StateSystem

My version of a finite state machine for Unity.

(Note: all the classes in this repository that would inherit from MonoBehaviour inherit from ManagedBehaviour instead, an abstract class that I use to better manage what should be executing and when).

• State: a ScriptableObject that, along with the StateMachine component, is the core of the system.

  • ID: returns a string that serves to identify the state.

• StateMachine: the core class of the system. It's a component containing an array of states that can be added through the inspector.

  • PreviousState: returns the previous state of the object.
  • CurrentState: returns the current state of the object.
  • Initialize (2 overloads): if the object has an event handler or one or more state behaviours, this makes them ready to work.
  • SubscribeToSetState (2 overloads): subscribes to an event that is fired when the specified state is set.
  • SubscribeToClearState (2 overloads): subscribes to an event that is fired when the specified state is cleared.
  • UnsubscribeFromSetState (2 overloads): unsubscribes from an event that is fired when the specified state is set.
  • UnsubscribeFromClearState (2 overloads): unsubscribes from an event that is fired when the specified state is cleared.
  • GetStates: returns an array with all the possible states of the object.
  • ContainsState (2 overloads): returns true if the specified state is among the ones in the object.
  • IsPreviousState (2 overloads): returns true if the specified state is the previous one.
  • IsCurrentState (2 overloads): returns true if the specified state is the current one.
  • SetState (2 overloads): sets the specified state as current.
  • SetPreviousState: sets the previous state as current.
  • ExecuteBehaviours: runs all the behaviours linked to the current state.

• StateBehaviour: an abstract class that requires a StateMachine component. Any class inheriting from this one should be linked to one or more states through the inspector.

  • Initialize: prepares the class to work.
  • GetLinkedStates: returns an array with all the states linked to this behaviour.
  • OnSetState: virtual method (empty by default) that is called automatically every time one of the linked states is set.
  • Execute: abstract method that contains the actual behaviour.
  • OnClearState: virtual method (empty by default) that is called automatically every time one of the linked states is cleared.

• StateBehaviourArgs: an optional abstract class that can be used to pass data to a state behaviour when initializing it.

  • Empty: returns an empty StateBehaviourArgs.

• StateEventHandler: an optional class that requires a StateMachine component. It's used to subscribe to, or unsubscribe from, the events of that machine without exposing its other methods and properties to the listener.

  • Initialize: prepares the class to work.
  • SubscribeToSetState (2 overloads): subscribes to an event that is fired when the specified state is set.
  • SubscribeToClearState (2 overloads): subscribes to an event that is fired when the specified state is cleared.
  • UnsubscribeFromSetState (2 overloads): unsubscribes from an event that is fired when the specified state is set.
  • UnsubscribeFromClearState (2 overloads): unsubscribes from an event that is fired when the specified state is cleared.