使用QQuickWidget窗口时、绑定的信号想传string出来怎么办

请问下使用QQuickWidget窗口时、绑定的信号想传string出来怎么办
import QtQuick 2.9
import QtQuick.Controls 2.2
import QtQuick.Layouts 1.3

Item {  
    id: item
    anchors.fill: parent
    signal sendControlCmdToCamera(string cmd) 
    signal test(string str) 
    Rectangle 
    {  
        //行布局
        Grid 
        {
            columns: 2
            spacing: 6
            Button{
                text: '聚焦+'
                onClicked: 
                {
                    //sendControlCmdToCamera("http://192.168.1.88/cgi-bin/hi3510/param.cgi?cmd=ptzctrl&-step=0&-act=zoomin&-speed=45&-usr=admin&-pwd=1234qwer")
                    test("clicked");
                    console.log("clicked")
                }
            }
            Button{
                text: '聚焦-'
                onClicked: model.submit()
            }
            Button{
                text: '拉进'
                onClicked: model.submit()
            }
            Button{
                text: '拉远'
                onClicked: model.submit()
            }
        }
    }  
}  

信号链接:

QQuickItem *item = ui.quickWidget->rootObject();
//    QObject * obj = (QObject*)item;
    connect(item, SIGNAL(test(string)), this, SLOT(aaa(string)));

如果信号和槽函数都使用string槽函数不会响应。

你传出qstring,然后将qstring再转为string就可以了

connect(item, SIGNAL(test(string)), this, SLOT(aaa(string)));这里要用QString