[solved] deal cards and add to the scene

Marcius

Hey guys,

I can't seem to figure out the best way to do this. Here is what I've got (to put it simply):

A Card class that has its suit and rank;
A Deck class made of 32 Cards. In here a Card is assigned a suit and a rank using Card's setter function. Then the Deck is shuffled and Cards dealt to 3 players (using 3 vectors, 10 cards each).

At this stage, Cards are only sets of numbers, i.e. 1/5, 3/4 etc. The first number is a suit (1-4) and the second is a rank (1-8). And that's where I get stuck. How do I incorporate Qt so that every card is assigned its corresponding GIF image (let's say 1/1 would be seven of hearts, 2/2 - eight of diamonds etc) and put in a scene?

SGaist

Hi,

You could use a QMap<QPair<int, int>, QPixmap> that will be your card deck.

Then copy the keys (QList<QPair<int, int>> cards = myMap.keys() and run std::random_shuffle on them.

From there you can create your scene getting the pixmap base on your randomized cards.

Hope it helps.

Marcius

Thank you for your input, SGaist. I'll give it a try and see how far I get with this. Will be back with an update. Meanwhile, if anyone else has any other ideas, that would be greatly appreciated!

Marcius

Marcius

Hey,

After some time playing around, I ended up with this.

My Card class inherits QGraphicsPixmapItem. When deck is created and all the cards get their suits and values, they also get a corresponding picture using setPixmap function. Then I call shuffle and deal functions, the later looks something like this (a loop here to put the cards onto the scene) :

@
QGraphicsPixmapItem *item = new QGraphicsPixmapItem();

item->setPixmap(QPixmap(card[i].pixmap()));
scene.addItem(item);
@

I'm happy with the result so far, but it's not tested fully yet, so don't know if it's going to do exactly what I want.

Please let me know your thoughts.

Thanks!

EDIT:

Although now I think after the cards are put on the screen, they become simply pictures and are not associated with Card class anymore because of this
@ item->setPixmap(QPixmap(card[i].pixmap())); @

Any thoughts on this?

Marcius

Sorry to bombard this thread with questions, but how could I use
@ scene.addItem(item); @ item being my Card object? Since all of them already are QGraphicsPixmapItems and have Qpixmaps assigned. I think that would help me a lot.

SGaist

You could make a subclass of QGraphicsPixmapItem and make it your card e.g. add getters for suit/rank to that subclass

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..