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Signal and slot problem

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  • mrjjM mrjj

    @azravian said:
    hi
    first thing to do is to use

    qDebug() <<"con1" << connect(xxx

    for all your connect and check they all return true;

    A Offline
    A Offline
    azravian
    wrote on last edited by
    #3

    @mrjj

    qDebug()<<"Connection Rising edge: "<<connect(GPIO,SIGNAL(RisingEdge()),this,SLOT(inserted()));
        qDebug()<<"Connection falling edge:"<<connect(GPIO,SIGNAL(FallingEdge()),this,SLOT(Removed()));
    

    gives the output

    Connection Rising edge: true
    Connection falling edge: true

    1 Reply Last reply
    0
    • mrjjM Offline
      mrjjM Offline
      mrjj
      Lifetime Qt Champion
      wrote on last edited by mrjj
      #4

      @azravian said:
      ok super so they accept the connect.

      your error is here

      void gpio::ISR()
      {
      gpio GPIO; <<<<<<<<<<<<<< that is not the one u connect !?

      That is not the
      gpio* GPIO=new gpio();
      one :)

      Update:
      So when you do
      GPIO.emit_FallingSignal();
      with your local copy, no signal is sent to mainwin as
      its an other instance than the one you new in main.

      A 1 Reply Last reply
      0
      • mrjjM mrjj

        @azravian said:
        ok super so they accept the connect.

        your error is here

        void gpio::ISR()
        {
        gpio GPIO; <<<<<<<<<<<<<< that is not the one u connect !?

        That is not the
        gpio* GPIO=new gpio();
        one :)

        Update:
        So when you do
        GPIO.emit_FallingSignal();
        with your local copy, no signal is sent to mainwin as
        its an other instance than the one you new in main.

        A Offline
        A Offline
        azravian
        wrote on last edited by
        #5

        @mrjj that's seems to be a problem but if i change my ISR()

        void gpio::ISR()
        {
            gpio* GPIO=new gpio;
            if(gpio::isHIGH())
            {
                qDebug()<<"RISING Interrupt called";
                GPIO->emit_RisingSignal();
            }
        
            else if(gpio::isLOW())
            {
        
                qDebug() <<"FALLING edge";
                GPIO->emit_FallingSignal();
            }
        }
        i have the same problem, it didn't solve the problem/
        
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        • mrjjM Offline
          mrjjM Offline
          mrjj
          Lifetime Qt Champion
          wrote on last edited by
          #6

          but why are u creating a new Object???
          Use the one in/from main.

          That is the one you have connect to mains slots so making a new one
          in that function will not send any signals to main as you do not connect it
          like the other one.

          So just newing the local copy instead, will not make any difference :)

          mrjjM A 2 Replies Last reply
          0
          • mrjjM mrjj

            but why are u creating a new Object???
            Use the one in/from main.

            That is the one you have connect to mains slots so making a new one
            in that function will not send any signals to main as you do not connect it
            like the other one.

            So just newing the local copy instead, will not make any difference :)

            mrjjM Offline
            mrjjM Offline
            mrjj
            Lifetime Qt Champion
            wrote on last edited by
            #7

            @mrjj

            wait, i just saw
            you create a gpio INSIDE gpio ????

            why?

            mrjjM 1 Reply Last reply
            0
            • mrjjM mrjj

              @mrjj

              wait, i just saw
              you create a gpio INSIDE gpio ????

              why?

              mrjjM Offline
              mrjjM Offline
              mrjj
              Lifetime Qt Champion
              wrote on last edited by
              #8

              I would expect

              void gpio::ISR()
              {

              if(gpio::isHIGH())
              {
                  qDebug()<<"RISING Interrupt called";
                  emit_RisingSignal();
              }
              

              No local object of same type! ?

              1 Reply Last reply
              1
              • mrjjM mrjj

                but why are u creating a new Object???
                Use the one in/from main.

                That is the one you have connect to mains slots so making a new one
                in that function will not send any signals to main as you do not connect it
                like the other one.

                So just newing the local copy instead, will not make any difference :)

                A Offline
                A Offline
                azravian
                wrote on last edited by
                #9

                @mrjj Sir, ISR() is a static function. So to access other functions of the class i need to create an object :) thats why i have defined two other function emit_RisingEdge() and emit_FallingEdge() so i can emit my signals independent of any object.

                1 Reply Last reply
                0
                • ? Guest
                  mrjjM Offline
                  mrjjM Offline
                  mrjj
                  Lifetime Qt Champion
                  wrote on last edited by
                  #10

                  Ok, if u create a instance for use with signals, then its fine.
                  You just need to connect this new object to the slots again.

                  A 1 Reply Last reply
                  1
                  • mrjjM mrjj

                    Ok, if u create a instance for use with signals, then its fine.
                    You just need to connect this new object to the slots again.

                    A Offline
                    A Offline
                    azravian
                    wrote on last edited by
                    #11

                    @mrjj thanks but i'm pretty much beginner with signals and slots,where do i need to change my code

                    mrjjM 1 Reply Last reply
                    0
                    • A azravian

                      @mrjj thanks but i'm pretty much beginner with signals and slots,where do i need to change my code

                      mrjjM Offline
                      mrjjM Offline
                      mrjj
                      Lifetime Qt Champion
                      wrote on last edited by
                      #12

                      @azravian
                      Hi,
                      void gpio::ISR()
                      {
                      gpio* GPIO=new gpio;
                      // here u need to connect again
                      // since its not pr type, but pr instance
                      // so the connect u made in main, are not on GPIO here

                      A 1 Reply Last reply
                      1
                      • mrjjM mrjj

                        @azravian
                        Hi,
                        void gpio::ISR()
                        {
                        gpio* GPIO=new gpio;
                        // here u need to connect again
                        // since its not pr type, but pr instance
                        // so the connect u made in main, are not on GPIO here

                        A Offline
                        A Offline
                        azravian
                        wrote on last edited by
                        #13

                        @mrjj thank you it worked thank you so much Sir :)

                        mrjjM 1 Reply Last reply
                        1
                        • A azravian

                          @mrjj thank you it worked thank you so much Sir :)

                          mrjjM Offline
                          mrjjM Offline
                          mrjj
                          Lifetime Qt Champion
                          wrote on last edited by
                          #14

                          @azravian
                          Super, np :)
                          sorry I missed ur static function. The scroll area is so tiny .)

                          A 1 Reply Last reply
                          1
                          • mrjjM mrjj

                            @azravian
                            Super, np :)
                            sorry I missed ur static function. The scroll area is so tiny .)

                            A Offline
                            A Offline
                            azravian
                            wrote on last edited by
                            #15

                            @mrjj
                            Oh it's Ok sir, thanks Again for your input and help :) I've surely learned a lot

                            1 Reply Last reply
                            1
                            • SGaistS Offline
                              SGaistS Offline
                              SGaist
                              Lifetime Qt Champion
                              wrote on last edited by
                              #16

                              Hi,

                              Just one thing, you have now a memory leak.

                              But in any case, I must say I don't see any reason for making all these methods static.

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

                              mrjjM A 2 Replies Last reply
                              1
                              • SGaistS SGaist

                                Hi,

                                Just one thing, you have now a memory leak.

                                But in any case, I must say I don't see any reason for making all these methods static.

                                mrjjM Offline
                                mrjjM Offline
                                mrjj
                                Lifetime Qt Champion
                                wrote on last edited by
                                #17

                                @SGaist
                                Thank champ. In the static heat, i completely missed that.

                                @azravian
                                You should have a
                                delete GPIO in the end of the function or even better
                                just go back to using the stack again. (so it cleans it self)
                                void gpio::ISR()
                                {
                                gpio GPIO;

                                A 2 Replies Last reply
                                1
                                • mrjjM mrjj

                                  @SGaist
                                  Thank champ. In the static heat, i completely missed that.

                                  @azravian
                                  You should have a
                                  delete GPIO in the end of the function or even better
                                  just go back to using the stack again. (so it cleans it self)
                                  void gpio::ISR()
                                  {
                                  gpio GPIO;

                                  A Offline
                                  A Offline
                                  azravian
                                  wrote on last edited by azravian
                                  #18

                                  @mrjj @SGaist
                                  Yes i noticed it later and have deleted it. thanks again sir

                                  1 Reply Last reply
                                  1
                                  • SGaistS SGaist

                                    Hi,

                                    Just one thing, you have now a memory leak.

                                    But in any case, I must say I don't see any reason for making all these methods static.

                                    A Offline
                                    A Offline
                                    azravian
                                    wrote on last edited by
                                    #19

                                    @SGaist thank you for it :) and the point od making these methods statics is that i am using wiringPi library which need a function as a parameter so i need make it static.

                                    jsulmJ 1 Reply Last reply
                                    0
                                    • A azravian

                                      @SGaist thank you for it :) and the point od making these methods statics is that i am using wiringPi library which need a function as a parameter so i need make it static.

                                      jsulmJ Offline
                                      jsulmJ Offline
                                      jsulm
                                      Lifetime Qt Champion
                                      wrote on last edited by
                                      #20

                                      @azravian In this case you could add a public static method to get the pointer to the gpio instance (basically you create a singleton):

                                      class gpio : public QObject
                                      {
                                          Q_OBJECT
                                      public:
                                          gpio(): instancePtr(nullptr) {}
                                          static gpio* instance()
                                          {
                                              if (!instancePtr) instancePtr = new gpio();
                                              return instancePtr;
                                          }
                                      private:
                                          gpio* instancePtr;
                                      

                                      You can use this method in main to setup the connection and in static methods in gpio to get the pointer to the instance. Don't forget to delete the instance later.

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

                                      1 Reply Last reply
                                      0
                                      • SGaistS Offline
                                        SGaistS Offline
                                        SGaist
                                        Lifetime Qt Champion
                                        wrote on last edited by
                                        #21

                                        @jsulm you forgot to also make instancePtr static. However, I don't think the singleton pattern should be applied here.

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

                                        jsulmJ 1 Reply Last reply
                                        0
                                        • SGaistS SGaist

                                          @jsulm you forgot to also make instancePtr static. However, I don't think the singleton pattern should be applied here.

                                          jsulmJ Offline
                                          jsulmJ Offline
                                          jsulm
                                          Lifetime Qt Champion
                                          wrote on last edited by
                                          #22

                                          @SGaist Yes, I forgot, thanks for pointing :-)

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

                                          1 Reply Last reply
                                          0

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