/// <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>
/// 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;
}