в 14:21, 25 мая 2010

2010-05-25T14:21:06Z

Admin: 1 версия: Импорт контента...

2010-05-25T10:24:33Z

1 версия: Импорт контента...

Новая страница

==Download from URL==

<source lang="cpp">
/****************************************************************************
**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the examples of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial Usage
** Licensees holding valid Qt Commercial licenses may use this file in
** accordance with the Qt Commercial License Agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Nokia.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file. Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain additional
** rights. These rights are described in the Nokia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file. Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
** met: http://www.gnu.org/copyleft/gpl.html.
**
** If you have questions regarding the use of this file, please contact
** Nokia at qt-info@nokia.com.
** $QT_END_LICENSE$
**
****************************************************************************/
#include <QCoreApplication>
#include <QFile>
#include <QFileInfo>
#include <QList>
#include <QNetworkAccessManager>
#include <QNetworkRequest>
#include <QNetworkReply>
#include <QStringList>
#include <QTimer>
#include <QUrl>
#include <stdio.h>
class DownloadManager: public QObject
{
Q_OBJECT
QNetworkAccessManager manager;
QList<QNetworkReply *> currentDownloads;
public:
DownloadManager();
void doDownload(const QUrl &url);
QString saveFileName(const QUrl &url);
bool saveToDisk(const QString &filename, QIODevice *data);
public slots:
void execute();
void downloadFinished(QNetworkReply *reply);
};
DownloadManager::DownloadManager()
{
connect(&manager, SIGNAL(finished(QNetworkReply*)),
SLOT(downloadFinished(QNetworkReply*)));
}
void DownloadManager::doDownload(const QUrl &url)
{
QNetworkRequest request(url);
QNetworkReply *reply = manager.get(request);
currentDownloads.append(reply);
}
QString DownloadManager::saveFileName(const QUrl &url)
{
QString path = url.path();
QString basename = QFileInfo(path).fileName();
if (basename.isEmpty())
basename = "download";
if (QFile::exists(basename)) {
// already exists, don"t overwrite
int i = 0;
basename += ".";
while (QFile::exists(basename + QString::number(i)))
++i;
basename += QString::number(i);
}
return basename;
}
bool DownloadManager::saveToDisk(const QString &filename, QIODevice *data)
{
QFile file(filename);
if (!file.open(QIODevice::WriteOnly)) {
fprintf(stderr, "Could not open %s for writing: %s\n",
qPrintable(filename),
qPrintable(file.errorString()));
return false;
}
file.write(data->readAll());
file.close();
return true;
}
void DownloadManager::execute()
{
QStringList args = QCoreApplication::instance()->arguments();
args.takeFirst(); // skip the first argument, which is the program"s name
if (args.isEmpty()) {
printf("Qt Download example - downloads all URLs in parallel\n"
"Usage: download url1 [url2... urlN]\n"
"\n"
"Downloads the URLs passed in the command-line to the local directory\n"
"If the target file already exists, a .0, .1, .2, etc. is appended to\n"
"differentiate.\n");
QCoreApplication::instance()->quit();
return;
}
foreach (QString arg, args) {
QUrl url = QUrl::fromEncoded(arg.toLocal8Bit());
doDownload(url);
}
}
void DownloadManager::downloadFinished(QNetworkReply *reply)
{
QUrl url = reply->url();
if (reply->error()) {
fprintf(stderr, "Download of %s failed: %s\n",
url.toEncoded().constData(),
qPrintable(reply->errorString()));
} else {
QString filename = saveFileName(url);
if (saveToDisk(filename, reply))
printf("Download of %s succeded (saved to %s)\n",
url.toEncoded().constData(), qPrintable(filename));
}
currentDownloads.removeAll(reply);
reply->deleteLater();
if (currentDownloads.isEmpty())
// all downloads finished
QCoreApplication::instance()->quit();
}
int main(int argc, char **argv)
{
QCoreApplication app(argc, argv);
DownloadManager manager;
QTimer::singleShot(0, &manager, SLOT(execute()));
app.exec();
}
#include "main.moc"

</source>

==Download manager==

<source lang="cpp">
/****************************************************************************
**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the examples of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial Usage
** Licensees holding valid Qt Commercial licenses may use this file in
** accordance with the Qt Commercial License Agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Nokia.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file. Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain additional
** rights. These rights are described in the Nokia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file. Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
** met: http://www.gnu.org/copyleft/gpl.html.
**
** If you have questions regarding the use of this file, please contact
** Nokia at qt-info@nokia.com.
** $QT_END_LICENSE$
**
****************************************************************************/
#ifndef TEXTPROGRESSBAR_H
#define TEXTPROGRESSBAR_H
#include <QString>
class TextProgressBar
{
public:
TextProgressBar();
void clear();
void update();
void setMessage(const QString &message);
void setStatus(qint64 value, qint64 maximum);
private:
QString message;
qint64 value;
qint64 maximum;
int iteration;
};
#endif

#include "textprogressbar.h"
#include <QByteArray>
#include <stdio.h>
TextProgressBar::TextProgressBar()
: value(0), maximum(-1), iteration(0)
{
}
void TextProgressBar::clear()
{
printf("\n");
fflush(stdout);
iteration = 0;
value = 0;
maximum = -1;
}
void TextProgressBar::update()
{
++iteration;
if (maximum > 0) {
// we know the maximum
// draw a progress bar
int percent = value * 100 / maximum;
int hashes = percent / 2;
QByteArray progressbar(hashes, "#");
if (percent % 2)
progressbar += ">";
printf("\r[%-50s] %3d%% %s ",
progressbar.constData(),
percent,
qPrintable(message));
} else {
// we don"t know the maximum, so we can"t draw a progress bar
int center = (iteration % 48) + 1; // 50 spaces, minus 2
QByteArray before(qMax(center - 2, 0), " ");
QByteArray after(qMin(center + 2, 50), " ");
printf("\r[%s###%s] %s ",
before.constData(), after.constData(), qPrintable(message));
}
}
void TextProgressBar::setMessage(const QString &m)
{
message = m;
}
void TextProgressBar::setStatus(qint64 val, qint64 max)
{
value = val;
maximum = max;
}

#ifndef DOWNLOADMANAGER_H
#define DOWNLOADMANAGER_H
#include <QFile>
#include <QObject>
#include <QQueue>
#include <QTime>
#include <QUrl>
#include <QNetworkAccessManager>
#include "textprogressbar.h"
class DownloadManager: public QObject
{
Q_OBJECT
public:
DownloadManager(QObject *parent = 0);
void append(const QUrl &url);
void append(const QStringList &urlList);
QString saveFileName(const QUrl &url);
signals:
void finished();
private slots:
void startNextDownload();
void downloadProgress(qint64 bytesReceived, qint64 bytesTotal);
void downloadFinished();
void downloadReadyRead();
private:
QNetworkAccessManager manager;
QQueue<QUrl> downloadQueue;
QNetworkReply *currentDownload;
QFile output;
QTime downloadTime;
TextProgressBar progressBar;
int downloadedCount;
int totalCount;
};
#endif

#include "downloadmanager.h"
#include <QFileInfo>
#include <QNetworkRequest>
#include <QNetworkReply>
#include <QString>
#include <QStringList>
#include <QTimer>
#include <stdio.h>
DownloadManager::DownloadManager(QObject *parent)
: QObject(parent), downloadedCount(0), totalCount(0)
{
}
void DownloadManager::append(const QStringList &urlList)
{
foreach (QString url, urlList)
append(QUrl::fromEncoded(url.toLocal8Bit()));
if (downloadQueue.isEmpty())
QTimer::singleShot(0, this, SIGNAL(finished()));
}
void DownloadManager::append(const QUrl &url)
{
if (downloadQueue.isEmpty())
QTimer::singleShot(0, this, SLOT(startNextDownload()));
downloadQueue.enqueue(url);
++totalCount;
}
QString DownloadManager::saveFileName(const QUrl &url)
{
QString path = url.path();
QString basename = QFileInfo(path).fileName();
if (basename.isEmpty())
basename = "download";
if (QFile::exists(basename)) {
// already exists, don"t overwrite
int i = 0;
basename += ".";
while (QFile::exists(basename + QString::number(i)))
++i;
basename += QString::number(i);
}
return basename;
}
void DownloadManager::startNextDownload()
{
if (downloadQueue.isEmpty()) {
printf("%d/%d files downloaded successfully\n", downloadedCount, totalCount);
emit finished();
return;
}
QUrl url = downloadQueue.dequeue();
QString filename = saveFileName(url);
output.setFileName(filename);
if (!output.open(QIODevice::WriteOnly)) {
fprintf(stderr, "Problem opening save file "%s" for download "%s": %s\n",
qPrintable(filename), url.toEncoded().constData(),
qPrintable(output.errorString()));
startNextDownload();
return; // skip this download
}
QNetworkRequest request(url);
currentDownload = manager.get(request);
connect(currentDownload, SIGNAL(downloadProgress(qint64,qint64)),
SLOT(downloadProgress(qint64,qint64)));
connect(currentDownload, SIGNAL(finished()),
SLOT(downloadFinished()));
connect(currentDownload, SIGNAL(readyRead()),
SLOT(downloadReadyRead()));
// prepare the output
printf("Downloading %s...\n", url.toEncoded().constData());
downloadTime.start();
}
void DownloadManager::downloadProgress(qint64 bytesReceived, qint64 bytesTotal)
{
progressBar.setStatus(bytesReceived, bytesTotal);
// calculate the download speed
double speed = bytesReceived * 1000.0 / downloadTime.elapsed();
QString unit;
if (speed < 1024) {
unit = "bytes/sec";
} else if (speed < 1024*1024) {
speed /= 1024;
unit = "kB/s";
} else {
speed /= 1024*1024;
unit = "MB/s";
}
progressBar.setMessage(QString::fromLatin1("%1 %2")
.arg(speed, 3, "f", 1).arg(unit));
progressBar.update();
}
void DownloadManager::downloadFinished()
{
progressBar.clear();
output.close();
if (currentDownload->error()) {
// download failed
fprintf(stderr, "Failed: %s\n", qPrintable(currentDownload->errorString()));
} else {
printf("Succeeded.\n");
++downloadedCount;
}
currentDownload->deleteLater();
startNextDownload();
}
void DownloadManager::downloadReadyRead()
{
output.write(currentDownload->readAll());
}

#include <QCoreApplication>
#include <QStringList>
#include "downloadmanager.h"
#include <stdio.h>
int main(int argc, char **argv)
{
QCoreApplication app(argc, argv);
QStringList arguments = app.arguments();
arguments.takeFirst(); // remove the first argument, which is the program"s name
if (arguments.isEmpty()) {
printf("Qt Download example\n"
"Usage: downloadmanager url1 [url2... urlN]\n"
"\n"
"Downloads the URLs passed in the command-line to the local directory\n"
"If the target file already exists, a .0, .1, .2, etc. is appended to\n"
"differentiate.\n");
return 0;
}
DownloadManager manager;
manager.append(arguments);
QObject::connect(&manager, SIGNAL(finished()), &app, SLOT(quit()));
app.exec();
}

</source>

==QNetworkAccessManager based google suggest==

<source lang="cpp">
/****************************************************************************
**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the examples of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial Usage
** Licensees holding valid Qt Commercial licenses may use this file in
** accordance with the Qt Commercial License Agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Nokia.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file. Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain additional
** rights. These rights are described in the Nokia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file. Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
** met: http://www.gnu.org/copyleft/gpl.html.
**
** If you have questions regarding the use of this file, please contact
** Nokia at qt-info@nokia.com.
** $QT_END_LICENSE$
**
****************************************************************************/
#ifndef GOOGLESUGGEST_H
#define GOOGLESUGGEST_H
#include <QObject>
#include <QNetworkAccessManager>
QT_BEGIN_NAMESPACE
class QLineEdit;
class QNetworkReply;
class QTimer;
class QTreeWidget;
QT_END_NAMESPACE
class GSuggestCompletion : public QObject
{
Q_OBJECT
public:
GSuggestCompletion(QLineEdit *parent = 0);
~GSuggestCompletion();
bool eventFilter(QObject *obj, QEvent *ev);
void showCompletion(const QStringList &choices, const QStringList &hits);
public slots:
void doneCompletion();
void preventSuggest();
void autoSuggest();
void handleNetworkData(QNetworkReply *networkReply);
private:
QLineEdit *editor;
QTreeWidget *popup;
QTimer *timer;
QNetworkAccessManager networkManager;
};
#endif // GOOGLESUGGEST_H

#include <QtCore>
#include <QtGui>
#include <QtNetwork>
#include "googlesuggest.h"
#define GSUGGEST_URL "http://google.com/complete/search?output=toolbar&q=%1"
GSuggestCompletion::GSuggestCompletion(QLineEdit *parent): QObject(parent), editor(parent)
{
popup = new QTreeWidget;
popup->setColumnCount(2);
popup->setUniformRowHeights(true);
popup->setRootIsDecorated(false);
popup->setEditTriggers(QTreeWidget::NoEditTriggers);
popup->setSelectionBehavior(QTreeWidget::SelectRows);
popup->setFrameStyle(QFrame::Box | QFrame::Plain);
popup->setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
popup->header()->hide();
popup->installEventFilter(this);
popup->setMouseTracking(true);
connect(popup, SIGNAL(itemClicked(QTreeWidgetItem*, int)),
SLOT(doneCompletion()));
popup->setWindowFlags(Qt::Popup);
popup->setFocusPolicy(Qt::NoFocus);
popup->setFocusProxy(parent);
timer = new QTimer(this);
timer->setSingleShot(true);
timer->setInterval(500);
connect(timer, SIGNAL(timeout()), SLOT(autoSuggest()));
connect(editor, SIGNAL(textEdited(QString)), timer, SLOT(start()));
connect(&networkManager, SIGNAL(finished(QNetworkReply*)),
this, SLOT(handleNetworkData(QNetworkReply*)));
}
GSuggestCompletion::~GSuggestCompletion()
{
delete popup;
}
bool GSuggestCompletion::eventFilter(QObject *obj, QEvent *ev)
{
if (obj != popup)
return false;
if (ev->type() == QEvent::MouseButtonPress) {
popup->hide();
editor->setFocus();
return true;
}
if (ev->type() == QEvent::KeyPress) {
bool consumed = false;
int key = static_cast<QKeyEvent*>(ev)->key();
switch (key) {
case Qt::Key_Enter:
case Qt::Key_Return:
doneCompletion();
consumed = true;
case Qt::Key_Escape:
editor->setFocus();
popup->hide();
consumed = true;
case Qt::Key_Up:
case Qt::Key_Down:
case Qt::Key_Home:
case Qt::Key_End:
case Qt::Key_PageUp:
case Qt::Key_PageDown:
break;
default:
editor->setFocus();
editor->event(ev);
popup->hide();
break;
}
return consumed;
}
return false;
}
void GSuggestCompletion::showCompletion(const QStringList &choices, const QStringList &hits)
{
if (choices.isEmpty() || choices.count() != hits.count())
return;
const QPalette &pal = editor->palette();
QColor color = pal.color(QPalette::Disabled, QPalette::WindowText);
popup->setUpdatesEnabled(false);
popup->clear();
for (int i = 0; i < choices.count(); ++i) {
QTreeWidgetItem * item;
item = new QTreeWidgetItem(popup);
item->setText(0, choices[i]);
item->setText(1, hits[i]);
item->setTextAlignment(1, Qt::AlignRight);
item->setTextColor(1, color);
}
popup->setCurrentItem(popup->topLevelItem(0));
popup->resizeColumnToContents(0);
popup->resizeColumnToContents(1);
popup->adjustSize();
popup->setUpdatesEnabled(true);
int h = popup->sizeHintForRow(0) * qMin(7, choices.count()) + 3;
popup->resize(popup->width(), h);
popup->move(editor->mapToGlobal(QPoint(0, editor->height())));
popup->setFocus();
popup->show();
}
void GSuggestCompletion::doneCompletion()
{
timer->stop();
popup->hide();
editor->setFocus();
QTreeWidgetItem *item = popup->currentItem();
if (item) {
editor->setText(item->text(0));
QKeyEvent *e;
e = new QKeyEvent(QEvent::KeyPress, Qt::Key_Enter, Qt::NoModifier);
QApplication::postEvent(editor, e);
e = new QKeyEvent(QEvent::KeyRelease, Qt::Key_Enter, Qt::NoModifier);
QApplication::postEvent(editor, e);
}
}
void GSuggestCompletion::preventSuggest()
{
timer->stop();
}
void GSuggestCompletion::autoSuggest()
{
QString str = editor->text();
QString url = QString(GSUGGEST_URL).arg(str);
networkManager.get(QNetworkRequest(QString(url)));
}
void GSuggestCompletion::handleNetworkData(QNetworkReply *networkReply)
{
QUrl url = networkReply->url();
if (!networkReply->error()) {
QStringList choices;
QStringList hits;
QString response(networkReply->readAll());
QXmlStreamReader xml(response);
while (!xml.atEnd()) {
xml.readNext();
if (xml.tokenType() == QXmlStreamReader::StartElement)
if (xml.name() == "suggestion") {
QStringRef str = xml.attributes().value("data");
choices << str.toString();
}
if (xml.tokenType() == QXmlStreamReader::StartElement)
if (xml.name() == "num_queries") {
QStringRef str = xml.attributes().value("int");
hits << str.toString();
}
}
showCompletion(choices, hits);
}
networkReply->deleteLater();
}

#ifndef SEARCHBOX_H
#define SEARCHBOX_H
#include <QLineEdit>
class GSuggestCompletion;
class SearchBox: public QLineEdit
{
Q_OBJECT
public:
SearchBox(QWidget *parent = 0);
protected slots:
void doSearch();
private:
GSuggestCompletion *completer;
};

#endif // SEARCHBOX_H

#include <QDesktopServices>
#include <QUrl>
#include "searchbox.h"
#include "googlesuggest.h"
#define GSEARCH_URL "http://www.google.com/search?q=%1"

SearchBox::SearchBox(QWidget *parent): QLineEdit(parent)
{
completer = new GSuggestCompletion(this);
connect(this, SIGNAL(returnPressed()), SLOT(doSearch()));
setWindowTitle("Search with Google");
adjustSize();
resize(400, height());
setFocus();
}
void SearchBox::doSearch()
{
completer->preventSuggest();
QString url = QString(GSEARCH_URL).arg(text());
QDesktopServices::openUrl(QUrl(url));
}

#include <QApplication>
#include "searchbox.h"
int main(int argc, char * argv[])
{
QApplication app(argc, argv);
SearchBox *searchEdit = new SearchBox;
searchEdit->show();
return app.exec();
}

</source>

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Admin: 1 версия: Импорт контента...