Fix warning C4512 on Visual Studio for DICOM widgets

Example of warning message:
warning C4512: 'ctkThumbnailListWidgetPrivate' : assignment operator could not be generated

Libs/DICOM/Widgets/ctkDICOMAppWidget.cpp

@@ -372,6 +372,7 @@ void ctkDICOMAppWidget::resetModel()
 //----------------------------------------------------------------------------
 void ctkDICOMAppWidget::onProgress(int progress)
 {
+  Q_UNUSED(progress);
   QApplication::processEvents();
 }
 

Libs/DICOM/Widgets/ctkDICOMDatasetView.cpp

@@ -54,10 +54,6 @@ class ctkDICOMDatasetViewPrivate
 
   Q_DECLARE_PUBLIC( ctkDICOMDatasetView );
 
-protected:
-
-  ctkDICOMDatasetView* const q_ptr;
-
 public:
 
   ctkDICOMDatasetViewPrivate( ctkDICOMDatasetView& object );
@@ -77,6 +73,12 @@ public:
   void onStudyModelSelected(const QModelIndex& index);
   void onSeriesModelSelected(const QModelIndex& index);
   void onImageModelSelected(const QModelIndex& index);
+
+protected:
+  ctkDICOMDatasetView* const q_ptr;
+
+private:
+  Q_DISABLE_COPY( ctkDICOMDatasetViewPrivate );
 };
 
 //--------------------------------------------------------------------------

Libs/DICOM/Widgets/ctkDICOMImage.cpp

@@ -38,29 +38,23 @@ struct Node;
 class ctkDICOMImagePrivate
 {
   Q_DECLARE_PUBLIC(ctkDICOMImage);
-protected:
-  ctkDICOMImage* const q_ptr;
-  
 public:
   ctkDICOMImagePrivate(ctkDICOMImage&);
-  virtual ~ctkDICOMImagePrivate();
 
   ::DicomImage* DicomImage;
-};
 
-//------------------------------------------------------------------------------
-ctkDICOMImagePrivate::ctkDICOMImagePrivate(ctkDICOMImage& o):q_ptr(&o)
-{
+protected:
+  ctkDICOMImage* const q_ptr;
 
-}
+private:
+  Q_DISABLE_COPY(ctkDICOMImagePrivate);
+};
 
 //------------------------------------------------------------------------------
-ctkDICOMImagePrivate::~ctkDICOMImagePrivate()
+ctkDICOMImagePrivate::ctkDICOMImagePrivate(ctkDICOMImage& o):q_ptr(&o)
 {
-
 }
 
-
 //------------------------------------------------------------------------------
 ctkDICOMImage::ctkDICOMImage(DicomImage* dicomImage, QObject* parentValue)
   : d_ptr(new ctkDICOMImagePrivate(*this))

Libs/DICOM/Widgets/ctkDICOMThumbnailGenerator.cpp

@@ -36,12 +36,16 @@ struct Node;
 class ctkDICOMThumbnailGeneratorPrivate
 {
   Q_DECLARE_PUBLIC(ctkDICOMThumbnailGenerator);
-protected:
-  ctkDICOMThumbnailGenerator* const q_ptr;
 
 public:
   ctkDICOMThumbnailGeneratorPrivate(ctkDICOMThumbnailGenerator&);
   virtual ~ctkDICOMThumbnailGeneratorPrivate();
+
+protected:
+  ctkDICOMThumbnailGenerator* const q_ptr;
+
+private:
+  Q_DISABLE_COPY( ctkDICOMThumbnailGeneratorPrivate );
 };
 
 //------------------------------------------------------------------------------

Libs/DICOM/Widgets/ctkDICOMThumbnailListWidget.cpp

@@ -60,6 +60,7 @@ Q_DECLARE_METATYPE(QPersistentModelIndex);
 //----------------------------------------------------------------------------
 class ctkDICOMThumbnailListWidgetPrivate : ctkThumbnailListWidgetPrivate
 {
+  Q_DECLARE_PUBLIC(ctkDICOMThumbnailListWidget);
 public:
   typedef ctkThumbnailListWidgetPrivate Superclass;
 
@@ -74,7 +75,8 @@ public:
   void onStudyModelSelected(const QModelIndex &index);
   void onSeriesModelSelected(const QModelIndex &index);
 
-  Q_DECLARE_PUBLIC(ctkDICOMThumbnailListWidget);
+private:
+  Q_DISABLE_COPY( ctkDICOMThumbnailListWidgetPrivate );
 };
 
 //----------------------------------------------------------------------------

Libs/Widgets/ctkThumbnailListWidget_p.h

@@ -31,8 +31,6 @@ class ctkThumbnailListWidget;
 class CTK_WIDGETS_EXPORT ctkThumbnailListWidgetPrivate : public Ui_ctkThumbnailListWidget
 {
   Q_DECLARE_PUBLIC(ctkThumbnailListWidget);
-protected:
-  ctkThumbnailListWidget* const q_ptr;
 public:
   ctkThumbnailListWidgetPrivate(ctkThumbnailListWidget* parent);
 
@@ -43,6 +41,12 @@ public:
 
   int CurrentThumbnail;
   QSize ThumbnailSize;
+
+protected:
+  ctkThumbnailListWidget* const q_ptr;
+
+private:
+  Q_DISABLE_COPY( ctkThumbnailListWidgetPrivate );
 };
 
 #endif