QGraphicsItem::itemIsMovable

[steg90]

Hi,

As part of my derived QGraphicsItem class I override the paint event to draw my object. I thought by setting the itemIsMovable flag would allow the item to be moved when user clicks and drags it? Am I missing something? Do I have to do more work in the paint event to allow the item to be moved?

Here is the code for the class :

class CCanGraphicsItem : public QGraphicsItem
{
public:
	CCanGraphicsItem( int x, int y, QString strText ) : m_rect( 10, 10, 200, 100 ), m_color( QColor(255,255,255,255) )
	{
		m_strText = strText;
		setPos( x, y );
		m_pFont = new QFont("Times", 20, QFont::Bold );
		setFlag(QGraphicsItem::ItemIsMovable, true);
		setFlag(QGraphicsItem::ItemIsSelectable, true);
	}
	void paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget) 
	{
		//  painter->setRenderHint(QPainter::Antialiasing, true);
		painter->setFont( *m_pFont );
		painter->setPen(Qt::SolidLine);
		painter->setBrush(m_color);
		painter->drawRoundRect( m_rect );//10, 10, 100, 100);
		painter->drawText( 20, 20, 190, 90, Qt::AlignCenter, m_strText );//, m_rect );
	}
 
	QRectF boundingRect() const { return m_rect; }
 
protected:
	void mouseDoubleClickEvent ( QGraphicsSceneMouseEvent * event ) 
	{
		QMessageBox::information(0, "Debug", m_strText );
 
	}
 
    void contextMenuEvent(QContextMenuEvent *event)
	{
	}
 
	QRectF m_rect;
	QColor m_color;
	QString m_strText;
	QFont* m_pFont;
};

class CCanGraphicsItem : public QGraphicsItem
{
public:
	CCanGraphicsItem( int x, int y, QString strText ) : m_rect( 10, 10, 200, 100 ), m_color( QColor(255,255,255,255) )
	{
		m_strText = strText;
		setPos( x, y );
		m_pFont = new QFont("Times", 20, QFont::Bold );
		setFlag(QGraphicsItem::ItemIsMovable, true);
		setFlag(QGraphicsItem::ItemIsSelectable, true);
	}
	void paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget) 
	{
		//  painter->setRenderHint(QPainter::Antialiasing, true);
		painter->setFont( *m_pFont );
		painter->setPen(Qt::SolidLine);
		painter->setBrush(m_color);
		painter->drawRoundRect( m_rect );//10, 10, 100, 100);
		painter->drawText( 20, 20, 190, 90, Qt::AlignCenter, m_strText );//, m_rect );
	}

	QRectF boundingRect() const { return m_rect; }
 
protected:
	void mouseDoubleClickEvent ( QGraphicsSceneMouseEvent * event ) 
	{
		QMessageBox::information(0, "Debug", m_strText );
		
	}

    void contextMenuEvent(QContextMenuEvent *event)
	{
	}

	QRectF m_rect;
	QColor m_color;
	QString m_strText;
	QFont* m_pFont;
};

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Regards,
Steve

[steg90]

Hi,

Seems that if I move the itemIsMovable into the paint event it works...

[wysota]

It'd be nice if you called base class implementations of events from within your event handlers. Otherwise it doesn't really matter what flags you set if Qt can't process them.