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++.