Qt Reference Documentation

# downloader.cpp Example File

webkit/webftpclient/downloader.cpp

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     #include <QFileDialog>
     #include <QMessageBox>
     #include <QNetworkRequest>
     #include <QNetworkReply>
     #include "downloader.h"

     Downloader::Downloader(QWidget *parentWidget, QNetworkAccessManager *manager)
         : QObject(parentWidget), manager(manager), parentWidget(parentWidget)
     {
     }

     QString Downloader::chooseSaveFile(const QUrl &url)
     {
         QString fileName = url.path().split("/").last();
         if (!path.isEmpty())
             fileName = QDir(path).filePath(fileName);

         return QFileDialog::getSaveFileName(parentWidget, tr("Save File"), fileName);
     }

     void Downloader::startDownload(const QNetworkRequest &request)
     {
         downloads[request.url().toString()] = chooseSaveFile(request.url());

         QNetworkReply *reply = manager->get(request);
         connect(reply, SIGNAL(finished()), this, SLOT(finishDownload()));
     }

     void Downloader::saveFile(QNetworkReply *reply)
     {
         QString newPath = downloads[reply->url().toString()];

         if (newPath.isEmpty())
             newPath = chooseSaveFile(reply->url());

         if (!newPath.isEmpty()) {
             QFile file(newPath);
             if (file.open(QIODevice::WriteOnly)) {
                 file.write(reply->readAll());
                 file.close();
                 path = QDir(newPath).dirName();
                 QMessageBox::information(parentWidget, tr("Download Completed"),
                                          tr("Saved '%1'.").arg(newPath));
             } else
                 QMessageBox::warning(parentWidget, tr("Download Failed"),
                                      tr("Failed to save the file."));
         }
     }

     void Downloader::finishDownload()
     {
         QNetworkReply *reply = static_cast<QNetworkReply *>(sender());
         saveFile(reply);
         downloads.remove(reply->url().toString());
         reply->deleteLater();
     }