我是靠谱客的博主 英勇马里奥，最近开发中收集的这篇文章主要介绍ROS下基于Qt的人机交互开发（四）在Qt中发布和订阅话题前言一、创建节点二、发布话题三、订阅话题四、键盘控制五、运行终端命令六、案例源码，觉得挺不错的，现在分享给大家，希望可以做个参考。
概述
目录
前言
一、创建节点
二、发布话题
三、订阅话题
四、键盘控制
五、运行终端命令
六、案例源码
前言
本案例包括
- 在Qt中创建节点
- 发布话题控制海龟移动
- 订阅话题实时显示海龟位置。
- 键盘控制实现
- qt中运行终端命令
本案例是在ros中创建的qt功能包的基础进行的，在ros中创建qt功能包可以参考下文
ROS下基于Qt的人机交互开发（一）开发环境搭建
https://blog.csdn.net/m0_56451176/article/details/126122360?spm=1001.2014.3001.5502
一、创建节点
bool QNode::init()
{
//初始化ROS节点“ros_qt_demo”
ros::init(init_argc,init_argv,"ros_qt_demo");
//检测ROS节点是否打开
if ( ! ros::master::check() )
{
return false;
}
//启动
ros::start();
//创建句柄
ros::NodeHandle n;
//创建发布者
chatter_publisher = n.advertise<std_msgs::String>("chatter", 1000);
//调用run（）
start();
return true;
}
注：这个qt功能包自带的init有两种形式，两种init函数中内容相似
二、发布话题
命令行发布话题请参考：
ROS学习（四）--1.发布者与订阅者案例https://blog.csdn.net/m0_56451176/article/details/126222244?spm=1001.2014.3001.5502
1.在头文件中创建发布者对象turtle_vel_pub;
ros::Publisher turtle_vel_pub;2.在源文件中定义发布者（init（）中定义，即上文发布者所在函数中）
turtle_vel_pub = n.advertise<geometry_msgs::Twist>("/turtle1/cmd_vel", 10);3.在run（）函数中发布消息
void QNode::run() {
ros::Rate loop_rate(1);
int count = 0;
while ( ros::ok() )
{
geometry_msgs::Twist vel_msg;
vel_msg.linear.x = linevelocity*0.01;
vel_msg.angular.z = angular*0.01;
// 发布消息
turtle_vel_pub.publish(vel_msg);
ros::spinOnce();
loop_rate.sleep();
++count;
}
std::cout << "Ros shutdown, proceeding to close the gui." << std::endl;
Q_EMIT rosShutdown(); // used to signal the gui for a shutdown (useful to roslaunch)
}在while ( ros::ok() )循环中添加要发布的信息
geometry_msgs::Twist vel_msg;
vel_msg.linear.x = linevelocity*0.01;
vel_msg.angular.z = angular*0.01;本案例定义了要发布的信息为：海龟x方向线速度和z方向角速度
发布话题：
turtle_vel_pub.publish(vel_msg);总结：
- 创建发布者
- 定义消息类型和内容
- 发布消息
三、订阅话题
命令行订阅话题请参考：
ROS学习（四）--1.发布者与订阅者案例https://blog.csdn.net/m0_56451176/article/details/126222244?spm=1001.2014.3001.5502
1.在头文件中创建发布者对象pose_sub;
ros::Subscriber pose_sub;2.在源文件中定义发布者（init（）中定义，即上文发布者所在函数中）
pose_sub = n.subscribe("/turtle1/pose", 10, &QNode::poseCallback,this);注：此处与命令行方式的定义有所不同，
- 回调函数前要加上“&”和“类名”
- 回调函数后面再加上“this”
3.创建回调函数
void QNode::poseCallback(const turtlesim::Pose::ConstPtr& msg)
{
// 将接收到的消息打印出来
std::stringstream ss;
ss<<"x:"<<msg->x<<" y:"<<msg->y;
log(Info,"Turtle pose:"+ss.str());
}回调函数中对话题进行处理，通过自带的log函数输出
总结：
- 创建订阅者
- 定义回调函数
四、键盘控制
void ros_qt_demo::MainWindow::on_pushButton_W_pressed()
{
int x=ui.label_6->text().toInt();
if(x==0) x=20;
ui.horizontalSlider->setValue(x);
}
void ros_qt_demo::MainWindow::on_pushButton_W_released()
{
ui.horizontalSlider->setValue(0);
}
void ros_qt_demo::MainWindow::on_pushButton_S_pressed()
{
int x=ui.label_6->text().toInt();
x=0-x;
if(x==0) x=-50;
ui.horizontalSlider->setValue(x);
}
void ros_qt_demo::MainWindow::on_pushButton_S_released()
{
ui.horizontalSlider->setValue(0);
}
void ros_qt_demo::MainWindow::on_pushButton_A_pressed()
{
int x=ui.label_7->text().toInt();
if(x==0) x=50;
ui.horizontalSlider_2->setValue(x);
}
void ros_qt_demo::MainWindow::on_pushButton_A_released()
{
ui.horizontalSlider_2->setValue(0);
}
void ros_qt_demo::MainWindow::on_pushButton_D_pressed()
{
int x=ui.label_7->text().toInt();
x=0-x;
if(x==0) x=-50;
ui.horizontalSlider_2->setValue(x);
}
void ros_qt_demo::MainWindow::on_pushButton_D_released()
{
ui.horizontalSlider_2->setValue(0);
}由于发布话题和ui分别写在两个不同的类中，需要通过信号与槽机制建立连接。
1.main_window.hpp
signals:
void getlinevelocity(int velocity);
void getlangular(int velocity);2.qnode.hpp
public slots:
void on_getlinevelocity(int velocity);
void on_getlangular(int velocity);3.连接
connect(this,SIGNAL(getlinevelocity(int)),&qnode,SLOT(on_getlinevelocity(int)));
connect(this,SIGNAL(getlangular(int)),&qnode,SLOT(on_getlangular(int)));五、运行终端命令
void ros_qt_demo::MainWindow::on_pushButton_3_clicked()
{
QProcess *process=new QProcess;
//打开终端
process->start("bash");
//写入命令
process->write(ui.textEdit->toPlainText().toLocal8Bit()+'n');
ui.textBrowser->append(process->readAll().data());
}
注：process->write(ui.textEdit->toPlainText().toLocal8Bit()+'n');中‘n’不可省略
六、案例源码
1.main_window.hpp
/**
* @file /include/ros_qt_demo/main_window.hpp
*
* @brief Qt based gui for ros_qt_demo.
*
* @date November 2010
**/
#ifndef ros_qt_demo_MAIN_WINDOW_H
#define ros_qt_demo_MAIN_WINDOW_H
/*****************************************************************************
** Includes
*****************************************************************************/
#include <QtWidgets/QMainWindow>
#include "ui_main_window.h"
#include "qnode.hpp"
/*****************************************************************************
** Namespace
*****************************************************************************/
namespace ros_qt_demo {
/*****************************************************************************
** Interface [MainWindow]
*****************************************************************************/
/**
* @brief Qt central, all operations relating to the view part here.
*/
class MainWindow : public QMainWindow {
Q_OBJECT
signals:
void getlinevelocity(int velocity);
void getlangular(int velocity);
public:
MainWindow(int argc, char** argv, QWidget *parent = 0);
~MainWindow();
void ReadSettings(); // Load up qt program settings at startup
void WriteSettings(); // Save qt program settings when closing
void closeEvent(QCloseEvent *event); // Overloaded function
void showNoMasterMessage();
public Q_SLOTS:
/******************************************
** Auto-connections (connectSlotsByName())
*******************************************/
void on_actionAbout_triggered();
void on_button_connect_clicked(bool check );
void on_checkbox_use_environment_stateChanged(int state);
/******************************************
** Manual connections
*******************************************/
void updateLoggingView(); // no idea why this can't connect automatically
private slots:
void on_horizontalSlider_valueChanged(int value);
void on_horizontalSlider_2_valueChanged(int value);
void on_pushButton_clicked();
void on_pushButton_2_clicked();
void on_pushButton_W_pressed();
void on_pushButton_W_released();
void on_pushButton_S_pressed();
void on_pushButton_S_released();
void on_pushButton_A_pressed();
void on_pushButton_A_released();
void on_pushButton_D_pressed();
void on_pushButton_D_released();
void on_pushButton_3_clicked();
private:
Ui::MainWindowDesign ui;
QNode qnode;
};
} // namespace ros_qt_demo
#endif // ros_qt_demo_MAIN_WINDOW_H
2.main_window.cpp
/**
* @file /src/main_window.cpp
*
* @brief Implementation for the qt gui.
*
* @date February 2011
**/
/*****************************************************************************
** Includes
*****************************************************************************/
#include <QtGui>
#include <QMessageBox>
#include <iostream>
#include "../include/ros_qt_demo/main_window.hpp"
#include<qprocess.h>
/*****************************************************************************
** Namespaces
*****************************************************************************/
namespace ros_qt_demo {
using namespace Qt;
/*****************************************************************************
** Implementation [MainWindow]
*****************************************************************************/
MainWindow::MainWindow(int argc, char** argv, QWidget *parent)
: QMainWindow(parent)
, qnode(argc,argv)
{
ui.setupUi(this); // Calling this incidentally connects all ui's triggers to on_...() callbacks in this class.
QObject::connect(ui.actionAbout_Qt, SIGNAL(triggered(bool)), qApp, SLOT(aboutQt())); // qApp is a global variable for the application
ReadSettings();
setWindowIcon(QIcon(":/images/icon.png"));
ui.tab_manager->setCurrentIndex(0); // ensure the first tab is showing - qt-designer should have this already hardwired, but often loses it (settings?).
QObject::connect(&qnode, SIGNAL(rosShutdown()), this, SLOT(close()));
/*********************
** Logging
**********************/
ui.view_logging->setModel(qnode.loggingModel());
QObject::connect(&qnode, SIGNAL(loggingUpdated()), this, SLOT(updateLoggingView()));
/*********************
** Auto Start
**********************/
if ( ui.checkbox_remember_settings->isChecked() ) {
on_button_connect_clicked(true);
}
connect(this,SIGNAL(getlinevelocity(int)),&qnode,SLOT(on_getlinevelocity(int)));
connect(this,SIGNAL(getlangular(int)),&qnode,SLOT(on_getlangular(int)));
}
MainWindow::~MainWindow() {}
/*****************************************************************************
** Implementation [Slots]
*****************************************************************************/
void MainWindow::showNoMasterMessage() {
QMessageBox msgBox;
msgBox.setText("Couldn't find the ros master.");
msgBox.exec();
close();
}
/*
* These triggers whenever the button is clicked, regardless of whether it
* is already checked or not.
*/
void MainWindow::on_button_connect_clicked(bool check ) {
if ( ui.checkbox_use_environment->isChecked() ) {
if ( !qnode.init() ) {
showNoMasterMessage();
} else {
ui.button_connect->setEnabled(false);
}
} else {
if ( ! qnode.init(ui.line_edit_master->text().toStdString(),
ui.line_edit_host->text().toStdString()) ) {
showNoMasterMessage();
} else {
ui.button_connect->setEnabled(false);
ui.line_edit_master->setReadOnly(true);
ui.line_edit_host->setReadOnly(true);
ui.line_edit_topic->setReadOnly(true);
}
}
}
void MainWindow::on_checkbox_use_environment_stateChanged(int state) {
bool enabled;
if ( state == 0 ) {
enabled = true;
} else {
enabled = false;
}
ui.line_edit_master->setEnabled(enabled);
ui.line_edit_host->setEnabled(enabled);
//ui.line_edit_topic->setEnabled(enabled);
}
/*****************************************************************************
** Implemenation [Slots][manually connected]
*****************************************************************************/
/**
* This function is signalled by the underlying model. When the model changes,
* this will drop the cursor down to the last line in the QListview to ensure
* the user can always see the latest log message.
*/
void MainWindow::updateLoggingView() {
ui.view_logging->scrollToBottom();
}
/*****************************************************************************
** Implementation [Menu]
*****************************************************************************/
void MainWindow::on_actionAbout_triggered() {
QMessageBox::about(this, tr("About ..."),tr("<h2>PACKAGE_NAME Test Program 0.10</h2><p>Copyright Yujin Robot</p><p>This package needs an about description.</p>"));
}
/*****************************************************************************
** Implementation [Configuration]
*****************************************************************************/
void MainWindow::ReadSettings() {
QSettings settings("Qt-Ros Package", "ros_qt_demo");
restoreGeometry(settings.value("geometry").toByteArray());
restoreState(settings.value("windowState").toByteArray());
QString master_url = settings.value("master_url",QString("http://192.168.1.2:11311/")).toString();
QString host_url = settings.value("host_url", QString("192.168.1.3")).toString();
//QString topic_name = settings.value("topic_name", QString("/chatter")).toString();
ui.line_edit_master->setText(master_url);
ui.line_edit_host->setText(host_url);
//ui.line_edit_topic->setText(topic_name);
bool remember = settings.value("remember_settings", false).toBool();
ui.checkbox_remember_settings->setChecked(remember);
bool checked = settings.value("use_environment_variables", false).toBool();
ui.checkbox_use_environment->setChecked(checked);
if ( checked ) {
ui.line_edit_master->setEnabled(false);
ui.line_edit_host->setEnabled(false);
//ui.line_edit_topic->setEnabled(false);
}
}
void MainWindow::WriteSettings() {
QSettings settings("Qt-Ros Package", "ros_qt_demo");
settings.setValue("master_url",ui.line_edit_master->text());
settings.setValue("host_url",ui.line_edit_host->text());
//settings.setValue("topic_name",ui.line_edit_topic->text());
settings.setValue("use_environment_variables",QVariant(ui.checkbox_use_environment->isChecked()));
settings.setValue("geometry", saveGeometry());
settings.setValue("windowState", saveState());
settings.setValue("remember_settings",QVariant(ui.checkbox_remember_settings->isChecked()));
}
void MainWindow::closeEvent(QCloseEvent *event)
{
WriteSettings();
QMainWindow::closeEvent(event);
}
} // namespace ros_qt_demo
void ros_qt_demo::MainWindow::on_horizontalSlider_valueChanged(int value)
{
ui.label_6->setText(QString::number(value));
emit getlinevelocity(value);
}
void ros_qt_demo::MainWindow::on_horizontalSlider_2_valueChanged(int value)
{
ui.label_7->setText(QString::number(value));
emit getlangular(value);
}
void ros_qt_demo::MainWindow::on_pushButton_clicked()
{
ui.horizontalSlider->setValue(0);
}
void ros_qt_demo::MainWindow::on_pushButton_2_clicked()
{
ui.horizontalSlider_2->setValue(0);
}
void ros_qt_demo::MainWindow::on_pushButton_W_pressed()
{
int x=ui.label_6->text().toInt();
if(x==0) x=20;
ui.horizontalSlider->setValue(x);
}
void ros_qt_demo::MainWindow::on_pushButton_W_released()
{
ui.horizontalSlider->setValue(0);
}
void ros_qt_demo::MainWindow::on_pushButton_S_pressed()
{
int x=ui.label_6->text().toInt();
x=0-x;
if(x==0) x=-50;
ui.horizontalSlider->setValue(x);
}
void ros_qt_demo::MainWindow::on_pushButton_S_released()
{
ui.horizontalSlider->setValue(0);
}
void ros_qt_demo::MainWindow::on_pushButton_A_pressed()
{
int x=ui.label_7->text().toInt();
if(x==0) x=50;
ui.horizontalSlider_2->setValue(x);
}
void ros_qt_demo::MainWindow::on_pushButton_A_released()
{
ui.horizontalSlider_2->setValue(0);
}
void ros_qt_demo::MainWindow::on_pushButton_D_pressed()
{
int x=ui.label_7->text().toInt();
x=0-x;
if(x==0) x=-50;
ui.horizontalSlider_2->setValue(x);
}
void ros_qt_demo::MainWindow::on_pushButton_D_released()
{
ui.horizontalSlider_2->setValue(0);
}
void ros_qt_demo::MainWindow::on_pushButton_3_clicked()
{
QProcess *process=new QProcess;
//打开终端
process->start("bash");
//写入命令
process->write(ui.textEdit->toPlainText().toLocal8Bit()+'n');
ui.textBrowser->append(process->readAll().data());
}
3.qnode.hpp
/**
* @file /include/ros_qt_demo/qnode.hpp
*
* @brief Communications central!
*
* @date February 2011
**/
/*****************************************************************************
** Ifdefs
*****************************************************************************/
#ifndef ros_qt_demo_QNODE_HPP_
#define ros_qt_demo_QNODE_HPP_
/*****************************************************************************
** Includes
*****************************************************************************/
// To workaround boost/qt4 problems that won't be bugfixed. Refer to
// https://bugreports.qt.io/browse/QTBUG-22829
#ifndef Q_MOC_RUN
#include <ros/ros.h>
#endif
#include <string>
#include <QThread>
#include <QStringListModel>
#include <geometry_msgs/Twist.h>
#include "turtlesim/Pose.h"
/*****************************************************************************
** Namespaces
*****************************************************************************/
namespace ros_qt_demo {
/*****************************************************************************
** Class
*****************************************************************************/
class QNode : public QThread {
Q_OBJECT
public:
QNode(int argc, char** argv );
virtual ~QNode();
bool init();
bool init(const std::string &master_url, const std::string &host_url);
void run();
/*********************
** Logging
**********************/
enum LogLevel {
Debug,
Info,
Warn,
Error,
Fatal
};
QStringListModel* loggingModel() { return &logging_model; }
void log( const LogLevel &level, const std::string &msg);
int linevelocity=0;
int angular=0;
Q_SIGNALS:
void loggingUpdated();
void rosShutdown();
private:
int init_argc;
char** init_argv;
//ros::Publisher chatter_publisher;
ros::Publisher turtle_vel_pub;
ros::Subscriber pose_sub;
void poseCallback(const turtlesim::Pose::ConstPtr& msg);
QStringListModel logging_model;
public slots:
void on_getlinevelocity(int velocity);
void on_getlangular(int velocity);
};
} // namespace ros_qt_demo
#endif /* ros_qt_demo_QNODE_HPP_ */
4.qnode.cpp
/**
* @file /src/qnode.cpp
*
* @brief Ros communication central!
*
* @date February 2011
**/
/*****************************************************************************
** Includes
*****************************************************************************/
#include <ros/ros.h>
#include <ros/network.h>
#include <string>
#include <std_msgs/String.h>
#include <sstream>
#include "../include/ros_qt_demo/qnode.hpp"
#include<qdebug.h>
/*****************************************************************************
** Namespaces
*****************************************************************************/
namespace ros_qt_demo {
/*****************************************************************************
** Implementation
*****************************************************************************/
QNode::QNode(int argc, char** argv ) :
init_argc(argc),
init_argv(argv)
{}
QNode::~QNode() {
if(ros::isStarted()) {
ros::shutdown(); // explicitly needed since we use ros::start();
ros::waitForShutdown();
}
wait();
}
bool QNode::init()
{
//初始化ROS节点“ros_qt_demo”
ros::init(init_argc,init_argv,"ros_qt_demo");
//检测ROS节点是否打开
if ( ! ros::master::check() )
{
return false;
}
ros::start(); // explicitly needed since our nodehandle is going out of scope.
//创建句柄
ros::NodeHandle n;
// Add your ros communications here.
// chatter_publisher = n.advertise<std_msgs::String>("chatter", 1000);
turtle_vel_pub = n.advertise<geometry_msgs::Twist>("/turtle1/cmd_vel", 10);
pose_sub = n.subscribe("/turtle1/pose", 10, &QNode::poseCallback,this);
//调用run（）
start();
return true;
}
bool QNode::init(const std::string &master_url, const std::string &host_url) {
std::map<std::string,std::string> remappings;
remappings["__master"] = master_url;
remappings["__hostname"] = host_url;
ros::init(remappings,"ros_qt_demo");
if ( ! ros::master::check() ) {
return false;
}
ros::start(); // explicitly needed since our nodehandle is going out of scope.
ros::NodeHandle n;
// Add your ros communications here.
// chatter_publisher = n.advertise<std_msgs::String>("chatter", 1000);
turtle_vel_pub = n.advertise<geometry_msgs::Twist>("/turtle1/cmd_vel", 10);
pose_sub = n.subscribe("/turtle1/pose", 10, &QNode::poseCallback,this);
start();
return true;
}
void QNode::poseCallback(const turtlesim::Pose::ConstPtr& msg)
{
// 将接收到的消息打印出来
std::stringstream ss;
ss<<"x:"<<msg->x<<" y:"<<msg->y;
log(Info,"Turtle pose:"+ss.str());
}
void QNode::run() {
ros::Rate loop_rate(1);
int count = 0;
while ( ros::ok() ) {
geometry_msgs::Twist vel_msg;
vel_msg.linear.x = linevelocity*0.01;
vel_msg.angular.z = angular*0.01;
// 发布消息
turtle_vel_pub.publish(vel_msg);
// std_msgs::String msg;
// std::stringstream ss;
// ss << "hello world " << count;
// msg.data = ss.str();
// chatter_publisher.publish(msg);
// log(Info,std::string("I sent: ")+msg.data);
ros::spinOnce();
loop_rate.sleep();
++count;
}
std::cout << "Ros shutdown, proceeding to close the gui." << std::endl;
Q_EMIT rosShutdown(); // used to signal the gui for a shutdown (useful to roslaunch)
}
void QNode::on_getlinevelocity(int velocity)
{
linevelocity=velocity;
}
void QNode::on_getlangular(int velocity)
{
angular=velocity;
}
void QNode::log( const LogLevel &level, const std::string &msg) {
logging_model.insertRows(logging_model.rowCount(),1);
std::stringstream logging_model_msg;
switch ( level ) {
case(Debug) : {
ROS_DEBUG_STREAM(msg);
logging_model_msg << "[DEBUG] [" << ros::Time::now() << "]: " << msg;
break;
}
case(Info) : {
ROS_INFO_STREAM(msg);
logging_model_msg << "[INFO] [" << ros::Time::now() << "]: " << msg;
break;
}
case(Warn) : {
ROS_WARN_STREAM(msg);
logging_model_msg << "[INFO] [" << ros::Time::now() << "]: " << msg;
break;
}
case(Error) : {
ROS_ERROR_STREAM(msg);
logging_model_msg << "[ERROR] [" << ros::Time::now() << "]: " << msg;
break;
}
case(Fatal) : {
ROS_FATAL_STREAM(msg);
logging_model_msg << "[FATAL] [" << ros::Time::now() << "]: " << msg;
break;
}
}
QVariant new_row(QString(logging_model_msg.str().c_str()));
logging_model.setData(logging_model.index(logging_model.rowCount()-1),new_row);
Q_EMIT loggingUpdated(); // used to readjust the scrollbar
}
} // namespace ros_qt_demo
最后
以上就是英勇马里奥为你收集整理的ROS下基于Qt的人机交互开发（四）在Qt中发布和订阅话题前言一、创建节点二、发布话题三、订阅话题四、键盘控制五、运行终端命令六、案例源码的全部内容，希望文章能够帮你解决ROS下基于Qt的人机交互开发（四）在Qt中发布和订阅话题前言一、创建节点二、发布话题三、订阅话题四、键盘控制五、运行终端命令六、案例源码所遇到的程序开发问题。
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