Problem with a cursor during Drag and Drop

[mtrpoland]

Hi,
I have got a tiny problem connected to a drag and drop mechanism.
My QWidget subclass (lets call it A) is intended to be a source of elements that are copied to other type of QWidget subclass(lets call it B), thus in A I reimplement only

void PawnBox::mousePressEvent(QMouseEvent *event) {
	//we do not need to distinguish click from a drag
	//and we implement drag mechanism in a mousePressEvent
	QPoint clickPt = event->pos();
	//we recognize color of the dragged item
	QRect pawnArea = QRect(0,0,20,20);
	int pawnKind = -1; //index of a global pawn vector
	for(int i=0;i<4;++i) {
		pawnArea.setRect(25,45+i*30,20,20);
		if(pawnArea.contains(clickPt)) { pawnKind = i; break; }
		pawnArea.setRect(55,45+i*30,20,20);
		if(pawnArea.contains(clickPt)) { pawnKind = i+4; break; }
	}
		//if a click happened on a non-pawn area we ignore it
	if(pawnKind == -1) return;
	qDebug(qPrintable(QString::number(pawnKind)));
	//we assign the QColor object to a QByteArray
	QByteArray bytes;
	QDataStream out(&bytes,QIODevice::WriteOnly);
	out << internalVectorPtr->at(pawnKind);
	//we pack it
	QMimeData *mimeData = new QMimeData;
	mimeData->setData("qt-class/qcolor", bytes);
	//we prepare cursor graphics
	QPixmap draggedPawnImage = QPixmap(24,24);
	draggedPawnImage.fill(Qt::transparent);
	QPainter pixPainter(&draggedPawnImage);
	Pawn tmpPawn = Pawn(internalVectorPtr->at(pawnKind));
	MTR::Global::paintPawnAt(2,2,tmpPawn,pixPainter);
	//we establish QDrag object, draw cursor and embed data
	QDrag *drag = new QDrag(this);
	drag->setPixmap(draggedPawnImage);
	//QApplication::setOverrideCursor(QCursor(*cursorPx,10,10));
	drag->setDragCursor(*cursorPx,Qt::MoveAction);
	drag->setDragCursor(*cursorPx,Qt::CopyAction);
	drag->setMimeData(mimeData);
	drag->setHotSpot(QPoint(12,12));
	//and we send it
	Qt::DropAction dropAction = drag->exec(Qt::CopyAction,Qt::CopyAction);
	//QApplication::restoreOverrideCursor();
 
}

void PawnBox::mousePressEvent(QMouseEvent *event) {
	//we do not need to distinguish click from a drag
	//and we implement drag mechanism in a mousePressEvent
	QPoint clickPt = event->pos();
	//we recognize color of the dragged item
	QRect pawnArea = QRect(0,0,20,20);
	int pawnKind = -1; //index of a global pawn vector
	for(int i=0;i<4;++i) {
		pawnArea.setRect(25,45+i*30,20,20);
		if(pawnArea.contains(clickPt)) { pawnKind = i; break; }
		pawnArea.setRect(55,45+i*30,20,20);
		if(pawnArea.contains(clickPt)) { pawnKind = i+4; break; }
	}
		//if a click happened on a non-pawn area we ignore it
	if(pawnKind == -1) return;
	qDebug(qPrintable(QString::number(pawnKind)));
	//we assign the QColor object to a QByteArray
	QByteArray bytes;
	QDataStream out(&bytes,QIODevice::WriteOnly);
	out << internalVectorPtr->at(pawnKind);
	//we pack it
	QMimeData *mimeData = new QMimeData;
	mimeData->setData("qt-class/qcolor", bytes);
	//we prepare cursor graphics
	QPixmap draggedPawnImage = QPixmap(24,24);
	draggedPawnImage.fill(Qt::transparent);
	QPainter pixPainter(&draggedPawnImage);
	Pawn tmpPawn = Pawn(internalVectorPtr->at(pawnKind));
	MTR::Global::paintPawnAt(2,2,tmpPawn,pixPainter);
	//we establish QDrag object, draw cursor and embed data
	QDrag *drag = new QDrag(this);
	drag->setPixmap(draggedPawnImage);
	//QApplication::setOverrideCursor(QCursor(*cursorPx,10,10));
	drag->setDragCursor(*cursorPx,Qt::MoveAction);
	drag->setDragCursor(*cursorPx,Qt::CopyAction);
	drag->setMimeData(mimeData);
	drag->setHotSpot(QPoint(12,12));
	//and we send it
	Qt::DropAction dropAction = drag->exec(Qt::CopyAction,Qt::CopyAction);
	//QApplication::restoreOverrideCursor();
	
}

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and everything is fine apart from the fact that over a pawn image instead of a small and transparent dot of *cursorPx initialized in a constructor of A:

//we prepare small point-pixmap which will be our mini cursor when dragging a pawn
	cursorPx = new QPixmap(1,1);
	cursorPx->fill();

//we prepare small point-pixmap which will be our mini cursor when dragging a pawn
	cursorPx = new QPixmap(1,1);
	cursorPx->fill();

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there is Qt::ForbiddenCursor.

How to establish desired cursor during drag and drop?

[jpn]

You'll see a forbidden cursor over everything that does not accept the proposed action of QDragMoveEvent.

void MyWidget::dragMoveEvent(QDragMoveEvent* event)
{
    if (event->mimeData()->hasFormat("qt-class/qcolor"))
        event->acceptProposedAction();
}

void MyWidget::dragMoveEvent(QDragMoveEvent* event)
{
    if (event->mimeData()->hasFormat("qt-class/qcolor"))
        event->acceptProposedAction();
}

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