QWidget中嵌入QQuickWidget，从qml端鼠标获取经纬度点(double类型)，发到c++端。把c++端的对象暴露个qml端调用

qml端鼠标选取点

c++端接收

c++端
先写一个类，专门用来接收，取名MouseDrawAirspace

#ifndef MOUSEDRAWAIRSPACE_H
#define MOUSEDRAWAIRSPACE_H


#include <QVariant>
#include <QObject>
#include <QGeoCoordinate>
#include <QDebug>
#include <QList>

class MouseDrawAirspace : public QObject
{
    Q_OBJECT

public:
    explicit MouseDrawAirspace(QObject *parent=nullptr);
    ~MouseDrawAirspace();

public slots:
    // 槽函数，用于接收多边形点坐标
    void receivePoints( QVariantList points) ;

    void receiveCoordinates(QVector<QPointF> coordinates1);

 public:
    QList<QPointF>store_multiPolyon;

};

#endif // MOUSEDRAWAIRSPACE_H

cpp

#include "mousedrawairspace.h"

MouseDrawAirspace::MouseDrawAirspace(QObject *parent):QObject(parent)

{
//我要使用这种类型，作为对外通信，所以先注册吧，之后要用
    qRegisterMetaType <QList<QPointF>>(" QList<QPointF>");
}
MouseDrawAirspace::~MouseDrawAirspace()
{
}

void MouseDrawAirspace::receivePoints( QVariantList points)
{
    for (const auto& pointVariant : points) {
        // 将 QVariant 转换为 QVariantList，代表单个坐标点
        QVariantList pointList = pointVariant.toList();
        if (pointList.size() == 2)
        {
            // 获取 x 和 y 坐标

            double x = pointList[0].toDouble();
            double y = pointList[1].toDouble();
             QPointF p;
             p.setX(x);
             p.setY(y);
            store_multiPolyon.append(p);
            qDebug() << "Received point: (" << x << ", " << y << ")";
        }

    }

}
void MouseDrawAirspace::receiveCoordinates(QVector<QPointF> coordinates1)
{

    for (const auto &point : coordinates1) {
        qDebug() << "Coordinate:" << point;
    }
}

通过上下文，把接口暴露个qml端。
意思：qml端可以调用这个类对象

  //手动拾取空域点
    mouseDrawAirSpace=new MouseDrawAirspace();
  //  MouseDrawAirspace temdddd;
    ui->quickWidget->rootContext()->setContextProperty("MouseDrawAirspace",mouseDrawAirSpace);

来看qml端
核心代码

 MouseArea{
 //用来存放鼠标选取的经纬度点
   property var points: []
   onClicked: {
	 var coord = the_map.toCoordinate(Qt.point(mouseX,mouseY),false);
          templist.push(coord);

	}
	//双击后，把里面保存到经纬度点发到c++端
 onDoubleClicked: {
  // 遍历 templist 提取经纬度并添加到 points 中
            for (var i = 0; i < templist.length; i++)
            {
                var currentCoordinate = templist[i];
                var longti = currentCoordinate.longitude;
                var lati = currentCoordinate.latitude;
                var point1 = [longti, lati];
                points.push(point1);
            }
     //MouseDrawAirspace就是通过上下文注册的那个对象
 	 MouseDrawAirspace.receivePoints(points)
}

}

全部模块代码

 /****************双击生成多边形******************/
  MouseArea{
    id:mouse_polygon
    property var list: [[]]
    property var templist: []
    property var points: []

    anchors.fill: parent
    hoverEnabled: true;
    enabled:polygon_flag != 0
    onClicked: {
      if(polygon_flag == 1 && mouse.button == Qt.LeftButton)
      {

        if(!ruler)
        {
          ruler = ruler_comp.createObject(the_map);
          if(ruler)
          {
            the_map.addMapItemGroup(ruler)
          }
        }
        if(ruler){
          console.log("111 " + i);
          var coord = the_map.toCoordinate(Qt.point(mouseX,mouseY),false);
          templist.push(coord);
          console.log(item_rect_point_List)
          ruler.appendPoint(coord);
        }
      }
    }
    onPositionChanged: {
      if(polygon_flag === 1)
      {
        if(ruler)
        {
          var coord = the_map.toCoordinate(Qt.point(mouseX,mouseY),false);

          ruler.followMouse(coord);
            update()
        }
      }
    }
    onDoubleClicked: {
      if(polygon_flag === 1){
        if(ruler)
        {
          ruler.closePath();
          ruler.destoryLine();
          ruler = null;
        }
        var component = Qt.createComponent("MyPolygon.qml");
        console.log(component.errorString());
        if(component.status === Component.Ready)
        {

          var polygon = component.createObject(the_map)
          polygon._list = templist

            // 遍历 templist 提取经纬度并添加到 points 中
            for (var i = 0; i < templist.length; i++)
            {
                var currentCoordinate = templist[i];
                var longti = currentCoordinate.longitude;
                var lati = currentCoordinate.latitude;
                var point1 = [longti, lati];
                points.push(point1);
            }
   // 发送坐标点到 C++ 端  
             MouseDrawAirspace.receivePoints(points)

//测试，通不通
//            var coordinates = []
//            for (var i = 0; i < 30; ++i) {
//                // 这里简单生成一些示例坐标点，你可以根据实际需求修改
//                coordinates.push(Qt.point(i * 10.2, i * 20))
//            }
// 			MouseDrawAirspace.receiveCoordinates(points)
         
           
          the_map.addMapItemGroup(polygon)
        }
        templist.splice(0,templist.length)
        polygon_flag = 0;
        update()
      }
    }

  }