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can not call function of different class

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  • J 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.

    JonBJ Offline
    JonBJ Offline
    JonB
    wrote on last edited by JonB
    #14

    @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...)

    J 1 Reply Last reply
    0
    • JonBJ 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...)

      J Offline
      J Offline
      JadeN001
      wrote on last edited by
      #15

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

      1 Reply Last reply
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      • J Offline
        J Offline
        JadeN001
        wrote on last edited by JadeN001
        #16

        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?

        1 Reply Last reply
        0
        • J Offline
          J Offline
          JadeN001
          wrote on last edited by JadeN001
          #17

          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.

          1 Reply Last reply
          1
          • SGaistS Offline
            SGaistS Offline
            SGaist
            Lifetime Qt Champion
            wrote on last edited by
            #18

            Hi,

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

            Interested in AI ? www.idiap.ch
            Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

            aha_1980A J 2 Replies Last reply
            1
            • SGaistS SGaist

              Hi,

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

              aha_1980A Offline
              aha_1980A Offline
              aha_1980
              Lifetime Qt Champion
              wrote on last edited by
              #19

              And why are you using waitForConnected?

              this cannot work. use signals&slots!

              regards

              Qt has to stay free or it will die.

              J 1 Reply Last reply
              1
              • SGaistS SGaist

                Hi,

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

                J Offline
                J Offline
                JadeN001
                wrote on last edited by
                #20

                @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.

                1 Reply Last reply
                0
                • aha_1980A aha_1980

                  And why are you using waitForConnected?

                  this cannot work. use signals&slots!

                  regards

                  J Offline
                  J Offline
                  JadeN001
                  wrote on last edited by
                  #21

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

                  1 Reply Last reply
                  0
                  • SGaistS Offline
                    SGaistS Offline
                    SGaist
                    Lifetime Qt Champion
                    wrote on last edited by
                    #22

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

                    Can you describe what you are exactly trying to build ?

                    Interested in AI ? www.idiap.ch
                    Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

                    J 1 Reply Last reply
                    1
                    • SGaistS 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 ?

                      J Offline
                      J Offline
                      JadeN001
                      wrote on last edited by
                      #23

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

                      0_1530341586271_ju.png

                      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.

                      1 Reply Last reply
                      0
                      • J Offline
                        J Offline
                        JadeN001
                        wrote on last edited by JadeN001
                        #24

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

                        1 Reply Last reply
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