How to use Qhttp for downloading?? with the following code..

[Gokulnathvc]

void MyClass::doSth()
> > {
> > QHttp http( "www.google.com" );
> > connect(&http, SIGNAL(done(bool)), this, SLOT(httpdone(bool)));
> > QFile file( "temp.txt" );
> > file.open( QIODevice::WriteOnly );
> > mutex.lock();
> > http.get( "/" );
> > fin.wait( &mutex );
> > file.close();
> > mutex.unlock();
> > }
> >
> > (protected slots
> >
> > void MyClass::httpdone(bool error)
> > {
> > if (error == false)
> > {
> > fin.wakeAll();
> > }

The file is not getting downloaded.. please help me

[squidge]

Don't use QHttp, the class is obsolete. Use QNetworkAccessManager. See the examples that come with Qt, and your previous topics on this very same subject.

[Gokulnathvc]

One problem in using the QNetworkAccessManager, that is the final loop finished loop is called only at the final execution of the program. So that the download cannot be achieved in the program only after the complete execution. The functions going to use the downloaded file fails.Please give me a solution.

[squidge]

So your application attempts to do network access when your program terminates? So you need to do this before you exit your main event loop. You can't expect signals and slots to work without a functioning event loop.

[Gokulnathvc]

Yes thats correct, How to make this done before my main event??

[squidge]

Before? You were saying above that it was "at the final execution of the program".

Which is it?

[Gokulnathvc]

Yes. readReady() and finished() functions under startRequest() using QNetworkAccessManager??.... In which readReady() and finished() functions are called only at the final execution of the program..

[Gokulnathvc]

Simplest way to download from the HTTP is below::

connect(&http,SIGNAL(done(bool)),this,SLOT(httpdone()));  //added in the constructor..

connect(&http,SIGNAL(done(bool)),this,SLOT(httpdone()));  //added in the constructor..

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In the header file......Make the following changes...

QHttp http;
    QFile file;
 
private slots:
    bool on_pushButton_clicked();
    void httpdone();
 
signals:
    void done();
 
in the Qthttp.cpp file...
 
bool QtHttp::on_pushButton_clicked()
{
 
    QString strUrl="http://www.blabla.com//file";
       QUrl url = QUrl::fromUserInput(strUrl);
 
        QFileInfo fileInfo(url.path());
        QString strhost=url.encodedHost();
        QString filename=fileInfo.fileName();
        file.setFileName("C:\\Qt\\QHttp\\"+filename);
       http.setHost(url.host(),url.port(80));
       http.get(url.path(),&file);
 
       if(!file.open(QIODevice::WriteOnly))
       {
           QMessageBox::warning(NULL,"warning","file is not opened",QMessageBox::Ok);
       }
       file.write(http.readAll());
       http.close();
       return true;
 
}
 
void QtHttp::httpdone()
{
 
    file.close();
    Q_EMIT done();
}

QHttp http;
    QFile file;

private slots:
    bool on_pushButton_clicked();
    void httpdone();

signals:
    void done();

in the Qthttp.cpp file...

bool QtHttp::on_pushButton_clicked()
{

    QString strUrl="http://www.blabla.com//file";
       QUrl url = QUrl::fromUserInput(strUrl);

        QFileInfo fileInfo(url.path());
        QString strhost=url.encodedHost();
        QString filename=fileInfo.fileName();
        file.setFileName("C:\\Qt\\QHttp\\"+filename);
       http.setHost(url.host(),url.port(80));
       http.get(url.path(),&file);

       if(!file.open(QIODevice::WriteOnly))
       {
           QMessageBox::warning(NULL,"warning","file is not opened",QMessageBox::Ok);
       }
       file.write(http.readAll());
       http.close();
       return true;

}

void QtHttp::httpdone()
{

    file.close();
    Q_EMIT done();
}

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[ChrisW67]

What are you trying to achieve? Is it some sort of "download a set of data before the main window shows" problem?

#include <QtGui>
#include <QtNetwork>
#include <QDebug>
 
class MainWindow: public QMainWindow {
    Q_OBJECT
public:
    MainWindow(QWidget *p = 0): QMainWindow(p) {
        QWidget *central = new QWidget(this);
        QPushButton *button1 = new QPushButton("Button", this);
        QLabel *label1 = new QLabel("Label", this);
 
        QVBoxLayout *layout = new QVBoxLayout(central);
        layout->addWidget(button1);
        layout->addWidget(label1);
 
        central->setLayout(layout);
        setCentralWidget(central);
    }
public slots:
 
private:
};
 
class Downloader: public QObject {
    Q_OBJECT
public:
    Downloader(QObject *p = 0): QObject(p) {
        manager = new QNetworkAccessManager(this);
        connect(manager, SIGNAL(finished(QNetworkReply*)),
          this, SLOT(replyFinished(QNetworkReply*)));
 
    }
 
    void start() { 
        manager->get(QNetworkRequest(QUrl("http://qt.nokia.com")));
    }
private slots:
    void replyFinished(QNetworkReply *reply) {
        // Save the received data
        qDebug() << "Saving the received data";
        //
        emit done();
    }
signals:
    void done();
private:
    QNetworkAccessManager *manager;
};
 
 
int main(int argc, char *argv[])
{
    QApplication app(argc, argv);
 
 
    MainWindow m;   // create but do not show()
    Downloader d;
    QObject::connect(&d, SIGNAL(done()), &m, SLOT(show()));
    d.start();
 
    return app.exec();
}
#include "main.moc"

#include <QtGui>
#include <QtNetwork>
#include <QDebug>

class MainWindow: public QMainWindow {
    Q_OBJECT
public:
    MainWindow(QWidget *p = 0): QMainWindow(p) {
        QWidget *central = new QWidget(this);
        QPushButton *button1 = new QPushButton("Button", this);
        QLabel *label1 = new QLabel("Label", this);

        QVBoxLayout *layout = new QVBoxLayout(central);
        layout->addWidget(button1);
        layout->addWidget(label1);

        central->setLayout(layout);
        setCentralWidget(central);
    }
public slots:

private:
};

class Downloader: public QObject {
    Q_OBJECT
public:
    Downloader(QObject *p = 0): QObject(p) {
        manager = new QNetworkAccessManager(this);
        connect(manager, SIGNAL(finished(QNetworkReply*)),
          this, SLOT(replyFinished(QNetworkReply*)));

    }

    void start() { 
        manager->get(QNetworkRequest(QUrl("http://qt.nokia.com")));
    }
private slots:
    void replyFinished(QNetworkReply *reply) {
        // Save the received data
        qDebug() << "Saving the received data";
        //
        emit done();
    }
signals:
    void done();
private:
    QNetworkAccessManager *manager;
};


int main(int argc, char *argv[])
{
    QApplication app(argc, argv);


    MainWindow m;   // create but do not show()
    Downloader d;
    QObject::connect(&d, SIGNAL(done()), &m, SLOT(show()));
    d.start();

    return app.exec();
}
#include "main.moc"

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