QT Animation

[earendil]

Hi All,

i'm making an applciation where i have to use animation like zoom, and in a first time I used an object Inherits from QGraphicsItem and I used to animate it QGraphicsAnimationItem.
but i learn that if i create an object inherit s from QGraphicsItem i'm not able to use Slot and Signal because it isn't a QObject.
For this i try to inheriths from two classes QObject and QGraphicsItem to have all the features that these classes have but i had a lot of problems. The question is: there's a method like setScaleAt(...) to QWidjet?
Thanks.

[divanov]

Hi All,

i'm making an applciation where i have to use animation like zoom, and in a first time I used an object Inherits from QGraphicsItem and I used to animate it QGraphicsAnimationItem.
but i learn that if i create an object inherit s from QGraphicsItem i'm not able to use Slot and Signal because it isn't a QObject.
For this i try to inheriths from two classes QObject and QGraphicsItem to have all the features that these classes have but i had a lot of problems. The question is: there's a method like setScaleAt(...) to QWidjet?
Thanks.

Why don't you use QGraphicsObject?

[earendil]

Because i don't know that exist a class like it...
I'll try with it...
thanks

[earendil]

Hi follow what you say and now it's ok.
But if I can i would like to do another question.
My code is structured in this way:

QGraphicsScene *scene=new QGraphicsScene(0,0,360,640);
MyQgraphicsObject *myItem=new MyQgraphicsObject;
scene->addItem(myItem);
QGraphicsView *view=new QGraphicsView(scene);

QGraphicsItemAnimation *animation=new QGraphicsItemAnimation;
animation->setItem(myItem);
animation->setTimeLine(timer);
animation->setScaleAt(0.5,0.7,0.7);
timer->start();

It does the trasformation but it does trasformation from up left corner even I would like that It does trasformation from the center of my Item.
I try to use: setItem->setTransformOriginPoint(180,320);
but id doesn't run.

What could i do?

Thanks.

[divanov]

QGraphicsItemAnimation was deprecated in Qt 4.6, you should not use it in newly written code.
http://qt.nokia.com/doc/4.6/animation-overview.html

[earendil]

I see that i should use QPropertyAnimation but into it there is not a method like setScaleAt (present into QGraphicsItemAnimation).
Could you give me some idea?

[divanov]

You are supposed to animate property "scale" of QGraphicsObject.

[earendil]

My QGraphicsObject is a part of chart. When user press zoom in or zoom out button i'd like to create animation of the zoom like QGraphicsItemAnimation did with QTimeLine.
I try to use method setScale() of QGraphicsItem and it runs but i'm not able to create an animation
Have you any suggestions?
Thanks and sorry.

[divanov]

The documentation contains a lot of examples how you can animate a property:
http://qt.nokia.com/doc/4.6/animatio...-qt-properties