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can not call function of different class

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  • J JadeN001

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

    JonBJ Offline
    JonBJ Offline
    JonB
    wrote on last edited by JonB
    #12

    @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 1 Reply Last reply
    4
    • 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
          0
          • 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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