Qt on android 蓝牙开发(控制小车)

因为要做一个用蓝牙控制小车的app，就用着QT搞了下，网上关于QT蓝牙开发的资料比较少，我在这里记录下过程希望对看到了人有所帮助首先在项目文件里添加QT += bluetooth这样就可以用QT关于蓝牙的一系列类了，接下来在添加头文件#include <QtBluetooth/qbluetoothglobal.h>#include <Qt...

@jhang

1615人浏览 · 2018-05-23 21:34:00

@jhang · 2018-05-23 21:34:00 发布

因为要做一个用蓝牙控制小车的app，就用着QT搞了下，网上关于QT蓝牙开发的资料比较少，我在这里记录下过程希望对看到了人有所帮助

首先在项目文件里添加

QT += bluetooth

这样就可以用QT关于蓝牙的一系列类了，接下来在添加头文件

#include <QtBluetooth/qbluetoothglobal.h>
#include <QtBluetooth/qbluetoothlocaldevice.h>
#include <qbluetoothaddress.h>
#include <qbluetoothdevicediscoveryagent.h>
#include <qbluetoothlocaldevice.h>
#include <qbluetoothsocket.h>

添加要用的私有成员变量

private:
    Ui::BLE *ui;
    QBluetoothDeviceDiscoveryAgent *discoveryAgent;
    QBluetoothLocalDevice *localDevice;
    QBluetoothSocket *socket;

构造函数

discoveryAgent = new QBluetoothDeviceDiscoveryAgent();
    localDevice = new QBluetoothLocalDevice();
    /* 给socket分配内存，限定套接字协议 */
    socket = new QBluetoothSocket(QBluetoothServiceInfo::RfcommProtocol);
    /* 判断蓝牙是否开启，若开启则不可被选中并扫描周围蓝牙设备 */
    if( localDevice->hostMode() == QBluetoothLocalDevice::HostPoweredOff )
    {
        ui->pushButton_openBLE->setEnabled(true);
        ui->pushButton_upDateBLE->setEnabled(false);
        /* 开始扫描蓝牙设备 */
        discoveryAgent->start();
    }
    else
    {
        ui->pushButton_openBLE->setEnabled(false);
        ui->pushButton_upDateBLE->setEnabled(true);
    }
    /* 发现设备时会触发deviceDiscovered信号，转到槽显示蓝牙设备 */
    connect(discoveryAgent, SIGNAL(deviceDiscovered(QBluetoothDeviceInfo)),
            this, SLOT(addBlueToothDevicesToList(QBluetoothDeviceInfo)));
    connect(discoveryAgent, SIGNAL(finished()), this, SLOT(findFinish()));
    /* 双击listwidget的项目，触发连接蓝牙的槽 */
    connect(ui->listWidget, SIGNAL(itemActivated(QListWidgetItem*)),
            this, SLOT(connectBLE(QListWidgetItem*)));
    connect(socket, SIGNAL(connected()), this, SLOT(connectOK()));
    connect(socket, SIGNAL(disconnected()), this, SLOT(connectNot()));

下面是各个槽函数实现

/* 打开蓝牙并查找蓝牙设备 */
void BLE::on_pushButton_openBLE_clicked()
{
    localDevice->powerOn();
    ui->pushButton_openBLE->setEnabled(false);
    ui->pushButton_upDateBLE->setEnabled(true);
    /* 开始扫描蓝牙设备 */
    discoveryAgent->start();
}
/* 刷新 重新查找蓝牙设备 */
void BLE::on_pushButton_upDateBLE_clicked()
{
    discoveryAgent->start();
    ui->pushButton_upDateBLE->setEnabled(false);
}
/* 返回控制页面 */
void BLE::on_pushButton_return_clicked()
{
    this->hide();
    Control *c = new Control();
    c->show();
}
/* 在ListWidget上显示查找到的蓝牙设备 */
void BLE::addBlueToothDevicesToList(const QBluetoothDeviceInfo &info)
{
    QString label = QString("%1 %2").arg(info.address().toString()).arg(info.name());

    QList<QListWidgetItem *> items = ui->listWidget->findItems(label, Qt::MatchExactly);

    if (items.empty()) {
        QListWidgetItem *item = new QListWidgetItem(label);
        QBluetoothLocalDevice::Pairing pairingStatus = localDevice->pairingStatus(info.address());
        /* 蓝牙状态pairingStatus，Pairing枚举类型 0:Unpaired没配对 1:Paired配对但没授权 2:AuthorizedPaired配对且授权 */
        if (pairingStatus == QBluetoothLocalDevice::Paired || pairingStatus == QBluetoothLocalDevice::AuthorizedPaired )
            item->setTextColor(QColor(Qt::green));
        else
            item->setTextColor(QColor(Qt::black));
        ui->listWidget->addItem(item);
    }
}
/* 刷新完成 */
void BLE::findFinish()
{
    ui->pushButton_upDateBLE->setEnabled(true);
}
/* 蓝牙连接 */
void BLE::connectBLE(QListWidgetItem *item)
{
    QString text = item->text();
    int index = text.indexOf(' ');
    if (index == -1)
        return;
    QBluetoothAddress address(text.left(index));
    QString name(text.mid(index + 1));
    QMessageBox::information(this,tr("Info"),tr("The device is connecting..."));
    socket->connectToService(address, QBluetoothUuid(serviceUuid) ,QIODevice::ReadWrite);
}
/* 连接成功 */
void BLE::connectOK()
{
    discoveryAgent->stop();  //停止搜索设备
    QMessageBox::information(this, tr("成功"), tr("连接成功!"));
}
/* 连接失败 */
void BLE::connectNot()
{
    QMessageBox::information(this, tr("错误"), tr("连接失败!"));
}

不要忘记设置蓝牙的uuid码

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

蓝牙的发送、读取数据和服务器客户端发送读取数据一样，发送数据用write() 读取数据先接收到readyRead()信号然后用readAll()读取

现在构造函数中添加信号和槽连接

connect(socket, SIGNAL(readyRead()), this, SLOT(readBluetoothDataEvent()));

槽函数

void BLE::readBluetoothDataEvent()
{

    QByteArray line = socket->readAll();
    QString strData = line.toHex();
    comStr.append(strData);
    qDebug() <<"rec data is: "<< comStr;
    qDebug() <<"The comStr length is: " << comStr.length();
    if(comStr.length() >= 30) {

        ui->textBrowser_info->append(comStr + "\n");
        comStr.clear();
    }

}

OK啦

下面附一个我的蓝牙控制小车的源码

链接：https://pan.baidu.com/s/15JjHSm-KQIsbN-zHOFW6IQ 密码：nxc0