[solved] deal cards and add to the scene

Marcius

Pardon my ignorance (I'm still very new to C++), but when you say 'make a subclass of QGraphicsPixmapItem' is it
@ class Card : public QGraphicsPixmapItem @
or the other way around? And what is a difference? I tried the first one and it didn't work the way I wanted to, or I did something wrong. By the way, my original Card class has its setter and getter methods.

Thanks a lot for your help!

SGaist

Yes, it's that.

What didn't work the way you wanted ?

Marcius

Oh, sorry, I simply forgot to pass my Card object as a reference to addItem, it seems to be working now.

Ok, so I've got a couple of cards on the screen now and a mouse press event, that looks like this:
@
void Card::mousePressEvent(QGraphicsSceneMouseEvent *Card)
{
qDebug() << "I clicked a card ";
}
@

This is only for testing at the moment. Now, when I click on a Card, I'd like qDebug() to output its suit and value. As I mentioned before, I do have getter methods for that, but not too sure where to go from here.

Again, much appreciated, SGaist!

SGaist

It should rather be:

@
void Card::mousePressEvent(QGraphicsSceneMouseEvent *event) <- here
{
qDebug() << "I clicked a card ";
}@

Marcius

There's still heaps of work left to be done, but you, sir, got me helluva closer :)

Thank you!

SGaist

You're welcome !

Don't hesitate to take some times to look at Qt's documentation examples. They might contain a lot of stuff you can reuse/get inspiration from for your application

Happy coding !

Marcius

Hi,

Not too happy about coming back to the same thread, but I'm facing an issue.

@
class Card : public QGraphicsPixmapItem
@

This line generates a C2248 error, saying I cannot access private member in a QGraphicsPixmapItem class.

I have only a slight idea as to why this happens, but unfortunately no clue what to do about it. Funny thing is, it compiled no problem before, although I haven't made any changes to the Card class or any other relevant part of the code..

SGaist

What's the exact error you are getting ?

Marcius

error C2248: 'QGraphicsPixmapItem::QGraphicsPixmapItem' : cannot access private member declared in class 'QGraphicsPixmapItem'

error C2248: 'QGraphicsPixmapItem::operator =' : cannot access private member declared in class 'QGraphicsPixmapItem'

And that's compiler's output:

1> c:\qt\5.2.1\msvc2012\include\qtwidgets\qgraphicsitem.h(866) : see declaration of 'QGraphicsPixmapItem::QGraphicsPixmapItem'
1> c:\qt\5.2.1\msvc2012\include\qtwidgets\qgraphicsitem.h(822) : see declaration of 'QGraphicsPixmapItem'
1> This diagnostic occurred in the compiler generated function 'Card::Card(const Card &)'

and

'Card &Card::operator =(const Card &)'

Marcius

I can't believe I did it (given my almost non-existent experience), but I finally got rid of the errors by providing my own class copy and assignment operator constructors. Please keep tuned though, will see where it leads me to.. :)

SGaist

What you are doing is risky, you've got the error because the base class (QGraphicsPixmapItem ) explicitly forbids the copy.

If you look at QGraphicsScene you see that you addItem takes a pointer to an item

Marcius

I see what you're saying. I actually may be having problems because of that at the moment (not sure yet though). How would you go about this issue then? Quite frankly, I still don't know which which part of my program causes the error.

SGaist

Just allocate your Cards on the heap and not on the stack

Marcius

I tried that, although I still can't remove copy and assignment operator constructors without getting the same error..

SGaist

Because somewhere in your code you are doing a copy. Are you using a QList<Card> or something similar ?

Marcius

I saw your reply in my other post and I indeed did do copies by using vector. I'm changing my code around now.

Check this line @ vector<Card*> * player = new vector<Card*>; @ Is it correct? And if so, how do I iterate through player? I'm getting a little confused with all these pointers.

SGaist

Just use vector<Card *> player, there's no need of a pointer for the vector

Marcius

@
for (vector<Card*>::iterator iter = player.begin();
iter != player.end(); ++iter)
{
qDebug() << iter->GetSuit()
}
@

How do I call GetSuit() function? This is obviously incorrect

SGaist

With

@(*iter)->GetSuit();@

You should be good

Marcius

Tried it before I asked :) But I get an error: "expression must have pointer-to-class type"