Reflection on Qt

[tchoninho]

Hi everybody, I would use Reflection on Qt, but I do not know how I can do that. In Java, any object can be instantiated and be called even if unknown. In Qt, I can only do this when I know that this object. Has anyone used Reflection in Qt?

My Object:



class Obj : public QObject
{
Q_OBJECT

public:
Q_INVOKABLE Obj(QObject *parent = 0);
Q_INVOKABLE virtual ~Obj();

Q_INVOKABLE virtual QVariant execute (QList<QVariant> &);
Q_INVOKABLE uint getKey();
};

[squidge]

QMetaObject provides this functionality, you can use it to browse properties and methods of Qt Objects.

http://doc.qt.nokia.com/latest/qmetaobject.html

[scieck]

In Java, any object can be instantiated and be called even if unknown. In Qt, I can only do this when I know that this object


QMetaObject provides this functionality, you can use it to browse properties and methods of Qt Objects.

http://doc.qt.nokia.com/latest/qmetaobject.html

Does QMetaObject provide the functionality of creating and object?

If there is a class called MyClass that extends QObject, is it possible to instantiate it from a QString?
What I mean is, having a QString className("MyClass"); is it possible to instantiate an object of type MyClass?

If an object does not inherit from QObject, then via:


int type = qRegisterMetaType<AClass>();
and
Q_DECLARE_METATYPE(AClass);

Is possible to instantiate an object knowing its int type returned from qRegisterMetaType, but then is there a way to use introspection to query the object about its methods and parameters?

For example in Java is possible to do the following:


Class myclass = Class.forName("MyClass");
Method[] methods = myclass.getMethods();
for (int i = 0; i < methods.length; i++)
{
// methods can also be invoked
System.out.println(methods[i].getName());
}

Is it possible to do something similar using Qt?

Added after 45 minutes:

Ah found it, for anyone interested:

Having the following class:



class MyClass : public QObject
{
Q_OBJECT
public:
Q_INVOKABLE MyClass(QObject *parent = 0);

public:
Q_INVOKABLE void myMethod();
};


Then the following code will print the above class methods:


MyClass *obj = static_cast<MyClass*>(MyClass::staticMetaObject.newInstance());
for (int i = 0; i < obj->metaObject()->methodCount(); i++)
{
QMetaMethod method = obj->metaObject()->method(i);
qDebug() << method.signature();
}

the above will print something like:


destroyed(QObject*)
destroyed()
deleteLater()
_q_reregisterTimers(void*)
myMethod()