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| /*! |
| \example statemachine/pingpong |
| \title Ping Pong States Example |
| |
| \brief The Ping Pong States example shows how to use parallel states together |
| with custom events and transitions in \l{The State Machine Framework}. |
| |
| This example implements a statechart where two states communicate by |
| posting events to the state machine. The state chart looks as follows: |
| |
| \image pingpong-example.png |
| \omit |
| \caption This is a caption |
| \endomit |
| |
| The \c pinger and \c ponger states are parallel states, i.e. they are |
| entered simultaneously and will take transitions independently of |
| eachother. |
| |
| The \c pinger state will post the first \c ping event upon entry; the \c |
| ponger state will respond by posting a \c pong event; this will cause the |
| \c pinger state to post a new \c ping event; and so on. |
| |
| \snippet statemachine/pingpong/main.cpp 0 |
| |
| Two custom events are defined, \c PingEvent and \c PongEvent. |
| |
| \snippet statemachine/pingpong/main.cpp 1 |
| |
| The \c Pinger class defines a state that posts a \c PingEvent to the state |
| machine when the state is entered. |
| |
| \snippet statemachine/pingpong/main.cpp 2 |
| |
| The \c PingTransition class defines a transition that is triggered by |
| events of type \c PingEvent, and that posts a \c PongEvent (with a delay |
| of 500 milliseconds) to the state machine when the transition is |
| triggered. |
| |
| \snippet statemachine/pingpong/main.cpp 3 |
| |
| The \c PongTransition class defines a transition that is triggered by |
| events of type \c PongEvent, and that posts a \c PingEvent (with a delay |
| of 500 milliseconds) to the state machine when the transition is |
| triggered. |
| |
| \snippet statemachine/pingpong/main.cpp 4 |
| |
| The main() function begins by creating a state machine and a parallel |
| state group. |
| |
| \snippet statemachine/pingpong/main.cpp 5 |
| |
| Next, the \c pinger and \c ponger states are created, with the parallel |
| state group as their parent state. Note that the transitions are \e |
| targetless. When such a transition is triggered, the source state won't be |
| exited and re-entered; only the transition's onTransition() function will |
| be called, and the state machine's configuration will remain the same, |
| which is precisely what we want in this case. |
| |
| \snippet statemachine/pingpong/main.cpp 6 |
| |
| Finally, the group is added to the state machine, the machine is started, |
| and the application event loop is entered. |
| |
| */ |