QGraphicsPathItem Doubt

Hi all

I am having a QGraphicsPathItem which is selectable. I am able to select the item by clicking the area defined by its path. But I would like it to be selectable by clicking any point within its bounding rectangle.

For example, if my shape is circle, I want it to be selected if I click on any point its bounding rectangle.

Any suggestion for how to do this?

Thanks
Arjun

Reimplement the contains function by deriving a class from QGraphicsPathItem like this

Code:

---

class MyPathItem : public QGraphicsPathItem
{
public:
     MyPathItem(const QPainterPath & path, QGraphicsItem * parent = 0 ) : QGraphicsPathItem(path,parent)
     {}
 
      bool contains( const QPointF & point ) const
      {
             return boundingRect().contains(point);
       }
};

---

One more doubt.

I have the QGraphicsPathItem and its bounding rectangle. I want to change the Pen that draws the bounding rectangle when the item is selected. I dont have the paint function. I just use the default implementation as of now.

How to set the pen for drawing the bounding rectangle when the item is selected. Is there a way to use the default implementation and still achieve this?

Thanks
Arjun

Oh you mean the bounding rect is part of the painterpath ? If thats the case you can't achieve what you wanted. You can draw the bounding rect separately. Then you can control its pen like this

Code:

---

MyPathItem::paint(QPainter *p, QStyleOptionGraphicsItem *o, QWidget *w)
{
     QGraphicsPathItem::paint(p,o,w);
     if(o->State & QStyle::State_Selected)
         p->setPen(selectedPen);
     else
         p->setPen(unselectedPen);
     p->drawRect(boundingRect());
}

---

Quote:

---

Oh you mean the bounding rect is part of the painterpath ?

---

No. The bouding rectangle is not part of the painterpath. Its just the QRectF returned by the boudingRect fucntion.

The default paint implemnetation draws it with black pen and dotted lines. I want to chnage this behaviour. So, can I just draw the bounding rect with the new pen over the old one? or can I do it differently?

Thanks a lot
Arjun

In this case , the solution above involving paint event is what you need :)

BTW i had a look at the source code of QPainterPathItem and actually that draws the bounding rect. So the above solution will be drawing the bounding rect twice :)
You can use this hack instead

Code:

---

MyPathItem::paint(QPainter *p, QStyleOptionGraphicsItem *o, QWidget *w)
{
   QStyle::State back = o->state;
   o->state &= ~QStyle::State_Selected;//Removes selection flag
   QGraphicsPathItem::paint(p,o,w);
   o->state = back;
   if(o->state & QStyle::State_Selected)
      p->setPen(selectedPen);
   else
      p->setPen(unselectedPen);
   p->drawRect(boundingRect());
}

---

This is what I wanted. About how to avoid painting the bouding rect twice. Thanks man.

Arjun