StateMachine

StateMachine is a finite/hierarchical state machine framework written in Objective-C for iOS. The framework can be used to implement UML state diagrams.

The documentation/examples is currently insufficient - sorry. I have plans to make a demo where some button on the UI can be used to generate events.

References

• Wikipedia

Features

The framework is developed based on my needs and currently I have identified the following supported and unsupported features:

Supported

• Events
• States
• Extended states (state variables)
• Transitions
  • Regular
  • Default
  • Initial
  • Internal
  • Self
• Actions
  • Entry
  • Exit
  • Transition
• Guards
• After (timeout)

Unsupported

• Orthogonal regions
• External transitions
• Deferred events
• Deep history
• Shallow history

Traces

The framework has iOS traces that are written to the Xcode Target Output. Example:

 Starting machine: Machine
   Initial transition started:  • -> MyStateA
     MyStateA entered
 MyStateA entryAction
   Initial transition completed
 Machine started
 EventWithoutData with object (null) catched by MyStateA
   Transition started: MyStateA -> MyStateB
 MyStateA exitAction
     MyStateA exited
     MyStateB entered
   Default transition: MyStateB -> MyStateB1
     MyStateB1 entered
   Transition completed
 EventWithNumber: with object 5 catched by MyStateB1
 EventWithDictionary: with object { key = 4; } catched by MyStateB1

Notes

The state hierarchy is solved lazily at run-time.

History

The framework is based on a C-version I made in April 2005.