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[SOLVED] Problems animating QGraphicsProxyWidget



  • Hi All,

    I'm trying to animate a push button I have in my scene.
    I want the button to become visible with an animation when the mouse enters the scene (essentially gradually changing the opacity of the button from 0 to 1)

    The QPropertyAnimation class seems to be exactly what I need but it is not working with QGraphicsProxyWidget.
    This is the way I'm creating the button when I initialize the interface of the QGraphicsView

    @void MyQGraphicsView::buildInterface(){
    ....
    myButton = new QPushButton(this); // myButton member QPushButton variable
    myButtonProxy = scene()->addWidget(myButton); // myButtonProxy member QGraphicsProxyWidget variable
    ...
    }

    void MyQGraphicsView::enterEvent( QEvent * )
    {
    QPropertyAnimation *animation = new QPropertyAnimation(myButtonProxy, "opacity");
    animation->setDuration(1000);

    animation->setStartValue(0);
    animation->setEndValue(1);
    
    animation->start(QAbstractAnimation::DeleteWhenStopped);
    

    }@

    The animation has no effect on the opacity of the button. I also tried for test to modify with an animation the position of the button. Well If I create the QPropertyAnimation using the proxy widget then the animation is not working, if I create it using the button itsself then the animation is working (see example below)

    @void MyQGraphicsView::enterEvent( QEvent * )
    {
    // QPropertyAnimation *animation = new QPropertyAnimation(myButtonProxy, "pos"); // DOES NOT WORK
    QPropertyAnimation *animation = new QPropertyAnimation(myButton, "pos");
    animation->setDuration(1000);

    animation->setStartValue(QPointF(0,0));
    animation->setEndValue(QPointF(scene()->width()/2, scene()->height()/2));
    
    animation->start(QAbstractAnimation::DeleteWhenStopped);
    

    }@

    I'm using Qt 4.7.3
    Do you have any idea how to fix this issue?

    Thanks in advance,
    Calogero



  • i think, you should not give a parent object when creating QPushButton;
    like,

    myButton = new QPushButton();
    (not, myButton = new QPushButton(this);)

    embeded widget will be destroyed when proxy is being destructed (by QGraphicsProxyWidget documentation)



  • thank you very much jys0224!

    It seems that was the problem.


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