Thread Issue

satyanarayana143

Hi Friends,

HttpRequest::HttpRequest(QObject parent) : QObject(parent)
{
Getmgr = new QNetworkAccessManager(this);
QObject::connect(Getmgr, SIGNAL(finished(QNetworkReply)),this, SLOT(GetmanagerFinished(QNetworkReply*)));

Postmgr = new QNetworkAccessManager(this);
QObject::connect(Postmgr, SIGNAL(finished(QNetworkReply*)),this, SLOT(PostmanagerFinished(QNetworkReply*)));

Postmgr2 = new QNetworkAccessManager(this);
QObject::connect(Postmgr2, SIGNAL(finished(QNetworkReply*)),this, SLOT(PostmanagerFinished2(QNetworkReply*)));

// no proxy
QNetworkProxyFactory::setUseSystemConfiguration(true);
Postmgr->setProxy(QNetworkProxy(QNetworkProxy::NoProxy));
Postmgr2->setProxy(QNetworkProxy(QNetworkProxy::NoProxy));
Getmgr->setProxy(QNetworkProxy(QNetworkProxy::NoProxy));


for(int i=0;i<MAX_SCHEDULES;i++)
{
    m_nProcess[i] = new QProcess(this);
}

m_FilesWatcher1 = new QFutureWatcher<void>;

}

HttpRequest::~HttpRequest()
{

}
void HttpRequest::Start_Post_Thread(QString m_nIp,int m_nPort,QString m_nUser,QString m_nPassword)
{
if(m_FilesWatcher1->isRunning() == false)
{
m_FilesWatcher1->setFuture(QtConcurrent::run(this,&HttpRequest::Start_Http_Posting,m_nIp,m_nPort,m_nUser,m_nPassword));
}
}
void HttpRequest::Start_Http_Posting(QString IPAdd2, int Port2, QString username2, QString Password2)
{
while(1)
{
Post_Mobile_Login(IPAdd2,Port2,username2,Password2);
sleep(5);
}
}

void HttpRequest::Post_Mobile_Login(QString IPAdd,int Port,QString username,QString Password)
{
QByteArray loginData;
QString str = "user_name="+username+"&password="+Password;
loginData.append(str);
ServerUrl = "http://"+IPAdd+":"+QString::number(Port);
QUrl request(ServerUrl+"/api/res_users/mobile_login?");
QNetworkRequest r(request);
r.setRawHeader("Content-Type", "application/json");
r.setHeader(QNetworkRequest::ContentTypeHeader,"application/x-www-form-urlencoded;charset=UTF-8");
r.setRawHeader("Connection", "keep-alive");
qDebug().noquote() << "############### loginData: ############"<< ServerUrl << loginData ;
Postmgr->post(r, loginData);
}

This is my code when i run this code i am getting error can anybody tell what is porblem and how to solve

QObject: Cannot create children for a parent that is in a different thread.
(Parent is QNetworkAccessManager(0x562024c20f90), parent's thread is QThread(0x562024c13eb0), current thread is QThread(0x562024c326d0).

Christian Ehrlicher

There is absolutely no need to use a QThread for QNetworkAccessManager operations - they're all asynchron. So just stop using threads until you really need them.
Also why do you create two instances of QNetworkAcessManager and what's the reason for the QProcess instances?

satyanarayana143

becuase i want post every 5sec once two instances for different post.

Christian Ehrlicher

This are still no reasons for two QNetworkAccessManager instances and even not for using QThread.

SGaist

Hi,
To add to @Christian-Ehrlicher points:

@satyanarayana143 said in Thread Issue:

sleep(5);

You're blocking the event loop here so your requests can't be properly handled.

On a side note, QNetworkAccessManager handles up to 6 requests in parallel, after that their are queued for processing on a FIFO basis and as fast as possible. So again, don't involve threads until really necessary.

satyanarayana143

Post_Mobile_Login i want to call from mainc.pp every 5sec so i am using while loop with thread.

Christian Ehrlicher

@satyanarayana143 said in Thread Issue:

i want to call from mainc.pp every 5sec

Use a QTimer instead

J.Hilk

@satyanarayana143 yeah, don't.

You're not programming for a MicroController here, use the tools designed for such things.

QTimer

satyanarayana143

@Christian-Ehrlicher

in main.cpp

this is code

QCoreApplication a(argc, argv);
HttpRequest m_nHttpRequest;
QStringList args = a.arguments();

if (args.count() != 5)
{
    qDebug("Usage: %s <IPAddress> <Port> <Username> <Password>  \n",args.at(0));
    exit(1);
}


//m_nHttpRequest.Post_Mobile_Login(args.at(1),args.at(2).toInt(),args.at(3),args.at(4));
m_nHttpRequest.Start_Post_Thread(args.at(1),args.at(2).toInt(),args.at(3),args.at(4));

if i use timer to call Start_Post_Thread function how to pass arguments for timer signal.

Christian Ehrlicher

@satyanarayana143 said in Thread Issue:

how to pass arguments for timer signal.

There is no need to - you can e.g. pass the paramaeters to HttpRequest via ctor or setter functions - basic c++.