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How to increment Image name ?

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  • KroMignonK KroMignon

    @jsulm said in How to increment Image name ?:

    The id is comming from https://doc.qt.io/qt-5/qcameraimagecapture.html#imageCaptured

    I see! :D

    So this would also not work!
    Then I don't see another solution as what @jsulm already suggested: use class member to store the counter value

    jsulmJ Offline
    jsulmJ Offline
    jsulm
    Lifetime Qt Champion
    wrote on last edited by
    #13

    @KroMignon said in How to increment Image name ?:

    So this would also not work!

    Actually it should :-)

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

    KroMignonK 1 Reply Last reply
    0
    • jsulmJ jsulm

      @KroMignon said in How to increment Image name ?:

      So this would also not work!

      Actually it should :-)

      KroMignonK Offline
      KroMignonK Offline
      KroMignon
      wrote on last edited by
      #14

      @jsulm said in How to increment Image name ?:

      Actually it should :-)

      Okay, I never used QCameraImageCapture, so I supposed the ID would be the ID of the used camera and not if the image...
      Maybe I should avoid the reply to posts for topics I not experimented in!

      It is an old maxim of mine that when you have excluded the impossible, whatever remains, however improbable, must be the truth. (Sherlock Holmes)

      hamzaelaziziH 1 Reply Last reply
      0
      • KroMignonK KroMignon

        @jsulm said in How to increment Image name ?:

        Actually it should :-)

        Okay, I never used QCameraImageCapture, so I supposed the ID would be the ID of the used camera and not if the image...
        Maybe I should avoid the reply to posts for topics I not experimented in!

        hamzaelaziziH Offline
        hamzaelaziziH Offline
        hamzaelazizi
        wrote on last edited by
        #15

        @KroMignon Sir, your solution helped me, so i think you should keep relying to this kind of posts :D, i have one last question, @jsulm how can i use my own id variable ? should i create a variable inside this class ? i don't understand !

        jsulmJ 1 Reply Last reply
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        • hamzaelaziziH hamzaelazizi

          @KroMignon Sir, your solution helped me, so i think you should keep relying to this kind of posts :D, i have one last question, @jsulm how can i use my own id variable ? should i create a variable inside this class ? i don't understand !

          jsulmJ Offline
          jsulmJ Offline
          jsulm
          Lifetime Qt Champion
          wrote on last edited by
          #16

          @hamzaelazizi said in How to increment Image name ?:

          should i create a variable inside this class ?

          Yes and you initialize it with 0. Each time your slot is called you increment it and check whether it is bigger than the max id value you want to use, if it is you set it back to 0.

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

          hamzaelaziziH 1 Reply Last reply
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          • jsulmJ jsulm

            @hamzaelazizi said in How to increment Image name ?:

            should i create a variable inside this class ?

            Yes and you initialize it with 0. Each time your slot is called you increment it and check whether it is bigger than the max id value you want to use, if it is you set it back to 0.

            hamzaelaziziH Offline
            hamzaelaziziH Offline
            hamzaelazizi
            wrote on last edited by
            #17

            @jsulm something like this ?

            
            QObject::connect(_image_capture.data(), &QCameraImageCapture::imageCaptured, [=] (int id=0, QImage img) {
             int idx = 0;
             if(idx>=11)
             {
                     idx=0;
             }
             else
             {
                     idx++;
             }
              QString fileName = QString::number(idx) + ".png";
              QString path = QStandardPaths::writableLocation(QStandardPaths::PicturesLocation) + "/" + fileName;
              img.save(path, "PNG");
                        });
            

            Because i've tried this and it didn't work :/

            jsulmJ Cobra91151C 2 Replies Last reply
            0
            • hamzaelaziziH hamzaelazizi

              @jsulm something like this ?

              
              QObject::connect(_image_capture.data(), &QCameraImageCapture::imageCaptured, [=] (int id=0, QImage img) {
               int idx = 0;
               if(idx>=11)
               {
                       idx=0;
               }
               else
               {
                       idx++;
               }
                QString fileName = QString::number(idx) + ".png";
                QString path = QStandardPaths::writableLocation(QStandardPaths::PicturesLocation) + "/" + fileName;
                img.save(path, "PNG");
                          });
              

              Because i've tried this and it didn't work :/

              jsulmJ Offline
              jsulmJ Offline
              jsulm
              Lifetime Qt Champion
              wrote on last edited by
              #18

              @hamzaelazizi said in How to increment Image name ?:

              something like this ?

              No.
              In your code idx is a local variable and not a class member...

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

              hamzaelaziziH 1 Reply Last reply
              0
              • hamzaelaziziH hamzaelazizi

                @jsulm something like this ?

                
                QObject::connect(_image_capture.data(), &QCameraImageCapture::imageCaptured, [=] (int id=0, QImage img) {
                 int idx = 0;
                 if(idx>=11)
                 {
                         idx=0;
                 }
                 else
                 {
                         idx++;
                 }
                  QString fileName = QString::number(idx) + ".png";
                  QString path = QStandardPaths::writableLocation(QStandardPaths::PicturesLocation) + "/" + fileName;
                  img.save(path, "PNG");
                            });
                

                Because i've tried this and it didn't work :/

                Cobra91151C Offline
                Cobra91151C Offline
                Cobra91151
                wrote on last edited by
                #19

                @hamzaelazizi

                I have updated my previous post. Please, try it again.

                1 Reply Last reply
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                • jsulmJ jsulm

                  @hamzaelazizi said in How to increment Image name ?:

                  something like this ?

                  No.
                  In your code idx is a local variable and not a class member...

                  hamzaelaziziH Offline
                  hamzaelaziziH Offline
                  hamzaelazizi
                  wrote on last edited by
                  #20

                  @jsulm i see, but whenever i declare a variable outside the method i get this error saying that the variable i created is a Read-only

                  JonBJ jsulmJ 2 Replies Last reply
                  0
                  • hamzaelaziziH hamzaelazizi

                    @jsulm i see, but whenever i declare a variable outside the method i get this error saying that the variable i created is a Read-only

                    JonBJ Offline
                    JonBJ Offline
                    JonB
                    wrote on last edited by
                    #21

                    @hamzaelazizi Depends what you write and where.

                    1 Reply Last reply
                    0
                    • hamzaelaziziH hamzaelazizi

                      @jsulm i see, but whenever i declare a variable outside the method i get this error saying that the variable i created is a Read-only

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

                      @hamzaelazizi said in How to increment Image name ?:

                      outside the method

                      I never suggested to declare it outside of the method. I suggested to declare it as a class member:

                      class YOUR_CLASS:
                      {
                      private:
                          int idx{0};
                      

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

                      hamzaelaziziH 1 Reply Last reply
                      2
                      • jsulmJ jsulm

                        @hamzaelazizi said in How to increment Image name ?:

                        outside the method

                        I never suggested to declare it outside of the method. I suggested to declare it as a class member:

                        class YOUR_CLASS:
                        {
                        private:
                            int idx{0};
                        
                        hamzaelaziziH Offline
                        hamzaelaziziH Offline
                        hamzaelazizi
                        wrote on last edited by
                        #23

                        @jsulm i understand now, thank you for your explanation

                        1 Reply Last reply
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