QtScript: Properties of the object inherited from QObjectList are not visible from JS

[platon]

I'm trying to expose to JS the audioTracks object which should be accessible from JS as array (audioTracks[index]) and at the same time should have method audioTracks.getTrackById("id").
Here is my object:

class AudioTrackList : public QObject, public QObjectList
    {
        Q_OBJECT
 
    public:
        AudioTrackList(ScriptableIfaceMedia*);
 
        Q_PROPERTY(int length READ size SCRIPTABLE true)
 
        Q_INVOKABLE QObject* getTrackById(QString id);
 
    private:
        ScriptableIfaceMedia* m_impl;
        QScriptEngine         m_engine;
 
    };

class AudioTrackList : public QObject, public QObjectList
    {
        Q_OBJECT

    public:
        AudioTrackList(ScriptableIfaceMedia*);

        Q_PROPERTY(int length READ size SCRIPTABLE true)

        Q_INVOKABLE QObject* getTrackById(QString id);

    private:
        ScriptableIfaceMedia* m_impl;
        QScriptEngine         m_engine;

    };

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The problem is that when I expose the object in the following way:

Q_PROPERTY(QObjectList audioTracks READ audioTracks SCRIPTABLE true)
QObjectList audioTracks();

Q_PROPERTY(QObjectList audioTracks READ audioTracks SCRIPTABLE true)
QObjectList audioTracks();

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QObjectList MediaTracks::audioTracks()
    {
        int i;
 
        QScriptValue rv = m_engine.newArray(m_audio_tracks->size());
        for (i = 0; i < m_audio_tracks->size(); i++) {
            rv.setProperty(i, m_engine.newQObject(m_audio_tracks->at(i), QScriptEngine::QtOwnership));
        }
 
        return static_cast<QObjectList>(*m_audio_tracks);
    }

QObjectList MediaTracks::audioTracks()
    {
        int i;

        QScriptValue rv = m_engine.newArray(m_audio_tracks->size());
        for (i = 0; i < m_audio_tracks->size(); i++) {
            rv.setProperty(i, m_engine.newQObject(m_audio_tracks->at(i), QScriptEngine::QtOwnership));
        }

        return static_cast<QObjectList>(*m_audio_tracks);
    }

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I have audioTracks[index] working but audioTracks.getTrackById("id") not.
Instead when I expose the object another way:

Q_PROPERTY(QObject* audioTracks READ audioTracks SCRIPTABLE true)
QObject* audioTracks();

Q_PROPERTY(QObject* audioTracks READ audioTracks SCRIPTABLE true)
QObject* audioTracks();

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QObject* MediaTracks::audioTracks()
    {
        m_engine.newQObject(m_audio_tracks, QScriptEngine::QtOwnership);
        return m_audio_tracks;
    }

QObject* MediaTracks::audioTracks()
    {
        m_engine.newQObject(m_audio_tracks, QScriptEngine::QtOwnership);
        return m_audio_tracks;
    }

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I have audioTracks.getTrackById("id") working but audioTracks[index] not.
Is there any way to export my object to make it possible to access it from JS both like array and like object?

[pkj]

After having introduced the qobject into script, get hold of the array QScriptValue. The idea is to introduce a native function to the the qobject.

QScriptValue arrayVal = objectScriptVal.property(QString("propertyName"));
...
 QScriptValue someFunctionName(QScriptContext *ctx, QScriptEngine *eng)
{
QObject* obj = ctx->thisObject()->toQObject();
if (obj){
 MyClass* myClassObj = qobject_cast<MyClass*>(obj);
 QObject* result = myClassObj->function(ctx->argument(0).toString());
 return result; // or return eng->newQObject(result); //both should work
}
...
arrayVal.setProperty("functionName", engine->newFunction(someFunctionName));

QScriptValue arrayVal = objectScriptVal.property(QString("propertyName"));
...
 QScriptValue someFunctionName(QScriptContext *ctx, QScriptEngine *eng)
{
QObject* obj = ctx->thisObject()->toQObject();
if (obj){
 MyClass* myClassObj = qobject_cast<MyClass*>(obj);
 QObject* result = myClassObj->function(ctx->argument(0).toString());
 return result; // or return eng->newQObject(result); //both should work
}
...
arrayVal.setProperty("functionName", engine->newFunction(someFunctionName));

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In jist: here what has been done.
1. Introduced object with an array property.
2. Got hold of QScriptValue of array property.
3. Introduce a native function to the array property.

[platon]

Still can't make it to work
pkj, did you manage to do such trick?
It seems that when my AudioTrackList is exposed to JS like array (by newArray()) then only standard JS array methods and properties are accessible.
When I try to call getTrackById() method I get such error:
http://192.168.23.2/play.html:94: TypeError: 'undefined' is not a function (evaluating 'p.audioTracks.getTrackById("id1")')

[platon]

I just found out that when I expose my object by QScriptEngine::newArray() I can't add to my object even a simple property like:

Q_PROPERTY(int myprop READ myprop SCRIPTABLE true)
int myprop() const;

Q_PROPERTY(int myprop READ myprop SCRIPTABLE true)
int myprop() const;

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In JavaScript it becomes a usual array.

[platon]

I have found a solution for my problem.
Since in JavaScript .0 and ['0'] are the same things I made the following workaround in my code:

value = m_engine.newQObject(m_audio_tracks, QScriptEngine::QtOwnership);
for (i = 0; i < m_audio_tracks->tracks().size(); i++) {
    m_audio_tracks->setProperty(QString("%1").arg(i).toLocal8Bit().data(), qVariantFromValue(m_audio_tracks->tracks().at(i)));
    value.setProperty(QString("%1").arg(i), m_engine.newQObject(m_audio_tracks->tracks().at(i), QScriptEngine::QtOwnership));
}

value = m_engine.newQObject(m_audio_tracks, QScriptEngine::QtOwnership);
for (i = 0; i < m_audio_tracks->tracks().size(); i++) {
    m_audio_tracks->setProperty(QString("%1").arg(i).toLocal8Bit().data(), qVariantFromValue(m_audio_tracks->tracks().at(i)));
    value.setProperty(QString("%1").arg(i), m_engine.newQObject(m_audio_tracks->tracks().at(i), QScriptEngine::QtOwnership));
}

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to make it possible to access my object like array from JavaScript.