Question

I have a qt quick project where I am trying to emit a signal from QML and connect to a slot in C++.

QML file

import QtQuick 1.0
//import com.net 1.0

Column {
id: mainCol
x: 20; y: 80
width: 320
//height: 62
opacity: 0

//NetCom{ id: netcom}


Rectangle{
    signal tcpMsg(string address, int port)
    objectName: "topRec"
    id: topRec
    width: 40; height: 40
    color: "blue"
    Text{
        text: "send tcp msg"; font.pointSize: 14
        anchors.verticalCenter: topRec.verticalCenter
        anchors.left: topRec.right
        anchors.rightMargin: 10
    }
    Text{
        id: statusTxt
        //text: cppInterface.qml_text ; font.pointSize: 12
        text: "status: "; font.pointSize: 12
        anchors.horizontalCenter: topRec.horizontalCenter
        anchors.top: topRec.bottom
        anchors.bottomMargin: 10
    }

    MouseArea {
        id: mouseArea
        transformOrigin: Item.Center
        anchors.fill: parent //anchor all sides of the mouse area to the rectangle's anchors
        onClicked: {
            topRec.tcpMsg("127.0.0.1", 8888)
            console.log("clicked")
        }
    }
}


states:[
   State {
        name: "visible";
        PropertyChanges { target:mainCol; opacity: 1;}
    }
]

transitions:[
  Transition {
        from:""; to: "visible"; reversible: true
        NumberAnimation { properties: "opacity"; duration: 500; easing.type: Easing.InOutQuad }
    }
]

}

C++ file

#include <QtGui/QApplication>
#include <QtDeclarative>

#include "qmlcppmediator.h"
#include "qmlapplicationviewer.h"
#include "kernelcom.h"
#include "netcom.h"


Q_DECL_EXPORT int main(int argc, char *argv[])
{
QScopedPointer<QApplication> app(createApplication(argc, argv));
//needed to use C++ code in QML
qmlRegisterType<KernelCom>("com.kernel", 1, 0, "KernelCom");
qmlRegisterType<NetCom>("com.net", 1, 0, "NetCom");


QmlApplicationViewer viewer;
viewer.setWindowFlags(Qt::FramelessWindowHint);
viewer.setOrientation(QmlApplicationViewer::ScreenOrientationAuto);
viewer.setMainQmlFile(QLatin1String("qml/testMenu/main.qml"));

//make signal from Qml file trigger slots in C++
QDeclarativeView view;
view.setSource(QUrl::fromLocalFile("qml/testMenu/TCPmenu.qml"));
QObject *object = view.rootObject();
QObject *child = object->findChild<QObject*>("topRec");

qDebug()<<child;
NetCom client;

qDebug()<<QObject::connect(child,SIGNAL(tcpMsg(QString, quint16)), &client, SLOT(start(QString, quint16)));


viewer.showExpanded();

return app->exec();
}

I keep getting the following error message

 QDeclarativeRectangle_QML_3(0x99c5998, name = "topRec") 
 Object::connect: No such signal QDeclarativeRectangle_QML_3::tcpMsg         (QString, quint16)
 Object::connect:  (sender name:   'topRec')
 false 

I have tried using QDecarativeEngine, putting the signal in the main qml item so I dont have use get child and I keep getting the message above.

Thanks

Answer 1

Just figured it out, it wouldnt connect because I was using qunit16 datatype instead of using int in
I changed the line to this

    connect(child,SIGNAL(tcpMsg(QString, int)), &client, SLOT(start(QString, int))) 

and then it connected.

Also I didnt need QDeclarativeView I eneded up setting the rootObject from QmlApplicationViewer viewer;