/// <summary>
/// Add a state transition to the FSM
/// </summary>
/// <param name="state">The state</param>
/// <param name="eventId">The transition event</param>
public void AddTransition(FSMStateId fromState, FSMEventId eventId, IState <TContext> state)
{
var transitionKey = new KeyValuePair <FSMStateId, FSMEventId>(fromState, eventId);
Debug.Assert(!transitions.ContainsKey(transitionKey), string.Format("Overwriting gesture {0}", eventId.ToString()));
state.Controller = this;
this.transitions[transitionKey] = state;
}
/// <summary>
/// Performs a state transition for a gesture
/// </summary>
/// <param name="eventId">The gesture for which to change state</param>
public virtual void PerformTransition(FSMEventId eventId)
{
FSMStateId oldStateId = this.currentState != null ? this.currentState.Id : FSMStateId.Unknown;
var transitionKey = this.GetTransitionKey(eventId);
IState <TContext> oldState = this.currentState;
if (!transitions.ContainsKey(transitionKey))
{
throw new ApplicationException(string.Format("No transition for event {0} found", eventId.ToString()));
}
currentState = transitions[transitionKey];
if (currentState == null)
{
throw new ApplicationException(string.Format("Invalid state for event {0}", eventId.ToString()));
}
// we only enter/exit states if anything really changed
if (currentState.Id != transitionKey.Key)
{
if (oldState != null)
{
oldState.StateExited();
}
currentState.StateEntered(this.sharedContext);
if (this.StateChanged != null)
{
this.StateChanged(this, new StateChangedEventArgs()
{
OldState = oldStateId, NewState = currentState.Id
});
}
}
}
/// <summary>
/// Loads the gesture to eventid mapping
/// </summary>
/// <param name="config">The configuration node</param>
private void LoadGestureTransitions(XmlDocument config)
{
config.ProcessXmlNodes("//configuration/gesturetransitions/gesturetransition",
transition =>
{
FSMStateId fromStateId = (FSMStateId)int.Parse(transition.Attributes["fromState"].Value);
GestureId gestureId = (GestureId)int.Parse(transition.Attributes["onGesture"].Value);
FSMEventId eventId = (FSMEventId)int.Parse(transition.Attributes["raiseStateEvent"].Value);
if (!this.Gestures.ContainsKey(gestureId))
{
throw new InvalidDataException(string.Format("Gesture {0} is not specified in the gestures section of the config file",
gestureId.ToString()));
}
if (!this.States.ContainsKey(fromStateId))
{
throw new InvalidDataException(string.Format("State {0} is not specified in the states section of the config file",
fromStateId.ToString()));
}
this.GestureTransitions[new KeyValuePair <FSMStateId, GestureId>(fromStateId, gestureId)] = eventId;
});
}
/// <summary>
/// Loads the states transitions
/// </summary>
/// <param name="config">The configuration node</param>
private void LoadStateTransitions(XmlDocument config)
{
config.ProcessXmlNodes("//configuration/statetransitions/transition",
transition =>
{
FSMStateId fromStateId = (FSMStateId)int.Parse(transition.Attributes["fromState"].Value);
FSMStateId toStateId = (FSMStateId)int.Parse(transition.Attributes["moveToState"].Value);
FSMEventId eventId = (FSMEventId)int.Parse(transition.Attributes["onEvent"].Value);
if (!this.States.ContainsKey(fromStateId) && fromStateId != FSMStateId.Unknown)
{
throw new InvalidDataException(string.Format("State {0} is not specified in the states section of the config file",
fromStateId.ToString()));
}
if (!this.States.ContainsKey(toStateId))
{
throw new InvalidDataException(string.Format("State {0} is not specified in the states section of the config file",
toStateId.ToString()));
}
this.StateTransitions[new KeyValuePair <FSMStateId, FSMEventId>(fromStateId, eventId)] = toStateId;
});
}
/// <summary>
/// Returns a key that can be used for identifying transitions in the FSM
/// </summary>
/// <param name="eventId">The event id</param>
/// <returns>A transition key</returns>
private KeyValuePair <FSMStateId, FSMEventId> GetTransitionKey(FSMEventId eventId)
{
return(new KeyValuePair <FSMStateId, FSMEventId>(this.currentState == null ? FSMStateId.Unknown : this.currentState.Id, eventId));
}
public GestureRecognizedEventArgs(IGesture gesture, FSMEventId eventId)
{
this.Gesture = gesture;
this.Event = eventId;
}
