Question

这是我的代码：我有一个名为bluetoothCommunication的类，我需要在其中放置一些通过蓝牙交换数据的方法。

 bluetoothCommunication::bluetoothCommunication()
{
    QBluetoothLocalDevice localDevice;
    QString localDeviceName;
    //Check if Bluetooth is available on this device
    if(localDevice.isValid()){
        //Turn Bluetooth on
        localDevice.powerOn();
        //Read local device name
        localDeviceName = localDevice.name();
        //Make it visible to others
        localDevice.setHostMode(QBluetoothLocalDevice::HostDiscoverable);
        //Get connected devices
        QList<QBluetoothAddress> remotes;
        remotes = localDevice.connectedDevices();
    }
}

void bluetoothCommunication::startDeviceDiscovery()
    {
    qDebug() << "Bluetooth discovery started";

    //Create a discovery agent and connect to its signals
    QBluetoothDeviceDiscoveryAgent* discoveryAgent = new QBluetoothDeviceDiscoveryAgent();
    QObject::connect(discoveryAgent, SIGNAL(deviceDiscovered(QBluetoothDeviceInfo*)), &this, SLOT(deviceDiscovered(QBluetoothDeviceInfo*))); //HERE I HAVE AN ERROR //DON'T KNOW WHERE AND WHY
    //Start a discovery
    discoveryAgent -> start();
}

我试图修改qt文档中的官方示例（如下所示），如果我复制并粘贴它，会在编译时出错：

    void MyClass::startDeviceDiscovery()
{
// Create a discovery agent and connect to its signals
QBluetoothDeviceDiscoveryAgent *discoveryAgent = new QBluetoothDeviceDiscoveryAgent(this);
connect(discoveryAgent, SIGNAL(deviceDiscovered(QBluetoothDeviceInfo)),
        this, SLOT(deviceDiscovered(QBluetoothDeviceInfo)));

// Start a discovery
discoveryAgent->start();

//...
}

但是我尝试修复它仍然无效。有错误消息：

在成员函数void bluetoothCommunication::startDeviceDiscovery()中：需要左值一元&操作数

Answer 1

因此，在sample documentation之后，我设法生成了一小段代码编译样本。

开始笔记：

您需要QtCreator 5.2或更高版本来编译QBluetooth库。
在.pro文件中添加Qt + = bluetooth
使用Qt文档提供的示例
在头文件中包含所有库并添加方法定义。

<强> bluetoothSample.pro

QT       += core gui
greaterThan(QT_MAJOR_VERSION, 4): QT += widgets bluetooth

TARGET = bluetoothSample
TEMPLATE = app

DEFINES += QT_DEPRECATED_WARNINGS

#DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000 

SOURCES += main.cpp\
    mainwindow.cpp

HEADERS  += mainwindow.h

FORMS    += mainwindow.ui

<强> mainWindow.h

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>
#include <QBluetoothDeviceDiscoveryAgent>
#include <QBluetoothDeviceInfo>

namespace Ui {
  class MainWindow;
}

class MainWindow : public QMainWindow
{
  Q_OBJECT

private:
  Ui::MainWindow *ui;
  void startDeviceDiscovery();

private slots:
  void deviceDiscovered(const QBluetoothDeviceInfo &device);
};

#endif // MAINWINDOW_H

<强> mainWindow.cpp

#include "mainwindow.h"
#include "ui_mainwindow.h"

#include <QDebug>

void MainWindow::startDeviceDiscovery()
{
  // Create a discovery agent and connect to its signals
  QBluetoothDeviceDiscoveryAgent *discoveryAgent = new QBluetoothDeviceDiscoveryAgent(this);
  connect(discoveryAgent, SIGNAL(deviceDiscovered(QBluetoothDeviceInfo)),
        this, SLOT(deviceDiscovered(QBluetoothDeviceInfo)));

  // Start a discovery
  discoveryAgent->start();

  //...
}

// In your local slot, read information about the found devices
void MainWindow::deviceDiscovered(const QBluetoothDeviceInfo &device)
{
  qDebug() << "Found new device:" << device.name() << '(' << device.address().toString() << ')';
}

Answer 2

我有标准示例的扫描问题我解决了问题，删除了uuid filtr：

// m_discoveryAgent-＆GT; setUuidFilter（UUID）; 发现的设备。

在Qt中扫描蓝牙设备

2 个答案: