscovered(QBluetoothDeviceInfo)),
            this,
            SLOT(addBlueToothDevicesToList(QBluetoothDeviceInfo))
            );
    connect(ui->list,
            SIGNAL(itemClicked(QListWidgetItem*)),
            this,
            SLOT(itemActivated(QListWidgetItem*))
            );
    connect(socket,
            SIGNAL(readyRead()),
            this,
            SLOT(readBluetoothDataEvent())
            );
    connect(socket,
            SIGNAL(connected()),
            this,
            SLOT(bluetoothConnectedEvent())
            );
    connect(socket, QOverload<QBluetoothSocket::SocketError>::of(&QBluetoothSocket::error),
            [=](QBluetoothSocket::SocketError error){  qDebug() << "134error" << error ; });

    connect(socket,
            SIGNAL(disconnected()),
            this,
            SLOT(bluetoothDisconnectedEvent())
            );
 

扫描蓝牙:

void Widget::on_pushButton_scan_clicked()
{
    discoveryAgent->start();
    ui->pushButton_scan->setEnabled(false);

}

打开蓝牙:

void Widget::on_pushButton_openBluetooth_clicked()
{
    localDevice->powerOn();
    ui->pushButton_closeDevice->setEnabled(true);
    ui->pushButton_openBluetooth->setEnabled(false);
    ui->pushButton_scan->setEnabled(true);
}

关闭蓝牙:
void Widget::on_pushButton_closeDevice_clicked()
{
    localDevice->setHostMode(QBluetoothLocalDevice::HostPoweredOff);
    ui->pushButton_closeDevice->setEnabled(false);
    ui->pushButton_openBluetooth->setEnabled(true);
    ui->pushButton_scan->setEnabled(false);
}

连接蓝牙 : address 为  蓝牙的 mac 地址 字符串

   socket->connectToService(address, QBluetoothUuid(serviceUuid),QIODevice::ReadWrite);

serviceUuid  为 串口 Uuid

static const QLatin1String serviceUuid("00001101-0000-1000-8000-00805F9B34FB");

发送数据:

void Widget::sendMsg(const QString & str)
{
    QByteArray arrayData;
    arrayData = str.toUtf8();
    socket->write(arrayData);
}

接收数据:

void Widget::readBluetoothDataEvent()
{

    QByteArray line = socket->readAll();
    qDebug() << "aaaaaa";
    QString comStr = QString::fromStdString(line.toStdString());
 

    ui->textBrowser_info->append(comStr);
}

}