qtconcurent imagescaling example upgrade

[codebehind]

hello.

i look at the example "imagescaling" and done some upgrade.

well:

image.h (image.cpp has all the implementation)

class ImageData
{
  //... some data for the image size and path
}
 
class MyImage: public QWidget, public ImageData
{
// some function for working with images
}

class ImageData
{
  //... some data for the image size and path
}

class MyImage: public QWidget, public ImageData
{
// some function for working with images
}

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Then I have another class for working with all loaded images.

imagelist.h

class MyLsit:public QWidget
{
//...
}

class MyLsit:public QWidget
{
//...
}

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imageList.cpp

// my function for loading image
MyImage loadImage(const ImageData &data)
{
 MyImage m;
//... things to do on loading images
 return m;
}
 
void MyList::FirstStep()
{
 QList<ImageData> datalist;
 // load data
collection= new QFutureWatcher<Image>((QObject*)this);
collection->setFuture(QtConcurrent::mapped(datalist,loadImage));
// etc
}

// my function for loading image
MyImage loadImage(const ImageData &data)
{
 MyImage m;
//... things to do on loading images
 return m;
}

void MyList::FirstStep()
{
 QList<ImageData> datalist;
 // load data
collection= new QFutureWatcher<Image>((QObject*)this);
collection->setFuture(QtConcurrent::mapped(datalist,loadImage));
// etc
}

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when I compile the project it returns the error:

/usr/lib64/qt-4.4.1/include/QtGui/qwidget.h: In copy constructor ‘MyImage::MyImage(const MyImage&)’:
/usr/lib64/qt-4.4.1/include/QtGui/qwidget.h:750: error: ‘QWidget::QWidget(const QWidget&)’ is private
../qt4/Tools/ShowImg/image.h:18: error: within this context
../qt4/Tools/imgsched.cpp: In function ‘Image LoadImage(ImageData&)’:
../qt4/Tools/imgsched.cpp:12: note: synthesized method ‘MyImage::MyImage(const MyImage&)’ first required here

if I change MyImage with QImage:

QImage loadImage(const ImageData &data){...}

QImage loadImage(const ImageData &data){...}

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it compiles.

I think this is an C++ feature, but i can not work it out.
Any suggestion on how to implement this would be appreciate.
thx!