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can not call function of different class

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  • JonBJ JonB

    @JadeN001
    You have several qDebug() messages, including 2 in send_MsgToServer(). Do you think it would help us if you told us which ones produced any output (or state that none did), or would you like us to guess?

    J Offline
    J Offline
    JadeN001
    wrote on last edited by
    #5

    @JonB none of the qDebug() of send_MsgToServer() function works. I mean send_MsgToServer() is not getting called.
    And formclient() is called from delegate's create editor().Is there amy connection with issue?

    JonBJ K 2 Replies Last reply
    1
    • J JadeN001

      @JonB none of the qDebug() of send_MsgToServer() function works. I mean send_MsgToServer() is not getting called.
      And formclient() is called from delegate's create editor().Is there amy connection with issue?

      JonBJ Offline
      JonBJ Offline
      JonB
      wrote on last edited by
      #6

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

      J 1 Reply Last reply
      1
      • J JadeN001

        @JonB none of the qDebug() of send_MsgToServer() function works. I mean send_MsgToServer() is not getting called.
        And formclient() is called from delegate's create editor().Is there amy connection with issue?

        K Offline
        K Offline
        koahnig
        wrote on last edited by
        #7

        @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.

        Vote the answer(s) that helped you to solve your issue(s)

        1 Reply Last reply
        2
        • JonBJ JonB

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

          J Offline
          J Offline
          JadeN001
          wrote on last edited by
          #8

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

          JonBJ 1 Reply Last reply
          0
          • J JadeN001

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

            JonBJ Offline
            JonBJ Offline
            JonB
            wrote on last edited by
            #9

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

            1 Reply Last reply
            1
            • J Offline
              J Offline
              JadeN001
              wrote on last edited by
              #10

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

              jsulmJ JonBJ 2 Replies Last reply
              0
              • J JadeN001

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

                jsulmJ Offline
                jsulmJ Offline
                jsulm
                Lifetime Qt Champion
                wrote on last edited by
                #11

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

                https://forum.qt.io/topic/113070/qt-code-of-conduct

                1 Reply Last reply
                4
                • 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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