Program crashes when adding QGraphicsEllipseItem to the scene

[MongKong]

Hello !!
I'm making a Four In a Row kinda game and i have problem spawning circles. When i press space i create an ellipse but when i try to add the thing to the scene my program just crashes...

This is Player.cpp where an object ( circle ) is created.


This is Zeton.cpp


This are Player's and Zeton's header files


Game.cpp file


Game.h file
sf4.jpg


Any help is appreciated !!!

[tuli]

This doesnt work:

class Player : public QObject, public QGraphicspolygonitem

class Player : public QObject, public QGraphicspolygonitem

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https://doc.qt.io/qt-5/moc.html

Multiple Inheritance Requires QObject to Be First

If you are using multiple inheritance, moc assumes that the first inherited class is a subclass of QObject. Also, be sure that only the first inherited class is a QObject.

so just do

class Player : public QGraphicspolygonitem

class Player : public QGraphicspolygonitem

To copy to clipboard, switch view to plain text mode 

as Qgraphicspolygonitem already inherits qobject.

[Ginsengelf]

This doesnt work:

class Player : public QObject, public QGraphicspolygonitem

class Player : public QObject, public QGraphicspolygonitem

To copy to clipboard, switch view to plain text mode 

https://doc.qt.io/qt-5/moc.html




so just do

class Player : public QGraphicspolygonitem

class Player : public QGraphicspolygonitem

To copy to clipboard, switch view to plain text mode 

as Qgraphicspolygonitem already inherits qobject.

No, it does not. QGraphicspolygonitem inherits QAbstractGraphicsShapeItem which inherits QGraphicsItem, but none of those is a QObject.

Ginsengelf

[MongKong]

I forgot to say that, if i put 'this' as a parameter when creating an object Zeton the circle is spawned, but not on the right position and everytime my "player" moves left or right, circle moves with it aswell.

[anda_skoa]

I'm making a Four In a Row kinda game and i have problem spawning circles. When i press space i create an ellipse but when i try to add the thing to the scene my program just crashes...

Access of invalid pointer?
Where do you set the global "game" variable?

This is Player.cpp where an object ( circle ) is created.

Please don't post screenshots of code, post the code.
It is simple text after all.

The board has code tags which will then take care of the formatting.

Cheers,
_

[MongKong]

anda_skoa

In my previous Thread i posted the code, i forgot about those code tags this time tho, sorry. And after asking that question "Where do you set the global "game" variable?" i realized that i globally defined Game and then i redefined it again in the main function. Now it all works ! thanks !!