I have this function :
bool TCPClient::sendPacket(Protocol::Packet &packet)
{
if(this->tcpSocket->state() == QAbstractSocket::ConnectedState)
{
std::cout << "writing ..." << std::endl;
std::cout << sizeof(BabelPacket) + packet.dataLength << std::endl;
this->tcpSocket->write((const char *)&packet, sizeof(Protocol::BabelPacket) + packet.dataLength);
return this->tcpSocket->waitForBytesWritten(-1);
}
else
{
std::cout << "socket close" << std::endl;
return false;
}
}
But when I called it, it blocks my GUI.
Have you got an idea how I can make this call non blocking, and still have the readyRead signal triggered ?
Thanks
Related
I'm reimplemented the present method from a QAbstractVideo Surface in order to capture frames from an IP camera.
This is my reimplemented methods (the required ones):
QList<QVideoFrame::PixelFormat> CameraFrameGrabber::supportedPixelFormats(QAbstractVideoBuffer::HandleType handleType) const
{
Q_UNUSED(handleType);
return QList<QVideoFrame::PixelFormat>()
<< QVideoFrame::Format_ARGB32
<< QVideoFrame::Format_ARGB32_Premultiplied
<< QVideoFrame::Format_RGB32
<< QVideoFrame::Format_RGB24
<< QVideoFrame::Format_RGB565
<< QVideoFrame::Format_RGB555
<< QVideoFrame::Format_ARGB8565_Premultiplied
<< QVideoFrame::Format_BGRA32
<< QVideoFrame::Format_BGRA32_Premultiplied
<< QVideoFrame::Format_BGR32
<< QVideoFrame::Format_BGR24
<< QVideoFrame::Format_BGR565
<< QVideoFrame::Format_BGR555
<< QVideoFrame::Format_BGRA5658_Premultiplied
<< QVideoFrame::Format_AYUV444
<< QVideoFrame::Format_AYUV444_Premultiplied
<< QVideoFrame::Format_YUV444
<< QVideoFrame::Format_YUV420P
<< QVideoFrame::Format_YV12
<< QVideoFrame::Format_UYVY
<< QVideoFrame::Format_YUYV
<< QVideoFrame::Format_NV12
<< QVideoFrame::Format_NV21
<< QVideoFrame::Format_IMC1
<< QVideoFrame::Format_IMC2
<< QVideoFrame::Format_IMC3
<< QVideoFrame::Format_IMC4
<< QVideoFrame::Format_Y8
<< QVideoFrame::Format_Y16
<< QVideoFrame::Format_Jpeg
<< QVideoFrame::Format_CameraRaw
<< QVideoFrame::Format_AdobeDng;
}
bool CameraFrameGrabber::present(const QVideoFrame &frame)
{
//qWarning() << "A frame";
if (frame.isValid()) {
//qWarning() << "Valid Frame";
QVideoFrame cloneFrame(frame);
cloneFrame.map(QAbstractVideoBuffer::ReadOnly);
const QImage image(cloneFrame.bits(),
cloneFrame.width(),
cloneFrame.height(),
QVideoFrame::imageFormatFromPixelFormat(cloneFrame .pixelFormat()));
qWarning() << "Is created image NULL?" << image.isNull();
if (!image.isNull())
emit nextFrameAsImage(image);
cloneFrame.unmap();
return true;
}
return false;
}
And this is is how I used it:
grabber = new CameraFrameGrabber(this);
connect(grabber,&CameraFrameGrabber::nextFrameAsImage,this,&QCmaraTest::on_newFrame);
QMediaPlayer *a = new QMediaPlayer(this);
QString url = "http://Admin:1234#10.255.255.67:8008";
a->setMedia(QUrl(url));
a->setVideoOutput(grabber);
a->play();
The problem is that the image that is created is null. As far as I can tell, this can only be because the frame is valid but does not contain data.
Any ideas what the problem could be?
Important Detail: If I set the stream to a QVideoWidget and simply show that, it works just fine.
So I found out what the problem was.
This:
QVideoFrame::imageFormatFromPixelFormat(cloneFrame .pixelFormat())
Was returning invalid format because the IP cam gave the format as a YUV format which QImage can't handle. The solution was to force the format and the only one I found that did not make the program crash was: QImage::Format_Grayscale8.
With that, it worked.
I'm using method QUdpSocket::writeDatagram and sending a lot of data. When the socket is full, the method return -1. Is it possible to do somethind like select() with a QUdpSocket?
while(!counterList.empty())
{
CounterValuePtr value = counterList.dequeue();
if (mUdpSocket->bytesToWrite() <= 1<<13)
{
const QByteArray datagram = toDatagram(*value);
qint64 sentBytes = 0;
try
{
sentBytes = mUdpSocket->writeDatagram(datagram, QHostAddress(mSettings->getConnectionIp()), mSettings->getConnectionPort());
}
catch(...)
{
emit dataLost();
qWarning() << "Exception";
throw;
}
qDebug() << datagram;
if(sentBytes == -1)
{
QString errorMsg = getErrorMsg(WSAGetLastError());
qWarning() << "SocketError (" << mUdpSocket->error() << ") : " << mUdpSocket->errorString() << ". " << errorMsg;
emit dataLost();
}
else if(sentBytes < datagram.size())
{
qWarning() << "Not all data sent";
emit dataLost();
}
else
{
qDebug() << "Counter "<< value->getName() << " sent";
datasent = true;
emit dataSent();
}
}
else
{
qWarning() << "Socket write buffer full. Dropping data.";
emit dataLost();
}
}
Some times, writeDatagram returns -1. When I print the last error with WSAGetLastError it prints the buffer is full.
I have multiples DNS record (MX, CNAME , TXT) and I would like to read the TXT record content.
The lookup() function never emit finished(), I am using this code to test:
QDnsLookup m_dns = new QDnsLookup(this);
connect(m_dns, SIGNAL(finished()), this, SLOT(onHandle()));
m_dns->setType(QDnsLookup::TXT);
m_dns->setName("uol.com.br");
m_dns->lookup();
void Update::onHandle()
{
if (m_dns->error() != QDnsLookup::NoError)
qDebug() << m_dns->error() << m_dns->errorString();
foreach (const QDnsServiceRecord &record, m_dns->serviceRecords())
qDebug() << "Name: " << record.name();
emit handled();
}
If I use a online service to read the record, it works!
The onHandle slot should be looking at m_dns->textRecords(), not m_dns->serviceRecords().
The correct code:
foreach (const QDnsTextRecord &record , m_dns->textRecords()) {
qDebug() << "Values: " << record.values();
qDebug() << "Name: " << record.name();
}
The following code is from an example shows how to use QNetworkAccessManager to download things.
void Downloader::replyFinished (QNetworkReply *reply)
{
if(reply->error())
{
qDebug() << "ERROR!";
qDebug() << reply->errorString();
}
else
{
qDebug() << reply->header(QNetworkRequest::ContentTypeHeader).toString();
qDebug() << reply->header(QNetworkRequest::LastModifiedHeader).toDateTime().toString();
qDebug() << reply->header(QNetworkRequest::ContentLengthHeader).toULongLong();
qDebug() << reply->attribute(QNetworkRequest::HttpStatusCodeAttribute).toInt();
qDebug() << reply->attribute(QNetworkRequest::HttpReasonPhraseAttribute).toString();
QFile *file = new QFile("C:/Qt/Dummy/downloaded.txt");
if(file->open(QFile::Append))
{
file->write(reply->readAll());
file->flush();
file->close();
}
delete file;
}
reply->deleteLater();
}
My question is do we have to call reply->deleteLater(); here? If we don't call it, when we perform QNetworkAccessManager::get() call the second time, will the QNetworkReply* in the slot be the same QNetworkReply* ?
If you don't call deleteLater(), the QNetworkReply object will be leaked and its memory not freed. A second get() call will create a new QNetworkReply object.
I am writing a class to parse Itunes Libray File using QXmlQuery and QT-XSLT.
Here's my sample code:
ItunesLibParser::ItunesLibParser()
{
pathToLib = QString("/Users/rakesh/temp/itunes_xslt/itunes_music_library.xml");
}
void ItunesLibParser::createXSLFile(QFile &inFile)
{
if (inFile.exists()) {
inFile.remove();
}
inFile.open(QIODevice::WriteOnly);
QTextStream out(&inFile);
out << QString("<?xml version=\"1.0\" encoding=\"ISO-8859-1\"?>");
out << QString("<xsl:stylesheet version=\"2.0\" xmlns:xsl=\"http://www.w3.org/1999/XSL/Transform\">");
out << QString("<xsl:output method=\"text\" />");
out << QString("<xsl:template name=\"playlistNames\">");
out << QString("<xsl:value-of select=\"child::integer[preceding-sibling::key[1]='Playlist ID']\"/>");
out << QString("<xsl:text>
</xsl:text>");
out << QString("<xsl:value-of select=\"child::string[preceding-sibling::key[1]='Name']\"/>");
out << QString("<xsl:text>
</xsl:text>");
out << QString("</xsl:template>");
out << QString("<xsl:template match=\"/\">");
out << QString("<xsl:for-each select=\"plist/dict/array/dict\">");
out << QString("<xsl:call-template name=\"playlistNames\"/>");
out << QString("</xsl:for-each>");
out << QString("</xsl:template>");
out << QString("</xsl:stylesheet>");
inFile.close();
return;
}
void ItunesLibParser::dumpPlayList()
{
QXmlQuery query(QXmlQuery::XSLT20);
query.setFocus(QUrl(pathToLib));
QFile xslFile("plist.xsl");
createXSLFile(xslFile);
query.setQuery(QUrl("plist.xsl"));
QStringList* outDump = new QStringList();
query.evaluateTo(outDump);
if(outDump != NULL) {
QStringList::iterator iter = (*outDump).begin();
for (; iter != (*outDump).end();
++iter)
//code flow doesn't come here. It means being() == end()
std::cout << (*iter).toLocal8Bit().constData() << std::endl;
}
return;
}
OutDump here doesn't contain data. While in Shell (xmlpatterns-4.7 mystlye.xsl itunes_music_library.xml ), If I run my Query I get proper output.
Is there anything, wrong I am doing while calling it programatically? I checked out plist.xsl is created properly, but my doubt is whether "/Users/rakesh/temp/itunes_xslt/itunes_music_library.xml" this is getting loaded or not? Or there might be another reasons, I am confused. Is there any experts to throw some light onto problem, I will be glad.
Intead from reading from the file, I read the file into buffer and converted that int string as passed to setquery. That solved the problem.
Here's sample code for those who could face similar problem in future.
void ITunesMlibParser::parsePlayListItemXml(int plistId)
{
QXmlQuery xQuery(QXmlQuery::XSLT20);
QFile inFile("/Users/rakesh/temp/itunes_xslt/itunes_music_library.xml");
if (!inFile.open(QIODevice::ReadOnly)) {
return;
}
QByteArray bArray;
while (!inFile.atEnd()) {
bArray += inFile.readLine();
}
QBuffer xOriginalContent(&bArray);
xOriginalContent.open(QBuffer::ReadWrite);
xOriginalContent.reset();
if (xQuery.setFocus(&xOriginalContent))
std::cout << "File Loaded" << std::endl;
//..
//..
}
Thanks
Rakesh