Exposing a dynamic set of properties to Qml

[Smatcher]

Hello !

I'm a trying to do the following with Qml :
My project is an application with a Qml interface around some non-Qt modules (loaded at runtime).
The application and the modules communicate through PropertyContainers which are dictionaries of abstract data (the equivalent of a QVariantMap but with a different implementation).
I want to expose these dictionaries to Qml, without writing C++ code specific to the keys in these dictionaries (new modules and qml interfaces must be developed without rebuilding the application).

My first implementation relies on QAbstractListModel. I can attach any of these PropertyContainers to the model and a Qml ListView will display a simple property editor. This implementation has some limitations: it only works for Qml Items meant to use a model (Repeater, ListView) and it doesn't allow binding.

Ideally I would like to have each dictionary entry available as a property from Qml.
For example a PropertyContainer with the following properties:

• text = "Hello World"
• color = "red"
• width = 100

Would be wrapped in a "props" QObject which can be accessed from Qml like this

Rectangle {
    color: props.color
    width: props.width
    TextField {
        text: props.text
    }
}

Since using QObject's dynamic properties with the function setProperty() doesn't expose the properties to Qml. I am contemplating writing a wrapper QObject class implementing its own setters/getters and using QMetaObjectBuilder to generate a per instance metaObject listing all the dictionary keys as properties.

Building my own metaObject seems like overkill, risky and prone to cause a lot of problems when updating Qt so I would like to know a few things first.

• Is there a simpler way to do what I'm trying to do?
• Why is QMetaObjectBuilder not part of the public API? Is it really a bad idea to write code using this class?
• Why is it that dynamic properties aren't available from QML? If I'm not mistaken they seem to be available from QScript. Will this change at some point?