QTextEdit drag and drop problem

[konradm]

Hi everyone! I'm completly new to qt4 and while writng a simple text editor I encountered a problem. I wanted to enable copying and pasting of images in my program. I found a sample code in QTextEdit documentation but I couldn't implement it in my program. I've been trying to figure this out but unfortunatelly without any success. Here is the code(I've pasted only a code which is responsible for drag and drop of images):

//mainwindow.h
class MainWindow : public QMainWindow, private Ui::MainWindow
{
    Q_OBJECT
 
public:
    explicit MainWindow(QWidget *parent = 0);
    void insertFromMimeData( const QMimeData *source );
    bool canInsertFromMimeData( const QMimeData *source ) const;
 
//mainwindow.cpp
bool MainWindow::canInsertFromMimeData( const QMimeData *source ) const
 {
     if (source->hasImage())
         return true;
     else
         return textEdit->canInsertFromMimeData(source);
 }
void MainWindow::insertFromMimeData( const QMimeData *source )
 {
     if (source->hasImage())
     {
         QImage image = qvariant_cast<QImage>(source->imageData());
         QTextCursor cursor = textEdit->textCursor();
         QTextDocument *document = textEdit->document();
         document->addResource(QTextDocument::ImageResource, QUrl("image"), image);
         cursor.insertImage("image");
     }
 }

//mainwindow.h
class MainWindow : public QMainWindow, private Ui::MainWindow
{
    Q_OBJECT

public:
    explicit MainWindow(QWidget *parent = 0);
    void insertFromMimeData( const QMimeData *source );
    bool canInsertFromMimeData( const QMimeData *source ) const;

//mainwindow.cpp
bool MainWindow::canInsertFromMimeData( const QMimeData *source ) const
 {
     if (source->hasImage())
         return true;
     else
         return textEdit->canInsertFromMimeData(source);
 }
void MainWindow::insertFromMimeData( const QMimeData *source )
 {
     if (source->hasImage())
     {
         QImage image = qvariant_cast<QImage>(source->imageData());
         QTextCursor cursor = textEdit->textCursor();
         QTextDocument *document = textEdit->document();
         document->addResource(QTextDocument::ImageResource, QUrl("image"), image);
         cursor.insertImage("image");
     }
 }

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compiler says that this line
return textEdit->canInsertFromMimeData(source);
is wrong. I guess that it's a very simple mistake but I would be really grateful if someone could help me with it.
Cheers!