QObject:connect没有这样的插槽问题

Question

我不知道为什么会发生这种情况.我已经扩展QObject并添加了宏Q_OBJECT.信号和插槽也有相同的参数.

我已经发布了原始问题

http://supportforums.blackberry.com/t5/Cascades-Development/Object-connect-No-such-slot-problem/mp/2486753

这是我的hpp文件:

/*
 * LocationMonitor.hpp
 *
 *  Created on: Jul 13, 2013
 *      Author: Roland
 */

#ifndef LOCATIONMONITOR_HPP_
#define LOCATIONMONITOR_HPP_

#include <QObject>
#include <QtLocationSubset/qgeopositioninfo.h>
#include <QtLocationSubset/qgeoareamonitor.h>

using namespace Qt;
using namespace QtMobilitySubset;
class GeoNotification;
class LocationMonitor : public QObject
{
    Q_OBJECT
public:
    LocationMonitor(int id,GeoNotification *geoNotification,QVariantList locationList,QVariantList actionList);
    virtual ~LocationMonitor();

public slots:
    void areaEnteredd(QtMobilitySubset::QGeoPositionInfo info);
    void areaExitedd(QtMobilitySubset::QGeoPositionInfo info);

public:
    QGeoAreaMonitor *monitor;
};

#endif /* LOCATIONMONITOR_HPP_ */

这是我的cpp文件

/*
 * LocationMonitor.cpp
 *
 *  Created on: Jul 13, 2013
 *      Author: Roland
 */

#include "LocationMonitor.hpp"

LocationMonitor::LocationMonitor(int id,GeoNotification *geoNotification,QVariantList locationList,QVariantList actionList):
geoNotification(geoNotification)
{
    monitor = QGeoAreaMonitor::createDefaultMonitor(this);
    QObject::connect(monitor, SIGNAL(areaEntered(QGeoPositionInfo)),this, SLOT(areaEnteredd(QGeoPositionInfo)));
    QObject::connect(monitor, SIGNAL(areaExited(QGeoPositionInfo)),this, SLOT(areaExitedd(QGeoPositionInfo)));
}
LocationMonitor::~LocationMonitor() {}

void LocationMonitor::areaEnteredd(QGeoPositionInfo info)
{
}
void LocationMonitor::areaExitedd(QGeoPositionInfo info)
{
}

API文档链接在这里

谢谢.

Answer 1

您需要在任何地方使用相同的名称:在信号声明,插槽声明和连接中.那是因为该connect()机制基于文本比较.

由于原始信号仅const QGeoPositionInfo &作为参数声明,因此您需要设置此信号,并且仅设置此信号.

以下是您应该使用的声明:

    // Header
    public slots:
        void areaEnteredd(const QGeoPositionInfo& info);
        void areaExitedd(const QGeoPositionInfo& info);

    // CPP
    void LocationMonitor::areaEnteredd(const QGeoPositionInfo& info)
    {
    }
    void LocationMonitor::areaExitedd(const QGeoPositionInfo& info)
    {
    }
    // Connects
    QObject::connect(monitor, SIGNAL(areaEntered(const QGeoPositionInfo&)),this, SLOT(areaEnteredd(const QGeoPositionInfo&)));
    QObject::connect(monitor, SIGNAL(areaExited(const QGeoPositionInfo&)),this, SLOT(areaExitedd(const QGeoPositionInfo&)));

请注意,您必须QtMobilitySubset在标头中使用命名空间,这很糟糕.您可以将范围限制为您真正需要的范围:using ::QtMobilitySubset::QGeoPositionInfo;而不是完整范围using namespace QtMobilitySubset;.