Model based on QList containing objects of custom class

diredko

Hi All,
I need to expose a QList containing objects of custom class to QML as a model. The problem is that when I'm trying to do this qml 'says' that reference to model cannot be resolved. Would someone please help me out?

The custom class is defined as follows:

#include <QMetaType>

#include <QObject>

class Move
{

    Q_GADGET
    Q_PROPERTY(int fromIndex READ getFrom)
    Q_PROPERTY(int toIndex READ getTo)

private:
    int from;
    int to;

protected:
public:
    Move(int _from, int _to);
    Move():from(0), to(0){}
    Move(const Move& move):from(move.getFrom()), to(move.getTo()){}
    ~Move() {}

    int getFrom() const;
    int getTo() const;
};

Q_DECLARE_METATYPE(Move)

This is how I define a list which I'm going to expose as a model.

QList<Move>  moves;

I'm exposing the model to QML as below. With this code I receive a complaint from QML -
qrc:/qmls/Main.qml:39: ReferenceError: Moves is not defined

QQmlContext* cntx = engine.rootContext();

if(cntx != nullptr)
{
    cntx->setContextProperty("Moves", QVariant::fromValue(moves));
}

When I'm passing a number (say 64) as a model I can see that model is recognized and QML is inflated with items:

QQmlContext* cntx = engine.rootContext();

if(cntx != nullptr)
{
    cntx->setContextProperty("Moves", QVariant::fromValue(64));
}

Thanks.

mrjj

Hi
It all seems fine.
You should delete ur build folder and make sure all is recompiled.
Make sure there is a moc_ file for where Move lives.

Also test that QVariant do like your type
QVariant v = QVariant::fromValue(moves);

SGaist

Hi,

Did you register Moves ?

mrjj

he did
Q_DECLARE_METATYPE(Move)

SGaist

I was thinking about qmlRegisterType like shown in Defining QML Types from C++.

diredko

Hi,
Thanks for your suggestion. I have added the following line:

qmlRegisterType<Move>();

but it didn't help. I'm still getting same error - qrc:/qmls/Main.qml:39: ReferenceError: Moves is not defined

SGaist

How are you using that type in your QML code ?

diredko

@SGaist
I'm not using Move type in QML directly. I'm only accessing model which is a QList<Move> as below:

Column
{
      Repeater
      {
          model: Moves

          Text {height: 20; width: 20; text: "HELLO"}
      }
}

Also I tried a little "experiment" as @mrjj suggested:

Move move(1, 2);

QVariant var = QVariant::fromValue(move);

Move move1 = var.value<Move>();

std::cout << move1.getFrom() << " " << move1.getTo() << std::endl;

This code outputs "1 2" as expected

SGaist

Ok, then there are some small things to do in order to use that class directly from QML. See here.

ultramanjones

@diredko What is the answer? This thread is incomplete, 4 years old or not.