How to emit signal with variable as reference from qml to c++

econtech

I want to emit signal with list of objects as a reference fro QML to c++ code. In c++ i am accessing the reference.

I worked for long time but i am not able to get it.

Is there any idea to achieve. Please give suggestion.

Thanks in advance

melghawi

Hi there.

I came up with a quick example that does what you want but with strings instead. Should follow the same concept for objects.

main.qml
@import QtQuick 2.0

Item {
width: 800
height: 600
signal listSignal(var list)

property variant stringList: ["one", "two", "three"]

Timer {
    interval: 2000
    onTriggered: listSignal(stringList)
    running: true
}

}

@

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

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

QtQuick2ApplicationViewer viewer;
viewer.setMainQmlFile&#40;QStringLiteral("qml/Testing/main.qml"&#41;);
viewer.showExpanded();

SignalCatcher signalCatcher(viewer.rootObject());

return app.exec();

}
@

signalcatcher.h
@#ifndef SIGNALCATCHER_H
#define SIGNALCATCHER_H

#include <QObject>
#include <QVariant>

class QQuickItem;

class SignalCatcher : public QObject
{
Q_OBJECT

public:
SignalCatcher(QQuickItem *rootItem, QObject *parent = NULL);

private slots:
void processList(const QVariant &var);
};

#endif // SIGNALCATCHER_H
@

signalcatcher.cpp
@#include <QQuickItem>
#include "signalcatcher.h"

SignalCatcher::SignalCatcher(QQuickItem *rootItem, QObject *parent)
: QObject(parent)
{
connect(rootItem, SIGNAL(listSignal(QVariant)), this, SLOT(processList(QVariant)));
}

void SignalCatcher::processList(const QVariant &var)
{
QStringList list = var.toStringList();
for(int i = 0; i < list.size(); i++)
{
qDebug(list[i].toStdString().c_str());
}
}
@