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Distinguish between text message and image message sent from server (both encoded in qstring)

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  • V Offline
    V Offline
    Vasudha
    wrote on last edited by
    #11

    Okay So I'm sending msgs like this-

        QFile file(fileName);
        if (!file.open(QFile::ReadOnly)) {
            qDebug() << "Cannot open the selected file";
            return;
        }
        QByteArray block;
        block = file.readAll();
        block.toBase64();
    
        QString message(block);
        QString roomID("rID");
        QString type("image");
        qDebug() << "base64 image- " << message;
    
        QString json = "{\"rid\": \"%1\", \"msg\": \"%2\", \"type\": \"%3\"}";
        json = json.arg(roomID, message, type);
    
        sendMessage("sendMessage", QJsonDocument::fromJson(json.toUtf8()));
    

    And receiving them like-

                QString type = result.value("type").toString();
                QString msg = result.value("msg").toString();
                
                if (type == "image"){
                    QByteArray decodedImage;
                    QByteArray image;
                    QPixmap pixmap;
                    QLabel label;
    
                    decodedImage.append(msg);
                    image = QByteArray::fromBase64(decodedImage);
                    pixmap.loadFromData(image,0,Qt::AutoColor);
                    label.setPixmap(pixmap);
                    label.show();
                 }
    

    But only "����" this is displayed instead of the image.

    VRoninV 1 Reply Last reply
    0
    • SGaistS Offline
      SGaistS Offline
      SGaist
      Lifetime Qt Champion
      wrote on last edited by
      #12

      Use QByteArray directly rather than QString, that will avoid unless conversions.

      Also your label variable only exists for the lifetime of the if block in case of type being image so it won't even be shown.

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

      V 1 Reply Last reply
      4
      • SGaistS SGaist

        Use QByteArray directly rather than QString, that will avoid unless conversions.

        Also your label variable only exists for the lifetime of the if block in case of type being image so it won't even be shown.

        V Offline
        V Offline
        Vasudha
        wrote on last edited by
        #13

        @SGaist After correcting this part too the result was same. I realize I have been mixing QML with QWidgets and that's what is causing problems. Is there any other way of receiving images without using QWidgets?

        1 Reply Last reply
        0
        • SGaistS Offline
          SGaistS Offline
          SGaist
          Lifetime Qt Champion
          wrote on last edited by
          #14

          Do you mean showing images ?

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

          V 1 Reply Last reply
          0
          • V Vasudha

            Okay So I'm sending msgs like this-

                QFile file(fileName);
                if (!file.open(QFile::ReadOnly)) {
                    qDebug() << "Cannot open the selected file";
                    return;
                }
                QByteArray block;
                block = file.readAll();
                block.toBase64();
            
                QString message(block);
                QString roomID("rID");
                QString type("image");
                qDebug() << "base64 image- " << message;
            
                QString json = "{\"rid\": \"%1\", \"msg\": \"%2\", \"type\": \"%3\"}";
                json = json.arg(roomID, message, type);
            
                sendMessage("sendMessage", QJsonDocument::fromJson(json.toUtf8()));
            

            And receiving them like-

                        QString type = result.value("type").toString();
                        QString msg = result.value("msg").toString();
                        
                        if (type == "image"){
                            QByteArray decodedImage;
                            QByteArray image;
                            QPixmap pixmap;
                            QLabel label;
            
                            decodedImage.append(msg);
                            image = QByteArray::fromBase64(decodedImage);
                            pixmap.loadFromData(image,0,Qt::AutoColor);
                            label.setPixmap(pixmap);
                            label.show();
                         }
            

            But only "����" this is displayed instead of the image.

            VRoninV Offline
            VRoninV Offline
            VRonin
            wrote on last edited by
            #15

            @Vasudha said in Distinguish between text message and image message sent from server (both encoded in qstring):

            block.toBase64();

            That is a const method. Do you mean block=block.toBase64();?

            "La mort n'est rien, mais vivre vaincu et sans gloire, c'est mourir tous les jours"
            ~Napoleon Bonaparte

            On a crusade to banish setIndexWidget() from the holy land of Qt

            V 1 Reply Last reply
            2
            • SGaistS SGaist

              Do you mean showing images ?

              V Offline
              V Offline
              Vasudha
              wrote on last edited by
              #16

              @SGaist yes

              1 Reply Last reply
              1
              • VRoninV VRonin

                @Vasudha said in Distinguish between text message and image message sent from server (both encoded in qstring):

                block.toBase64();

                That is a const method. Do you mean block=block.toBase64();?

                V Offline
                V Offline
                Vasudha
                wrote on last edited by
                #17

                @VRonin yeah

                1 Reply Last reply
                1
                • VRoninV Offline
                  VRoninV Offline
                  VRonin
                  wrote on last edited by VRonin
                  #18
                  
                  QFile file(fileName);
                      if (!file.open(QFile::ReadOnly)) {
                          qDebug() << "Cannot open the selected file";
                          return;
                      }
                      const QString block = QString::fromLatin1(file.readAll().toBase64());
                  const QString roomID("rID");
                      const QString type("image")
                  QJsonObject jSonImage;
                  jSonImage.insert("rid",roomID);
                  jSonImage.insert("type",type);
                  jSonImage.insert("msg",block);
                  sendMessage("sendMessage", QJsonDocument(jSonImage));
                  

                  "La mort n'est rien, mais vivre vaincu et sans gloire, c'est mourir tous les jours"
                  ~Napoleon Bonaparte

                  On a crusade to banish setIndexWidget() from the holy land of Qt

                  V 1 Reply Last reply
                  4
                  • VRoninV VRonin
                    
                    QFile file(fileName);
                        if (!file.open(QFile::ReadOnly)) {
                            qDebug() << "Cannot open the selected file";
                            return;
                        }
                        const QString block = QString::fromLatin1(file.readAll().toBase64());
                    const QString roomID("rID");
                        const QString type("image")
                    QJsonObject jSonImage;
                    jSonImage.insert("rid",roomID);
                    jSonImage.insert("type",type);
                    jSonImage.insert("msg",block);
                    sendMessage("sendMessage", QJsonDocument(jSonImage));
                    
                    V Offline
                    V Offline
                    Vasudha
                    wrote on last edited by
                    #19

                    @VRonin This was very smart. The image is being sent successfully but how to show it (at receiving end) without using QWidgets (after decoding it)?

                    1 Reply Last reply
                    1
                    • SGaistS Offline
                      SGaistS Offline
                      SGaist
                      Lifetime Qt Champion
                      wrote on last edited by
                      #20

                      A QtQuick Image element ?

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

                      1 Reply Last reply
                      3
                      • V Offline
                        V Offline
                        Vasudha
                        wrote on last edited by
                        #21

                        Thank you everyone :)

                        1 Reply Last reply
                        1

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