Possible to override toString in Javascript for a QObject-derived class?

[mjmvisser]

I've exposed a property from C++ called "paths". Currently, this property returns a const QStringList, which is nicely mapped to a Javascript array of strings. I now need "paths" to support sequences of frames, so each "path" now has additional metadata (the frame list), which may also involve QObject-derived classes. I'd like this new object to still behave like a string, but expose additional properties.

For example, a sequence of 4 frames:
@["/foo/bar.0001.exr",
"/foo/bar.0002.exr",
"/foo/bar.0003.exr",
"/foo/bar.0004.exr"]@

could be represented as an Object with a "toString()" method that returns
@"/foo/bar.d.exr"@

and a "frameList" property that returns
@[1,2,3,4]@

I've tried adding this to the class:

@ Q_INVOKABLE const QString toString() const;@

But it has no effect. :-(

So, currently possible? Good Idea/Bad Idea?

I should mention that I'm somewhat familiar with the qtdeclarative module, so I'd be willing to take a stab at adding this feature myself if given a bit of direction on how to proceed (and if it's not a Bad Idea). I'm using Qt5 from github.

cheers,
-Mark

[chrisadams]

Hi,

Check out the qv8qobjectwrapper.cpp:
static v8::Handlev8::Value ToString(QV8Engine *engine, QObject *object, int, v8::Handlev8::Object)

You can modify that to call the toString() function of object if it exists (eg, via QMetaObject::invokeMethod() after first doing a QMetaObject::property() lookup and determining if it's a function).

Cheers,
Chris.