draw point with mouseevent

[konvex]

Hallo, I'm a beginner and use Qt 4.4.3.
I would like to draw a point in a scene when i click in the scene. but my program draws a point without clicking, but the point should appear if i click.
I hope somebody can help me.
Here is my program:

class StarItem : public QGraphicsItem
{
public:
      StarItem( QGraphicsItem *parent = 0 ) : QGraphicsItem(parent) {}
      void paint( QPainter *, const QStyleOptionGraphicsItem *, QWidget *widget=0 );
      QRectF boundingRect() const;
protected:
	void mousePressEvent(QGraphicsSceneMouseEvent *e);
	void mouseMoveEvent(QGraphicsSceneMouseEvent *e);
private:
	QPoint position;
	int posx;
	int posy;
	bool shower;
};

class StarItem : public QGraphicsItem
{
public:
      StarItem( QGraphicsItem *parent = 0 ) : QGraphicsItem(parent) {}
      void paint( QPainter *, const QStyleOptionGraphicsItem *, QWidget *widget=0 );
      QRectF boundingRect() const;
protected:
	void mousePressEvent(QGraphicsSceneMouseEvent *e);
	void mouseMoveEvent(QGraphicsSceneMouseEvent *e);
private:
	QPoint position;
	int posx;
	int posy;
	bool shower;
};

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#include "staritem.h"
 
void StarItem::mousePressEvent(QGraphicsSceneMouseEvent *e)
{
if (e->button() == Qt::LeftButton)
{
shower=true;
QPoint position = e->screenPos();
 
posx = position.x();
posy = position.y();
update();
}
return QGraphicsItem::mousePressEvent(e);
}
 
void StarItem::mouseMoveEvent(QGraphicsSceneMouseEvent *e)
{
position = e->screenPos();
return QGraphicsItem::mouseMoveEvent(e);
}
 
 
void StarItem::paint( QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget )
{
 Q_UNUSED( option );
 Q_UNUSED( widget );
 
 QPen pen(Qt::black, 6, Qt::SolidLine, Qt::RoundCap, Qt::RoundJoin);
 painter->setPen(pen);
 
if(shower=true)
{
painter->drawPoint(posx,posy);
}
 
}
 
QRectF StarItem::boundingRect() const
{
   return QRectF( 0, 0, 100, 100 );
}

#include "staritem.h"

void StarItem::mousePressEvent(QGraphicsSceneMouseEvent *e)
{
if (e->button() == Qt::LeftButton)
{
shower=true;
QPoint position = e->screenPos();

posx = position.x();
posy = position.y();
update();
}
return QGraphicsItem::mousePressEvent(e);
}

void StarItem::mouseMoveEvent(QGraphicsSceneMouseEvent *e)
{
position = e->screenPos();
return QGraphicsItem::mouseMoveEvent(e);
}


void StarItem::paint( QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget )
{
 Q_UNUSED( option );
 Q_UNUSED( widget );

 QPen pen(Qt::black, 6, Qt::SolidLine, Qt::RoundCap, Qt::RoundJoin);
 painter->setPen(pen);

if(shower=true)
{
painter->drawPoint(posx,posy);
}

}

QRectF StarItem::boundingRect() const
{
   return QRectF( 0, 0, 100, 100 );
}

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I have no idea what's wrong...

[draftpunk]

Hi,

I just saw the problem:

if(shower=true)
{
    painter->drawPoint(posx,posy);
}

if(shower=true)
{
    painter->drawPoint(posx,posy);
}

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I think you want:

shower == true

shower == true

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Have fun!

-draftpunk

[konvex]

Thanks for the answer.
but I now the problem, I have to draw in the graphicscene and not in der item...
But I tried another way without solution: Now I try to move a ellipse that is in the scene, but in my program there's a small mistake(I think), what I don't see...
I think it's a mistake in the main function?!
Please help...

main.cpp

int main(int argc,char **argv)
{
   QApplication app(argc,argv);
   QGraphicsScene scene;
   QGraphicsView view;
 
StarItem item(100,100,10,10);
scene.addItem(&item);
 
   view.setGeometry(100, 100, 500, 500);
   view.setScene(&scene);
   view.show();
return app.exec();
}

int main(int argc,char **argv)
{
   QApplication app(argc,argv);
   QGraphicsScene scene;
   QGraphicsView view;

StarItem item(100,100,10,10);
scene.addItem(&item);

   view.setGeometry(100, 100, 500, 500);
   view.setScene(&scene);
   view.show();
return app.exec();
}

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staritem.h

class StarItem : public QGraphicsEllipseItem
{
public:
      StarItem (int x,int y,int w,int h) : QGraphicsEllipseItem (x,y,w,h) {}
protected:
	void mouseMoveEvent(QGraphicsSceneMouseEvent *e);
};

class StarItem : public QGraphicsEllipseItem
{
public:
      StarItem (int x,int y,int w,int h) : QGraphicsEllipseItem (x,y,w,h) {}
protected:
	void mouseMoveEvent(QGraphicsSceneMouseEvent *e);
};

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staritem.cpp

void StarItem::mouseMoveEvent(QGraphicsSceneMouseEvent *e)
{
setRect((e->scenePos().x()),(e->scenePos().y()),10,10);
}

void StarItem::mouseMoveEvent(QGraphicsSceneMouseEvent *e)
{
setRect((e->scenePos().x()),(e->scenePos().y()),10,10);
}

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Thanks for every answer.

[aamer4yu]

what are you trying to achieve ? If you want to move the item, you dont need to code !!
Qt does it for u.. just have a look at QGraphicsItem::setFlag with value QGraphicsItem::ItemIsMovable