Invoke QObject constructor at run-time

qmetaobject-newinstance.cpp

#include <iostream>
#include <QString>
#include <QMetaObject>
#include <QMetaType>
#include <QObject>
#include <QMetaMethod>
#include "TestObject.h"
int main( int , char** ) {
    const QMetaObject* mo = &TestObject::staticMetaObject;
    TestObject* to = qobject_cast< TestObject* >( mo->newInstance( Q_ARG( QString, "constructed!" ), Q_ARG( QObject*, 0 )  ) ) ;
    std::cout << qPrintable( to->getText() ) << std::endl;
    return 0;
}

TestObject.h

// use with qmetaobject-newinstance.cpp

#include <iostream>
#include <QObject>
#include <QString>
#include <QVariantMap>
#include <QVariantList>
#include <QList>
#include <QVector>

class TestObject : public QObject {
    Q_OBJECT
public:
    Q_INVOKABLE TestObject( QObject* parent = 0 ) : QObject( parent ) {}
    Q_INVOKABLE TestObject( const QString& astring, QObject* parent ) : QObject( parent ), text_( astring ) {}
    Q_INVOKABLE TestObject( const TestObject& other ) : text_( other.text_ ) {}
public slots:
    const QString& getText() const { return text_; }
    void method( const QString& msg ) {
        std::cout << msg.toStdString() << std::endl;
    }
    void emitSignal( const QString& msg ) {
        std::cout << "emitting signal aSignal(" << msg.toStdString() << ")" << std::endl;
        emit aSignal( msg );
    }
    void aSlot( const QString& msg ) {
        std::cout << "aSlot() called with data: " << msg.toStdString() << std::endl;
    }
    QString copyString( const QString& s ) { return s; }
    QVariantMap copyVariantMap( const QVariantMap& vm ) { return vm; }
    QVariantList copyVariantList( const QVariantList& vl ) { return vl; }
    QObject* createObject() {
        TestObject* mo = new TestObject;
        mo->setObjectName( "New Object" );
        return mo; //WARNING: NOT DESTROYED WHEN GARBAGE COLLECTED 
                   //SINCE DEFAULT IS 'QOBJ_NO_DELETE'
    }
    QList< float > copyFloatList( const QList< float >& l ) { return l; }
    QVector< float > copyFloatVector( const QVector< float >& v ) { return v; }
    QList< short > copyShortList( const QList< short >& l ) { return l; }
    QVector< short > copyShortVector( const QVector< short >& v ) { return v; }
signals:
    void aSignal(const QString&);
private:
    QString text_;
};