ListElement: cannot use script for property value error [Qt Quick/C++]

[kingsta]

Hi guys

I want to use Qt Quick/C++ together. For this, I wrote SteelProfile Class (C++) and own functions. I can't assign "steelprofileID.steelStandardName" value to ListElement. There is a weird situation. This code(on below) shows to me correct value, but I can't assign to ListElement. I got ListElement: cannot use script for property value error.

@console.log("Value: " + steelprofileID.steelStandardName)@

There is the problem?

steelprofile.h
@class SteelProfile : public QObject
{
Q_OBJECT
Q_PROPERTY(QString steelStandardName READ steelStandardName WRITE setSteelStandardName) //NOTIFY steelStandardNameChanged
public:
explicit SteelProfile(QObject *parent = 0);

signals:

public slots:
Q_INVOKABLE QString steelStandardName() const;
void setSteelStandardName(const QString &steelStandardName);

private:
QString sName;

};@

steelprofile.cpp
@SteelProfile::SteelProfile(QObject *parent) :
QObject(parent)
{
qDebug() << "SteelProfile()";

sName = "Europe";

}

QString SteelProfile::steelStandardName() const{

qDebug() << "steelStandardName()";

return sName;

}

void SteelProfile::setSteelStandardName(const QString &steelStandardName){

qDebug() << "setSteelStandardName()";

sName = steelStandardName;

}
@

qml file
@import QtQuick 2.1
import QtQuick.Controls 1.1
import QtQuick.Controls.Styles 1.1

import SteelProfile 1.0

Item {
width: parent.width
height: parent.height

SteelProfile{
    id: steelprofileID
    steelStandardName: "Europe"
}

ListModel{
    id:steelStandardModel

    ListElement{
        //steelStandardName: "Europe"
        steelStandardName: steelprofileID.steelStandardName //Gets error here
        ...
    }

    ListElement{
        steelStandardName: "US"
        ...
    }
}

...
@

main.cpp
@#include <QtGui/QGuiApplication>
#include "qtquick2applicationviewer.h"
#include "steelprofile.h"

#include <QQmlApplicationEngine>
#include <QQuickWindow>
#include <QQmlComponent>

int main(int argc, char *argv[])
{
QGuiApplication app(argc, argv);

qmlRegisterType<SteelProfile>("SteelProfile", 1,0, "SteelProfile");

SteelProfile *sProfile = new SteelProfile;

QQmlApplicationEngine engine;
engine.load(QUrl("qml/StackView1/main.qml"));

QObject *topLevel = engine.rootObjects().value(0);
QQuickWindow *window = qobject_cast<QQuickWindow *>(topLevel);
window->show();
return app.exec();

}
@

[onek24]

Hello, try to put your
@Q_INVOKABLE QString steelStandardName() const;@
as
@QString steelStandardName() const;@
in public and not in public slot. Probably this will fix it, but im not absolutely sure. For further information please read:
"Defining New QML Elements":http://qt-project.org/doc/qt-4.8/qtbinding.html#defining-new-qml-elements

[kingsta]

[quote author="onek24" date="1391100071"]Hello, try to put your
@Q_INVOKABLE QString steelStandardName() const;@
as
@QString steelStandardName() const;@
in public and not in public slot. Probably this will fix it, but im not absolutely sure. For further information please read:
"Defining New QML Elements":http://qt-project.org/doc/qt-4.8/qtbinding.html#defining-new-qml-elements
[/quote]

Firstly, thanks for relpy.

I changed my header file and I got the error again

header file
@...
public:
explicit SteelProfile(QObject *parent = 0);

QString steelStandardName() const;
void setSteelStandardName(const QString &steelStandardName);

...@

[onek24]

Alright, i'll check it out tomorrow.

[SGaist]

Hi,

You should take a look at the example in:
qt5_intall_folder/qtquick1/examples/declarative/modelviews/objectlistmodel/ you have an example of an object implemented in C++ that you can then use in QML

Hope it helps

[kingsta]

[quote author="SGaist" date="1391113099"]Hi,

You should take a look at the example in:
qt5_intall_folder/qtquick1/examples/declarative/modelviews/objectlistmodel/ you have an example of an object implemented in C++ that you can then use in QML

Hope it helps[/quote]

Firstly, Im sorry for the late my answer. I've been away.

In this example, @Text { text: name }@ code perfectly runs. I can't understand @color: model.modelData.color@ code. What is the model and modelData? Where did they declare?

I use the same figure as that example. But I can't fix the issue.
@steelStandardName: steelprofileID.steelStandardName@
or
@steelStandardName: SteelProfile.steelStandardName@
This two codes didn't run.

I write some explanations to easly understand code.
steelStandardName: ListElement object
steelprofileID: SteelProfile object in qml
steelStandardName: A function in cpp file and returns QString name of steel standard.

What should I do my friends?

[Rolias]

Well even though this is ten months old I'll post an answer to this latest question for any future visitors. model is a property on the ListView that lets you walk up the chain to the model from the delegate. The modelData property holds the QObject*. This makes the properties of the object directly accessible in the ListView delegate using the syntax shown that is:
@model.modelData.color@

is returning the Q_PROPERTY color property from the DataObject instance.