重构为独立类后，QNetworkRequest (HTTP GET) 不会触发

Question

我最近开始了对大约两个月前编写的大型整体音频播放器应用程序进行模块化的繁琐过程。

这个过程进展得相当顺利，尽管其中一种方法（ScrobbleMedia - 可以预见的是，该方法足以使 HTTP 请求向 last.fm 提交有关播放曲目的信息）似乎不再发出网络请求。

但是，将正确构建将传递到 QNetworkAccessManager 实例/QNetworkRequest 的 QUrl 对象。

为了进行比较，BitBucket 上提供了代码的功能性 Mercurial 版本。

重构后，ScrobbleMedia 方法当前如下所示：

#include "scrobblemedia.h"

#include <QDebug>
#include <cstdio>

ScrobbleMedia::ScrobbleMedia(QString asUsername, QString asPassword,
                         QString asArtist, QString asTrack, QString asAlbum)
{

    QString KEndPointURL = "http://lastfmstats.livefrombmore.com/universalscrobbler/scrobble.php";
    QUrl iScrobbleEndPoint(KEndPointURL);

      QNetworkAccessManager *iScrobbleDispatcher = new QNetworkAccessManager(this);


iScrobbleEndPoint.addQueryItem("submissionType","track");
iScrobbleEndPoint.addQueryItem("username", asUsername);
iScrobbleEndPoint.addQueryItem("password", asPassword);
iScrobbleEndPoint.addQueryItem("artist", asArtist);
iScrobbleEndPoint.addQueryItem("track", asTrack);
iScrobbleEndPoint.addQueryItem("album", asAlbum);
iScrobbleEndPoint.addQueryItem("number","1");
iScrobbleEndPoint.addQueryItem("duration","200");

iScrobbleDispatcher->get(QNetworkRequest(iScrobbleEndPoint));
connect(iScrobbleDispatcher, SIGNAL(finished(QNetworkReply*)),
 SLOT(replyFinished(QNetworkReply*)));

// QString Outside = iScrobbleEndPoint.toEncoded();

qDebug()  << "Received: " + 
  asUsername + " " + 
   asPassword + " " + 
    asArtist + " " +
     asTrack + " " + 
      asAlbum;

qDebug() << iScrobbleEndPoint.toString();

}

ScrobbleMedia::~ScrobbleMedia() {

}

关联的头文件如下所示：

#ifndef SCROBBLEMEDIA_H
#define SCROBBLEMEDIA_H

#include <QString>
#include <QtNetwork>
#include <QUrl>
#include <QNetworkAccessManager>



class ScrobbleMedia : public QObject
{
     Q_OBJECT;


private:

public:

    ScrobbleMedia(QString asUsername, QString asPassword, QString asArtist, QString asTrack, QString asAlbum);
    ~ScrobbleMedia();

};

#endif // SCROBBLEMEDIA_H

我目前正在 Windows 下针对 Qt 库版本 4.7.0 的 MinGW 版本（包含在 Qt SDK 2010.05 中）构建应用程序本身7x86-64。

任何帮助将不胜感激。

提前致谢。

Answer 1

在阅读了许多不同的信息来源（其中大多数是矛盾的）之后，我发现以下结果产生了一个可行的解决方案 - 尽管调试输出中存在一个外观问题，但似乎并不影响操作（Object::connect：没有这样的信号 QNetworkReplyImpl::finished(QNetworkReply*) in ../AudioPlayer/scrobblemedia.cpp:29)：

在 scrobblemedia.cpp 中：

#include "scrobblemedia.h"

#include <QDebug>
#include <cstdio>

ScrobbleMedia::ScrobbleMedia(QString asUsername, QString asPassword,
                             QString asArtist, QString asTrack, QString asAlbum)
{

    QByteArray iDataSink;
    QEventLoop iLoop;

    QString KEndPointURL = "http://lastfmstats.livefrombmore.com/universalscrobbler/scrobble.php";
    QUrl iScrobbleEndPoint(KEndPointURL);

    iScrobbleEndPoint.addQueryItem("submissionType","track");
    iScrobbleEndPoint.addQueryItem("username", asUsername);
    iScrobbleEndPoint.addQueryItem("password", asPassword);
    iScrobbleEndPoint.addQueryItem("artist", asArtist);
    iScrobbleEndPoint.addQueryItem("track", asTrack);
    iScrobbleEndPoint.addQueryItem("album", asAlbum);
    iScrobbleEndPoint.addQueryItem("number","1");
    iScrobbleEndPoint.addQueryItem("duration","200");

    QNetworkAccessManager iScrobbleDispatcher;
    QNetworkRequest iScrobbleRequest(iScrobbleEndPoint);
    QNetworkReply *iScrobbleReply = iScrobbleDispatcher.get(iScrobbleRequest);

    QObject::connect(iScrobbleReply, SIGNAL(finished(QNetworkReply*)), &iLoop,
     SLOT(quit()));

    iDataSink = iScrobbleReply->readAll();

    qDebug()  << "Received: " + asUsername + " " + asPassword + " " + asArtist + " " + asTrack + " " + asAlbum;

    qDebug() << iScrobbleEndPoint.toString();

    iLoop.exec();
}

ScrobbleMedia::~ScrobbleMedia() {

}

void ScrobbleMedia::replyFinished(QNetworkReply*) {

}

void ScrobbleMedia::reallyDone() {

    qDebug() << "We've probably successfully Scrobbled...";
}

在 中scrobblemedia.h：

#ifndef SCROBBLEMEDIA_H
#define SCROBBLEMEDIA_H

#include <QString>
#include <QtNetwork>
#include <QUrl>
#include <QNetworkAccessManager>



class ScrobbleMedia : public QObject
{
     Q_OBJECT


private:


public:

    ScrobbleMedia(QString asUsername, QString asPassword, QString asArtist, QString asTrack, QString asAlbum);
    ~ScrobbleMedia();

private slots:
    void replyFinished(QNetworkReply*);
    void reallyDone();

};

#endif // SCROBBLEMEDIA_H

感谢大家的帮助。

希望这段代码将来能够作为其他人的有用模板。