qt5base-lts/examples/widgets/doc/eventtransitions.qdoc

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/*!
    \example statemachine/eventtransitions
    \title Event Transitions Example

    The Event Transitions example shows how to use event transitions, a
    feature of \l{The State Machine Framework}.

    \snippet statemachine/eventtransitions/main.cpp 0

    The \c Window class's constructors begins by creating a button.

    \snippet statemachine/eventtransitions/main.cpp 1

    Two states, \c s1 and \c s2, are created; upon entry they will assign
    "Outside" and "Inside" to the button's text, respectively.

    \snippet statemachine/eventtransitions/main.cpp 2

    When the button receives an event of type QEvent::Enter and the state
    machine is in state \c s1, the machine will transition to state \c s2.

    \snippet statemachine/eventtransitions/main.cpp 3

    When the button receives an event of type QEvent::Leave and the state
    machine is in state \c s2, the machine will transition back to state \c
    s1.

    \snippet statemachine/eventtransitions/main.cpp 4

    Next, the state \c s3 is created. \c s3 will be entered when the button
    receives an event of type QEvent::MouseButtonPress and the state machine
    is in state \c s2. When the button receives an event of type
    QEvent::MouseButtonRelease and the state machine is in state \c s3, the
    machine will transition back to state \c s2.

    \snippet statemachine/eventtransitions/main.cpp 5

    Finally, the states are added to the machine as top-level states, the
    initial state is set to be \c s1 ("Outside"), and the machine is started.

    \snippet statemachine/eventtransitions/main.cpp 6

    The main() function constructs a Window object and shows it.

*/