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can not call function of different class

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  • J JadeN001

    @koahnig program runs properly. But when function send_MsgToServer called.It stopped working.

    JonBJ Offline
    JonBJ Offline
    JonB
    wrote on last edited by
    #4

    @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 1 Reply Last reply
    0
    • 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
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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
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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
                          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
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