mouse events handling with QGraphicsItem

[trallallero]

Hallo all,

I have a strange problem with the mouse events handling in QGraphicsView and QGraphicsItem.

I create a:
"class MyGraphicsView : public QGraphicsView"
that has a function called:
"void addButton (tButtonValues& vals);"

void MyGraphicsView::addButton(tButtonValues& vals)
{
 
	MyButton* btn = new MyButton(vals, MyFrame::GetFrame(vals.Owner));
 
	vals.MySelf   = btn;
	if (vals.Owner < 0) // the button has no owner so it has not been added to the scene yet
		m_Scene->addItem(btn);
 
	btn->grabMouse();
}

void MyGraphicsView::addButton(tButtonValues& vals)
{

	MyButton* btn = new MyButton(vals, MyFrame::GetFrame(vals.Owner));

	vals.MySelf   = btn;
	if (vals.Owner < 0) // the button has no owner so it has not been added to the scene yet
		m_Scene->addItem(btn);

	btn->grabMouse();
}

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The problem is that I add 16 buttons to the view but only the last one grabs the mouse.

In MyButton class I have this method:

void MyButton::mouseReleaseEvent ( QGraphicsSceneMouseEvent* event )
{
	printf("mouse RELEASE event - <%i> - <%i>\n", event->pos().toPoint().x(), event->pos().toPoint().y() );
 
	QRect r( mVals.qpPosition, mVals.qsSize );
 
	if ( r.contains(event->pos().toPoint()) )
	{
		puts("OK");
	}
	QGraphicsItem::mouseReleaseEvent(event);
}

void MyButton::mouseReleaseEvent ( QGraphicsSceneMouseEvent* event )
{
	printf("mouse RELEASE event - <%i> - <%i>\n", event->pos().toPoint().x(), event->pos().toPoint().y() );

	QRect r( mVals.qpPosition, mVals.qsSize );

	if ( r.contains(event->pos().toPoint()) )
	{
		puts("OK");
	}
	QGraphicsItem::mouseReleaseEvent(event);
}

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I try to propagate the event to all the other items with a mouseReleaseEvent call but no way, only the last created button gets the call.
Is it a bug or am I doing something wrong ?

Thanks

[scascio]

I am not using grabMouse like you did
but what I read about that is that on widget at a time can grab the mouse.

So I am afraid that you can't do what you want that way.

[trallallero]

I am not using grabMouse like you did
but what I read about that is that on widget at a time can grab the mouse.

So I am afraid that you can't do what you want that way.

Yes, I've just found the problem

grabMouse cannot be used, you're right, but my problem was in boundingRect method.
I returned:

QRectF boundingRect     () const { return QRectF(); }

QRectF boundingRect     () const { return QRectF(); }

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and this of course means that the buttons are 0 sized.

Now I return:

QRectF boundingRect     () const { return QRectF(QPoint(0, 0), mVals.qsSize); }

QRectF boundingRect     () const { return QRectF(QPoint(0, 0), mVals.qsSize); }

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and everything works fine

Thanks anyway.

[trallallero]

I've forgotten on thing:
If these flags are not set, it doesn't work !

setFlags(QGraphicsItem::ItemIsFocusable  | QGraphicsItem::ItemIsSelectable);

setFlags(QGraphicsItem::ItemIsFocusable  | QGraphicsItem::ItemIsSelectable);

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O at least ItemIsSelectable I think.