qt 信号与槽初步使用

来源：互联网发布：百川江湖淘宝编辑：程序博客网时间：2024/05/22 13:57

简单使用，Teacher有了任务后，分派给Student，Student完成后，通知Teacher。

#ifndef CTEACHER_H#define CTEACHER_H#include <QObject>class CTeacher : public QObject{    Q_OBJECTpublic:    explicit CTeacher(const QString &name,QObject *parent = 0);    void taskFromB(QString task,int idx);signals:    void dispatchTask(QString &taskName,int ibegin,int icount);public slots:    void taskCompleted(QString &taskName,QString &whoDid);private:    QString _myName;};#endif // CTEACHER_H

#include "cteacher.h"#include <QDebug>CTeacher::CTeacher(const QString &name,QObject *parent) :    _myName(name),    QObject(parent){}void CTeacher::taskCompleted(QString &taskName, QString &whoDid){    qDebug()<<_myName<<" received message - "<<"task:"<<taskName<<" completed by "<<whoDid;}void CTeacher::taskFromB(QString task,int idx){    emit dispatchTask(task,idx,100);}

Teacher使用taskFromB得到任务并分派给Student，并在收到Student完成的消息后打印相关信息。

#ifndef CSTUDENT_H#define CSTUDENT_H#include <QObject>class CStudent : public QObject{    Q_OBJECTpublic:    explicit CStudent(const QString& name,QObject *parent = 0);    int SetFavor(int i) { _ifavor = i;return _ifavor;}    void taskDone(){emit taskCompleted(_taskName,_myName);}signals:    void taskCompleted(QString &taskName,QString &whoDid);public slots:    void gotTask(QString &taskName,int ibegin, int icount);private:    QString _myName,_taskName;    int _ifavor;};#endif // CSTUDENT_H

#include "cstudent.h"#include <QDebug>CStudent::CStudent(const QString &name,QObject *parent) :    QObject(parent),    _myName(name),    _ifavor(0){}void CStudent::gotTask(QString &taskName, int ibegin, int icount){    if(ibegin != _ifavor)        return ;    _taskName = taskName;    qDebug()<<_myName<<" got task("<<_taskName<<" begin:"<<ibegin<<" count:"<<icount<<")";}

Teacher分派消息后，Student在gotTask中获得任务，再调用taskDone表示任务完成。

#include <QCoreApplication>#include "cteacher.h"#include "cstudent.h"int main(int argc, char *argv[]){    QCoreApplication a(argc, argv);    CTeacher kakaxi("kakaxi");    CStudent naliduo("naliduo"),sekei("sekei");    naliduo.SetFavor(1);    sekei.SetFavor(2);    QObject::connect(&kakaxi,SIGNAL(dispatchTask(QString&,int,int)),&naliduo,SLOT(gotTask(QString&,int,int)));    QObject::connect(&kakaxi,SIGNAL(dispatchTask(QString&,int,int)),&sekei,SLOT(gotTask(QString&,int,int)));    QObject::connect(&naliduo,SIGNAL(taskCompleted(QString&,QString&)),&kakaxi,SLOT(taskCompleted(QString&,QString&)));    QObject::connect(&sekei,SIGNAL(taskCompleted(QString&,QString&)),&kakaxi,SLOT(taskCompleted(QString&,QString&)));    kakaxi.taskFromB(QString("AAA"),1);    kakaxi.taskFromB(QString("BBB"),2);    sekei.taskDone();    naliduo.taskDone();    return a.exec();}

创建一个Teacher、两个Student，并联接相应的信号与槽。Teacher的一个信号联接了两个Student，两个Student的信号联接了同一个Teacher。

只是简单演示。

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