QObject::startTimer: Timers cannot be started from another thread [使用自定义信号与曹函数来解决在子线程中不能调用QTimer定时器]

清疚 2022-10-05 08:55 187阅读 0赞

#        使用自定义信号与曹函数来解决在子线程中不能调用QTimer定时器 #

报错：

QObject::startTimer: Timers cannot be started from another thread

（此方法区别与其他博主给的方案，其他博主给的方案是在子线程中创建QTimer定时器，我的方法是用信号和槽来处理，此方法的好处是可以在子线程中开启定时器，在其他线程或主线程中关闭定时器）

如何在ros的 SimpleActionClient的回调函数子线程中调用主线程创建的QTimer定时器

实例 1 ：

#ifndef VISUALORIENTATION_CarStartServuceClient_H
    #define VISUALORIENTATION_CarStartServuceClient_H
    
    #include <Eigen/Geometry>
    #include <opencv/cxeigen.hpp>
    #include <opencv2/opencv.hpp>
    #include <QtWidgets>
    #include <QDebug>
    #include <QComboBox>
    #include <QHBoxLayout>
    #include <QVBoxLayout>
    #include "ros/ros.h"
    #include <actionlib/client/simple_action_client.h>
    #include "move_base_msgs/MoveBaseAction.h"
    #include "move_base_msgs/MoveBaseGoal.h"
    #include <ros/package.h>
    #include <iostream>
    #include <math.h>
    #include <qrcode_srvs/qRcode.h>
    #include "qrcode_msg/qRcode_msg.h"
    #include "geometry_msgs/PoseWithCovarianceStamped.h"
    #include <visualization_msgs/Marker.h>
    #include <std_msgs/String.h>
    #include <QtSql/QSqlDatabase>
    #include <QtSql/QSqlQuery>
    #include <QtSql/QSqlRecord>
    #include <QTimer>
    #include "utils/data.h"
    #include "disinfect_msg/gono_msg.h"
    /**
     * 发送路点目标点
     * 苏凯
     * 2021-03-26
     */
    using namespace std;
    using namespace cv;
    
    class CarStartServuceClient: public QWidget {
    Q_OBJECT
    public:
        CarStartServuceClient(ros::NodeHandle *node, QWidget *parent = nullptr);
    
        ~CarStartServuceClient() ;
    private:
        ros::NodeHandle *node;
        ros::Subscriber subscriber;
      
        //等待5分钟执行下一条送餐指令： 1000*60*5
        QTimer* waitGoalTimer;
        //move_base 控制小车运动
     //   actionlib::SimpleActionClient<move_base_msgs::MoveBaseAction> ac_client;
        actionlib::SimpleActionClient<move_base_msgs::MoveBaseAction> *ac_client;
    private:
    
          //SimpleActionClient 回调函数
        void done_cb(const actionlib::SimpleClientGoalState &state,
                     const move_base_msgs::MoveBaseResult::ConstPtr &result);
    //发送SimpleActionClient
    void CarStartServuceClient::move_to_goal(double xGoal,double yGoal,double z,double w)；
    //自定义信号与槽
    signals:
        void backwaitGoalWithTimeSignal();
    protected slots:
        void sendwaitGoalWithTimeSignal();
    
    };
    
    #endif //VISUALORIENTATION_CarStartServuceClient_H

#include "carStartServuceClient.h"
    #include "utils/Rotation3DUtils.h"
    #include "utils/data.h"
    #include <thread>
    
    /**
     * 发送目标点
     * 苏凯
     * 2021-03-26
     */
    CarStartServuceClient::CarStartServuceClient(ros::NodeHandle *node, QWidget *parent): QWidget(parent),node(node)  {
    
      
    initWidgets();
    bindSignal();
    initRosCommunication();
    }
    
    CarStartServuceClient::~CarStartServuceClient(){
    
    };
    
    
    
    void CarStartServuceClient::initWidgets() {
        //等待5分钟执行下一条送餐指令： 1000*60*5
        waitGoalTimer= new QTimer(this);
        waitGoalTimer->setInterval(1000*60*5);
    }
    void CarStartServuceClient::bindSignal() {
     
        //等待5分钟执行下一条送餐指令： 1000*60*5
        connect(waitGoalTimer, &QTimer::timeout, this, &CarStartServuceClient::waitGoalWithTime);
    
        //自定义信号与曹, 调用waitGoalTimer 待5分钟执行下一条送餐指令： 1000*60*5 [处理多线程中不能调用QTimer定时器的问题]
    connect(this,SIGNAL(backwaitGoalWithTimeSignal()),this,SLOT(sendwaitGoalWithTimeSignal()));
    }
    
    //自定义曹 调用waitGoalTimer 待5分钟执行下一条送餐指令： 1000*60*5 [处理多线程中不能调用QTimer定时器的问题]
    void CarStartServuceClient::sendwaitGoalWithTimeSignal(){
        //等待5分钟执行下一条送餐指令： 1000*60*5
        waitGoalTimer->start();
        cout << "多线程 sendwaitGoalWithTimeSignal！"<< endl;
    }
    
    //ros通讯
    void CarStartServuceClient::initRosCommunication() {
        ac_client = new actionlib::SimpleActionClient<move_base_msgs::MoveBaseAction>(*node,"move_base");
    
    }
    
    
    //等待5分钟执行下一条送餐指令： 1000*60*5
    void CarStartServuceClient::waitGoalWithTime(){
        waitGoalTimer->stop();
        isGoal=true;
        cout << "等待5分钟执行下一条送餐指令"<< endl;
    }
    
    
    //SimpleActionClient 回调函数【此函数是在子线程中运行的，这个函数里不能直接操作主线程创建的QTimer定时器，需要通过自定义的信号与曹来间接的调用定时器】
    void CarStartServuceClient::done_cb(const actionlib::SimpleClientGoalState &state,
                                        const move_base_msgs::MoveBaseResult::ConstPtr &result){
    
        if (state==actionlib::SimpleClientGoalState::SUCCEEDED){//服务端setSucced
      ROS_INFO_STREAM("成功到达—new！");
            cout << "成功到达—new！"<< endl;
            //【子线程中通过自定义的信号与曹间接的调用定时器】
            emit  backwaitGoalWithTimeSignal();
            
        }else if(state==actionlib::SimpleClientGoalState::ABORTED){//setAborted
           ROS_INFO_STREAM("服务出错—new!");
            cout << "服务出错—new!"<< endl;
          
        }else if(state==actionlib::SimpleClientGoalState::PREEMPTED){//setAborted
            ROS_INFO_STREAM("取消—new!");
            cout << "取消—new!"<< endl;
        }
    
    
    }
    
    //发送SimpleActionClient
    void CarStartServuceClient::move_to_goal(double xGoal,double yGoal,double z,double w){
    
        while (not ac_client->waitForServer())
            cout << "等待move_base actionserver启动" << endl;
    
        move_base_msgs::MoveBaseGoal goal;
        //指定地图参考系
        goal.target_pose.header.frame_id = "map";
        goal.target_pose.header.stamp = ros::Time::now();
        //移动目标设定位姿 xyz和四元数
        goal.target_pose.pose.position.x = xGoal;
        goal.target_pose.pose.position.y =yGoal;
        goal.target_pose.pose.position.z= 0;
    
        goal.target_pose.pose.orientation.x = 0.0;
        goal.target_pose.pose.orientation.y = 0.0;
        goal.target_pose.pose.orientation.z = z;
        goal.target_pose.pose.orientation.w = w;
        cout << "发送目标到actionserver ..." << endl;
    //发送带有回调函数的SimpleActionClient
        ac_client->sendGoal(goal,boost::bind(&CarStartServuceClient::done_cb,this,_1,_2),boost::bind(&CarStartServuceClient::active_cb,this),boost::bind(&CarStartServuceClient::feedback_cb,this,_1));
    
    }

实例 2 ：自定义信号和槽函数简单示例

class MyMainWindow : public QWidget   
    { 
    Q_OBJECT 
    public: 
    void MyMainWindow();   
    void SetNum(int); 
    signals:    
    void backwaitGoalWithTimeSignal(int);     //自定义信号
    public slots: 
    void sendwaitGoalWithTimeSignal(int);        //自定义槽
    };

//调用函数
    void MyMainWindow::SetNum(int num) 
    { 
    //调用自定义信号执行自定义槽函数
    emit backwaitGoalWithTimeSignal(num); 
    } 
    } 
    
    //自定义槽函数
    void MyMainWindow::sendwaitGoalWithTimeSignal(int num) 
    { 
       cout<<num<<endl;
    }