simple-qobject-factory.c

#include <QObject>
#include <QDebug>

class FactoryBase
{
public:
    virtual QObject* create() = 0;
};

QMap<QString, FactoryBase*> factoryMap;

template<class T>
class Factory : public FactoryBase
{
public:
    Factory() {
        factoryMap.insert(T::staticMetaObject.className(), this);
    }

    virtual QObject* create() {
        return new T;
    }
};

class CA : public QObject
{
    Q_OBJECT
public:
    explicit CA(QObject* parent = 0) : QObject(parent) {}
    Q_INVOKABLE void printSomething() { qDebug() << "This is CA"; }
};

Factory<CA> caFactory;

class CB : public QObject
{
    Q_OBJECT
public:
    explicit CB(QObject* parent = 0) : QObject(parent) {}
    Q_INVOKABLE void printSomething() { qDebug() << "This is CB"; }
};

Factory<CB> CBFactory;

int main(int argc, char* argv[]) {
    Q_UNUSED(argc);
    Q_UNUSED(argv);

    QObject* obj1 = factoryMap["CA"]->create();
    QMetaObject::invokeMethod(obj1, "printSomething");
    QObject* obj2 = factoryMap["CB"]->create();
    QMetaObject::invokeMethod(obj2, "printSomething");

    delete obj1;
    delete obj2;

    return 0;
}

#include "main.moc"