can not call function of different class

[JonB]

@JadeN001
OK, so you do get the qDebug() in on_pushButton_send_clicked() but not the first one even in send_MsgToServer(), right?

[koahnig]

@JadeN001

If you are trying to do an auto-connect through Qt, there might be the parameter missing [see here](lhttps://doc.qt.io/qt-5/qabstractbutton.html#clicked .

Therefore, my hint that you might have received a warning on that.

Also when a program crashes under certain circumstances it is helpful to use the debugger.

[JadeN001]

@JonB yeah. because send_MsgToServer() is getting called.

[JonB]

@JadeN001
Do you have access to and know how to use a debugger, because that's what I would use?

[JadeN001]

@koahnig @JonB I Don't have that much idea about debugger. Is there any alternative solution ?

[jsulm]

@JadeN001 You should really learn to use a debugger. A debugger is one of the most important tools a programmer should use :-)

[JonB]

@JadeN001
As @jsulm has just said, learning to use a debugger will in the long-run be the best time you spent! Just do it soon.

In the meantime, in on_pushButton_send_clicked() just before you try to call mw->send_MsgToServer(send); I'd put in some more qDebug() statements which show some of the properties of your connection object via mw->.... You're looking to just verify that mw is indeed still pointing at some valid connection, just in case.....

[JadeN001]

@JonB @jsulm yeah I really appreciate your suggestion. I will start.
I have checked Value of object "mw" by qDebug(). and It returns proper object value.
something like this :

object :  connection(0x201c0350, name="connection")

I thought that might be the issue is ,the object was not being generated properly.But i was wrong.

[JonB]

@JadeN001
Assuming it really is as you say, and you really have rebuilt your code etc., and you are compiling for/viewing debug, and it's not crashing, it's going to be pretty hard to answer how the line mw->send_MsgToServer(send) could simply "not get executed", without a debugger....

One last thing I can think of, just in case. Your first line in send_MsgToServer() is:

qDebug()<<"in sendmsgserver"<<m_pclientsocket;

Just in case there's some problem serializing m_pclientsocket, temporarily change it to plain:

qDebug()<<"in sendmsgserver"

(I don't think there actually will have been an issue because I think you're only trying to print out the pointer here, but it's worth a try...)

[JadeN001]

@JonB yeah u r right. Here is problem in m_pClientsocket. Thank you for direct me. now, I am trying to solve socket problem

[JadeN001]

I have define m_pClientsocket in constructor of class
but it failed to access in send_MsgToServer().
because ,If I define in constuctor then when formclient class define the object on connection class

FormClient::FormClient(QString name, QWidget *parent) :
    QWidget(parent),
    ui(new Ui::FormClient)
{
    ui->setupUi(this);
    delegate=new mydelegate(this);
    mw=new connection(this);
 
}

At that time value of socket is getting changed.
So the changes it bu moving the

    m_pclientsocket= new QTcpSocket(this);

in to another main function.

 void connection::on_pushButton_connect_clicked()
{
    m_pclientsocket= new QTcpSocket(this);

    ui->textEdit_Sendname->clear();
   m_pclientsocket->connectToHost(ui->textEdit_IP->toPlainText(),quint16(ui->textEdit_Port->toPlainText().toInt()));
   if(m_pclientsocket->waitForConnected(1000)){
   qDebug()<<"connected"<<m_pclientsocket;
   ui->label_connection->setText("Connected to Server");
   }
}

send_MsgToServer() can not access it . where i am wrong.? what could be solution?

[JadeN001]

In send_MsgToServer(). the ans of

void connection::send_MsgToServer(QString msg)
{ 
qDebug()<<"in sendmsgserver"<<m_pclientsocket;
    m_pclientsocket->write(msg.toStdString().c_str());
    qDebug()<<"message sended "<<msg;
}

in sendmsgserver QApplication(0x22fe28)
QIODevice::write (QApplication): device not open

what it is indicating? How can be value of socket be like QApplication.

[SGaist]

Hi,

Why are you creating a new QTcpSocket each time you call on_pushButton_connect_clicked ?

[aha_1980]

And why are you using waitForConnected?

this cannot work. use signals&slots!

regards

[JadeN001]

@SGaist because the Problem i am facing :
if I called new QTcpSocket from constructor,then

FormClient::FormClient(QString name, QWidget *parent) :
    QWidget(parent),
    ui(new Ui::FormClient)
{
    ui->setupUi(this);
    delegate=new mydelegate(this);
    mw=new connection(this);
 
}

this class create QTcpSocket evety time when mw=new connection(this); called.
because of that the void connection::send_MsgToServer(QString msg)
get different value of QTcpsocket.

[JadeN001]

@aha_1980 yeah i will correct it.but my problem is still there.

[SGaist]

Currently, with the code you provided, it seems you already have an architectural problem.

Can you describe what you are exactly trying to build ?

[JadeN001]

@SGaist I am creating one QTableview on clientside.when ever client connected,one editor for chatting will create in that tableview.

If want to send message to John from this editor.but when i send message from particular editor the value of QtcpSocket i am getting is somthing like this "

in sendmsgserver QApplication(0x22fe28)
QIODevice::write (QApplication): device not open

connection.cpp is class where socket is created.
formclient.cpp is class of widgets of chatting.

[JadeN001]

Can anyone suggest me , have I worked in a proper way or not?