states 0.9.1

States is Finite State Machine for Dart. You can define states of your application and reaction on transition between states

States - Finite State Machine for Dart v0.1.0

A library for Dart developers.

IStates {
	
	/**
	 * What is the current state?
	 * @return The current state.
	 */
	String current();
	
	/**
	 * Does an action or a state exist in the state machine?
	 * @param action The action in question.
	 * @param state The state in question.
	 * @param conform The state in question.
	 * @return True if the action or state exists, false if it does not.
	 */
	bool has({ String action, String state });
	
	/**
	 * Add a valid link between two states.
	 * The state machine can then move between
	 * @param fromState State you want to move from.
	 * @param toState State you want to move to.
	 * @param action Action that when performed will move from the from state to the to state.
	 * @param handler Optional method that gets called when moving between these two states.
	 * @return true if link was added, false if it was not.
	 */
	bool action( String fromState, String toState, String action, [ Function handler = null ]);
	
	/**
	 * Adds a new state to the state machine.
	 * @param newState The new state to add.
	 * @return True is teh state was added, false if it was not.
	 */
	bool add( String newState );
	
	/**
	 * Move from the current state to another state.
	 * @param toState New state to try and move to.
	 * @return True if the state machine has moved to this new state, false if it was unable to do so.
	 */
	bool change( String toState );
	
	/**
	 * Change the current state by performing an action.
	 * @param action The action to perform.
	 * @return True if the action was able to be performed and the state machine moved to a new state, false if the action was unable to be performed.
	 */
	bool perform( String actionName );
	
	/**
	 * What are the valid actions you can perform from the current state?
	 * @return An array of actions.
	 */
	List<Action> actions();
	
	/**
	 * What are the valid states you can get to from the current state?
	 * @return An array of states.
	 */
	List<Meta> metas();
	
	/**
	 * Go back to the initial starting state
	 */
	void reset();
}

Usage

A simple usage example:

States states = new States();

   states.add( STATE_INITIAL );

   states.add( STATE_LOADING );
   states.add( STATE_LOADING_COMPLETE );
   states.add( STATE_LOADING_FAILED );

   states.add( STATE_PREPARE_MODEL );
   states.add( STATE_PREPARE_CONTROLLER );
   states.add( STATE_PREPARE_VIEW );
   states.add( STATE_PREPARE_COMPLETE );
   states.add( STATE_READY );

   states.action(
           STATE_INITIAL,
           STATE_LOADING,
           ACTION_LOADING_START,
           () {
               print("> CURRENT on ACTION_LOADING_START state: " + states.current());
               scheduleMicrotask(() {
                   print("> \t END OF microtask queue -> state: " + states.current());
                   var nextBool = Random.secure().nextBool();
                   print("> \t\t next bool: " + nextBool.toString());
                   states.perform(
                           nextBool ?
                           ACTION_LOADING_COMPLETE :
                           ACTION_LOADING_FAILED
                   );
               });
           });

   states.action(
           STATE_LOADING,
           STATE_LOADING_COMPLETE,
           ACTION_LOADING_COMPLETE,
           () {
               print("> CURRENT on ACTION_LOADING_COMPLETE - state: " + states.current());
               scheduleMicrotask(() => print("> \t END OF microtask queue -> state: " + states.current()));
           }
   );

   states.action(
           STATE_LOADING,
           STATE_LOADING_FAILED,
           ACTION_LOADING_FAILED,
           () {
               print("> CURRENT on ACTION_LOADING_FAILED state: " + states.current());
               scheduleMicrotask(() => print("> \t END OF microtask queue -> state: " + states.current()));
           }
   );

   states.perform( ACTION_LOADING_START );

Features and bugs