In QT i have function xyz() and i need to return QImage and QString both?

amarism

In the function xyz(), I am calculating the string value and number of image and I need to return all the value like string and image. So, What I need to take the return type so they will take all value?

 try
    {
        m_ImgPath = Array[i];
        QByteArray m_path = m_ImgPath.toLocal8Bit();
        char* ImagePath = m_path.data();

      obj *m_ThumpDCMReader = obj::New();
        TReader->SetFileName(ImagePath);
        TReader->Update();
        //const QString string = NULL;
        const char *str_uchar = TReader->GetMetaData()->GetAttributeValue(DC::string).GetCharData();
        string = QString::fromUtf8((char *)str_uchar);
        SPointer<ImageData> imageData = TReader->GetOutput();
        if (!imageData) { return QImage(); }

        /// \todo retrieve just the UpdateExtent
        int width = imageData->GetDimensions()[0];
        int height = imageData->GetDimensions()[1];

        QImage image(width, height, QImage::Format_RGB32);
        QRgb *rgbPtr =  reinterpret_cast<QRgb *>(image.bits()) + width * (height - 1);
        unsigned char *colorsPtr = reinterpret_cast<unsigned char *>(imageData->GetScalarPointer());
        for (int row = 0; row < height; row++)
        {
            for (int col = 0; col < width; col++)
            {
                *(rgbPtr++) = QColor(colorsPtr[0], colorsPtr[1], colorsPtr[2]).rgb();
                colorsPtr += imageData->GetNumberOfScalarComponents();
            }

            rgbPtr -= width * 2;
        }
        return (Image,string)
    }
    catch (...) { return QImage(); }
}

SO what I need to add the return type. So, they will return multiple data.

SGaist

Hi,

Either create a small structure containing your data or use std::tuple.

amarism

@SGaistI am using QPair<QString , QImagre> and return qMakePair(string,image);
but the problem is how to receive the qMakePair value ??

SGaist

Right, I forgot about QPair.

It's just:

QPair<QString , QImage> returnValue = xyzy();

amarism

I have one another class, I want to use the value inside the class and I will make QString as string and QImage as image and I want to update the value inside the string and image. How i will update the same value inside it.

mrjj

@amarism
Hi
You need to make access to it in some form or another.
like

#include <QPair>
#include <QDebug>

using MyPair = QPair<QString, QImage >; // to make it better to read
class DataClass {
  MyPair ThePair; // your pair data
 public:
  DataClass() { // constructor. adds something to the pair
    ThePair.first = "first";
    ThePair.second = QImage(); // blank image
  }
  MyPair& getPair() { // access function. returning a reference to the pair
    return ThePair;
  }
};

int main(int argc, char* argv[]) {
  QApplication a(argc, argv);

  DataClass dc;
  MyPair& pair = dc.getPair();
  qDebug() << "org:"  << pair.first;
  // change it
  pair.first = "the string";
  pair.second = QImage();
  qDebug() << "changed:" << pair.first;

output
org: "first"
changed: "the string"