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/*!
    \example animation/animatedtiles
    \title Animated Tiles Example
    \ingroup examples-qtstatemachine

    \brief The Animated Tiles example animates items in a graphics scene.

    The example demonstrates how QStateMachine states can be used to animate
    positions of graphical objects. There are five states in the application that
    can be triggered by five buttons. The buttons initiate state transitions
    that animate the positions of 64 QGraphicsPixmapItem images.

    \image animatedtiles-example.png

    \section1 The \c main() Function

    \snippet animation/animatedtiles/main.cpp 0

    The QGraphicsScene is created, then the 64 images are created and added to the scene
    with the initial position of the center of the window.
    The Pixmap class is defined in the example that extends the QGraphicsPixmapItem so that
    its position can be read and written as Qt properties.

    \snippet animation/animatedtiles/main.cpp 1

    Then the five buttons are created and added to a QGraphicsItem for easier positioning.
    The Button class is defined in the example. It extends QGraphicsWidget and implements
    displaying a QPixmap on a circular background with shading based on its pressed state.

    \snippet animation/animatedtiles/main.cpp 2

    The states are created and added to a root state.

    \image animated-tiles-chart.png

    Having the five states as child states of \c rootState allows state transitions from any
    of the child states to any other child state if the state transitions are set up from
    \c rootState to the child states.

    \snippet animation/animatedtiles/main.cpp 3

    For each image, the position properties are set to each state based on a function that
    creates the required shape. The states set these properties to the images when the
    given state is entered.

    \snippet animation/animatedtiles/main.cpp 4

    The QGraphicsView is created and set up with the required properties.

    \snippet animation/animatedtiles/main.cpp 5

    The state machine is created and the previously created states are added with the \c rootState
    set as the initial state.

    \snippet animation/animatedtiles/main.cpp 6

    The QParallelAnimationGroup is created with a QPropertyAnimation for each item that animates
    the item position values.

    \snippet animation/animatedtiles/main.cpp 7

    The state transitions are created with the button presses as their triggers and the animation
    group assigned to them.

    \snippet animation/animatedtiles/main.cpp 8

    An initial state transition is set up from root to ellipse state that is triggered with a
    QTimer after application start.
*/