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can not call function of different class

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  • JonBJ 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.....

    J Offline
    J Offline
    JadeN001
    wrote on last edited by
    #13

    @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 1 Reply Last reply
    0
    • 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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