信号和槽机制解析

https://blog.51cto.com/9291927/2070398

 

#ifndef MYOBJECT_H
#define MYOBJECT_H

#include <QObject>
#include <QString>
#include <QDebug>

class MyObject: public QObject
{
    Q_OBJECT
    Q_PROPERTY(int age READ age  WRITE setAge NOTIFY ageChanged)
    Q_PROPERTY(int score READ score  WRITE setScore NOTIFY scoreChanged)
    Q_PROPERTY(Level level READ level WRITE setLevel)
    Q_CLASSINFO("Version","1.0")
public:
    enum Level
    {
        Basic = 1,
        Middle,
        Advanced,
        Master
    };
    Q_ENUM(Level)
protected:
    QString m_name;
    Level m_level;
    int m_age;
    int m_score;
    void setLevel(const int& score)
    {
        if(score <= 60)
        {
            m_level = Basic;
        }
        else if(score < 100)
        {
            m_level = Middle;
        }
        else if(score < 150)
        {
            m_level = Advanced;
        }
        else
        {
            m_level = Master;
        }
    }
public:
    explicit MyObject(QString name, QObject *parent = 0):QObject(parent)
    {
        m_name = name;
        setObjectName(m_name);
        connect(this, SIGNAL(ageChanged(int)), this, SLOT(onAgeChanged(int)));
        connect(this, SIGNAL(scoreChanged(int)), this, SLOT(onScoreChanged(int)));
    }

    int age()const
    {
        return m_age;
    }

    void setAge(const int& age)
    {
        m_age = age;
        emit ageChanged(m_age);
    }

    int score()const
    {
        return m_score;
    }

    void setScore(const int& score)
    {
        m_score = score;
        setLevel(m_score);
        emit scoreChanged(m_score);
    }

    Level level()const
    {
        return m_level;
    }

    void setLevel(const Level& level)
    {
        m_level = level;
    }
signals:
    void ageChanged(int age);
    void scoreChanged(int score);
public slots:
     void onAgeChanged(int age)
     {
         qDebug() << "age changed:" << age;
     }
     void onScoreChanged(int score)
     {
         qDebug() << "score changed:" << score;
     }

};

#endif // MYOBJECT_H

main.cpp

#include <QCoreApplication>
#include "myobject.h"
int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);

    MyObject ob("myobject");

    //设置属性age
    ob.setProperty("age", QVariant(30));
    qDebug() << "age: " << ob.age();
    qDebug() << "property age: " << ob.property("age").toInt();

    //设置属性score
    ob.setProperty("score", QVariant(90));
    qDebug() << "score: " << ob.score();
    qDebug() << "property score: " << ob.property("score").toInt();

    qDebug() << "Level: " << ob.level();
    ob.setProperty("level", 4);
    qDebug() << "level: " << ob.level();
    qDebug() << "Property level: " << ob.property("level").toInt();

    //内省intropection,运行时查询对象信息
    qDebug() << "object name: " << ob.objectName();
    qDebug() << "class name: " << ob.metaObject()->className();
    qDebug() << "isWidgetType: " << ob.isWidgetType();
    qDebug() << "inherit: " << ob.inherits("QObject");

    return a.exec();
}

 

结果：