qt-everywhere-src-5.14.1/qtbase/examples/widgets/doc/src/twowaybutton.qdoc

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/*!
    \example statemachine/twowaybutton
    \title Two-way Button Example

    \brief The Two-way button example shows how to use \l{The State Machine
    Framework} to implement a simple state machine that toggles the current
    state when a button is clicked.

    \snippet statemachine/twowaybutton/main.cpp 0

    The application's main() function begins by constructing the application
    object, a button and a state machine.

    \snippet statemachine/twowaybutton/main.cpp 1

    The state machine has two states; \c on and \c off. When either state is
    entered, the text of the button will be set accordingly.

    \snippet statemachine/twowaybutton/main.cpp 2

    When the state machine is in the \c off state and the button is clicked,
    it will transition to the \c on state; when the state machine is in the \c
    on state and the button is clicked, it will transition to the \c off
    state.

    \snippet statemachine/twowaybutton/main.cpp 3

    The states are added to the state machine; they become top-level (sibling)
    states.

    \snippet statemachine/twowaybutton/main.cpp 4

    The initial state is \c off; this is the state the state machine will
    immediately transition to once the state machine is started.

    \snippet statemachine/twowaybutton/main.cpp 5

    Finally, the button is resized and made visible, and the application event
    loop is entered.

*/