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var fsm;
var state;
var trans;
// Create a new finite state machine called "Test Machine"
fsm = new qx.util.finitestatemachine.Fsm("Test machine");
// State S1
state = new qx.util.finitestatemachine.State(
// State name
"S1",
// Object with state information
{
// Function called on entry to this state
"onentry" :
function(fsm, event)
{
alert("Previous state: " + fsm.getPreviousState());
};
// Function called on exit from this state
"onexit" :
function(fsm, event)
{
alert("Next state: " + fsm.getNextState());
};
// Automatic actions to take place before a (possibly) new state's onentry
// function is called.
"autoActionsBeforeOnentry" :
{
// The name of a function.
"setEnabled" :
[
{
// The parameter value(s), thus "setEnabled(true);"
"parameters" : [ true ],
// The function would be called on each object:
// this.getObject("obj1").setEnabled(true);
// this.getObject("obj2").setEnabled(true);
"objects" : [ "obj1", "obj2" ]
// And similarly for each object in each specified group.
"groups" : [ "group1", "group2" ],
}
];
"setColor" :
[
{
"parameters" : [ "blue" ]
"groups" : [ "group3", "group4" ],
"objects" : [ "obj3", "obj4" ]
}
];
};
// also available, in same format as actionsBeforeOnentry:
// "actionsAfterOnentry",
// "actionsBeforeOnexit"
// "actionsAfterOnexit"
// Events handled by this state, or queued for processing by a future state
"events" :
{
// The event type "compete" is handled by one of the transitions in this
// state. The transitions will be searched in order of their addition
// to the state, until the predicate for a transition returns true (or
// no predicate is specified for the transition, which is an implicit
// "true") That transition will be used.
"complete" : qx.util.finitestatemachine.Fsm.EventHandling.PREDICATE,
// The event type "interval" has two objects specified by their
// "friendly name". The action when an event of type "interval" occurs
// depends on which object was the target of the event.
"interval" :
{
// If the target of the event was the object to which we have given
// the friendly name "flash" then use a transition specified by name
"flash" : "S1_S3_interval_flash",
// If the target of the event was the object to which we have given
// the friendly name "timeout", then enqueue this event for possible
// processing by a future state.
"timeout" : qx.util.finitestatemachine.Fsm.EventHandling.BLOCKED
},
// The event type "execute", too, has two objects specified by their
// "friendly name".
"execute" :
{
// If the target of the event was the object to which we have given
// the friend name "ok", search the transitions in order looking for
// one where the predicate is true
"ok" : qx.util.finitestatemachine.Fsm.EventHandling.PREDICATE
// If the target of the event was the object to which we have given
// the friendly name "restart", then enqueue this event for possible
// processing by a future state.
"restart" : qx.util.finitestatemachine.Fsm.EventHandling.BLOCKED
}
// all events other than those which are handled or blocked are ignored.
};
});
// Add State S1 to the finite state machine.
fsm.addState(state);
// Transition from S1 to S2 due to event 1
trans = new qx.util.finitestatemachine.Transition(
// Transition name
"S1_S2_ev1",
// Object with transition information
{
// return TRUE to pass
"predicate" :
function(fsm, event)
{
var type = event.getType();
if (type == "somethingWeCareAbout")
{
return true;
}
else if (type == "somethingToHandleInAnotherState")
{
// reattempt event delivery following state transition
fsm.postponeEvent(event);
// do no further transition attempts for this event for now
return null;
}
else
{
return false;
}
},
// if event matches and predicate passes, pop the state stack and go to
// the state which was found at the top of the stack. States are added to
// the state stack by calling fsm.pushState() during a state's onexit
// function or by a transition's action function.
"nextState" : qx.util.finintestatemachine.Fsm.StateChange.POP_STATE_STACK,
// action taken during transisition
"action" :
function(fsm, event)
{
// save current state so a future transition can get back to
// this saved state
fsm.pushState();
}
});
state.addTransition(trans);
// Default transition (any event): remain in current state
trans = new qx.util.finitestatemachine.Transition(
"S1_S1_default",
{
// true or undefined : always pass
"predicate" :
function(fsm, event)
{
// This predicate does not pass, and we return null to tell the finite
// state machine that no additional transitions in the transition list
// should be tested. (Note that the next transition is the one
// explicitly called for by the "interval" event on the object with
// friendly name "flash". We do not want a predicate search to find
// it.
return null;
},
// return to current state
"nextState" : qx.util.finitestatemacine.CURRENT_STATE,
});
state.addTransition(trans);
// Transition from S1 to S2 due to event 2. Since the previous transition
// returned null in its predicate function, the only way to get to this
// transition is when it is called out explicitly in the state's event list.
// This one was specified for the "interval" event on the object with friendly
// name "flash".
trans = new qx.util.finitestatememachine.Transition(
"S1_S3_interval_flash",
{
// No predicate or a value of 'true' means that the predicate passes as if
// a predicate function returned true.
"predicate" : true,
// if event matches, go to this state
"nextState" : "S2",
// action taken during transisition
"action" :
function(fsm, event)
{
alert(this.getName() + "action function");
}
});
state.addTransition(trans);
// We would, of course, need to add state S2 since it is specified in a
// nextState property. That is left as an exercise for the reader.
// Initialize and start the machine running
fsm.start();
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