Usage¶

StateDiagram allows the creation of state diagrams.

StateDiagram Objects¶

States¶

Note

StateDiagram documentation differentiates between state and State

state is an implementation of StateInterface and may be the source and/or destination of a transition.

State is a particular implementation of StateInterface that represents a system state and may contain States, Choices, Forks, Joins, and Groups.

The types of states are:

State - State represent a particular state of a system.
A State may contain States, Choices, Forks, and Joins; such a State is a Composite States. Composite states can be nested to any depth. States may also contain Groups and/or have a Note attached.
Choice - Choice states represent a choice, allowing the transition path to be dependent on a value.
Fork - Fork states represent a fork, allowing two or more paths to be followed.
Join - Join states represent a join of multiple paths into a single path.

Groups¶

Groups may be added to States. Groups contain nodes and transitions. Groups within a State indicate concurrency.

Notes¶

Notes can be added to States. A Note provides additional information about the State it is added to.

Transitions¶

Transitions are paths/edges from one state to another. Transitions can be labelled to describe the transition.

Example¶

PHP¶

$fork = new Fork('fork_state');
$join = new Join('join_state');
$choice = new Choice('if_state');
$state1 = new State('State1');
$state2 = new State('State2');
$state3 = new State('State3');
$state4 = new State('State4');
$isPositive = new State('IsPositive', 'Is Positive');
$false = new State('False');
$true = new State('True');
$first = (new State('First))
    ->withState($fir = new State('fir'))
    ->withTransition(null, $fir)
    ->withTransition($fir)
;
$second = (new State('Second'))
    ->withState($sec = new State('sec'))
    ->withTransition(null, $sec)
    ->withTransition($sec)
;
$third = (new State('Third'))
    ->withState($thi = new State('thi'))
    ->withTransition(null, $thi)
    ->withTransition($thi)
;
$active = (new State('Active))
    ->withGroup(
        (new Group())
            ->withState(
                $capsLockOff = new State(CapsLockOff),
                $capsLockOn = new State(CapsLockOn)
            )
            ->withTransition(
                new Transition(null, $capsLockOff),
                new Transition($capsLockOff, $capsLockOn),
                new Transition($capsLockOn, $capsLockOff)
            )
        ,
        (new Group())
            ->withState(
                $numLockOff = State(NumLockOff),
                $numLockOn = new State(NumLockOn)
            )
            ->withTransition(
                new Transition(null, $numLockOff),
                new Transition($numLockOff, $numLockOn),
                new Transition($numLockOn, $numLockOff)
            )
        ,
        (new Group())
            ->withState(
                $scrollLockOff = new State(ScrollLockOff),
                $scrollLockOn = new State(ScrollLockOn)
            )
            ->withTransition(
                new Transition(null, $scrollLockOff),
                new Transition($scrollLockOff, $scrollLockOn),
                new Transition($scrollLockOn, $scrollLockOff)
            )
        ,
    )
;

echo Mermaid::create(StateDiagram::class)
    ->withDirection(Direction::leftRight)
    ->withState(
        $fork,
        $join,
        $choice,
        $state1,
        $state2,
        $state3,
        $state4,
        $false,
        $true,
        $active
    )
    withTransition(
        new Transition(null, $fork),
        new Transition($fork, $state1),
        new Transition($fork, $state2),
        new Transition($state1, $join),
        new Transition($state2, $join),
        new Transition($join, $state4),
        new Transition($state4, $isPositive),
        new Transition($isPositive, $choice),
        new Transition($choice, $false, 'if n < 0'),
        new Transition($choice, $true, 'if n >= 0'),
        new Transition($false, $active),
        new Transition($tree, $first),
        new Transition($first, $second),
        new Transition($first, $third),
    )
    ->render()
;

Generated Mermaid¶

<pre class="mermaid">
stateDiagram-v2
  direction LR
  state fork_state <<fork>>
  state join_state <<join>>
  state if_state <<choice>>
  state "State1" as State1
  state "State2" as State2
  state "State3" as State3
  state "State4" as State4
  state "False" as False
  state "True" as True
  state "Active" as Active {
    state "CapsLockOff" as CapsLockOff
    state "CapsLockOn" as CapsLockOn
    [*] --> CapsLockOff
    CapsLockOff --> CapsLockOn : EvCapsLockPressed
    CapsLockOn --> CapsLockOff : EvCapsLockPressed
    --
    state "NumLockOff" as NumLockOff
    state "NumLockOn" as NumLockOn
    [*] --> NumLockOff
    NumLockOff --> NumLockOn : EvNumLockPressed
    NumLockOn --> NumLockOff : EvNumLockPressed
    --
    state "ScrollLockOff" as ScrollLockOff
    state "ScrollLockOn" as ScrollLockOn
    [*] --> ScrollLockOff
    ScrollLockOff --> ScrollLockOn : EvScrollLockPressed
    ScrollLockOn --> ScrollLockOff : EvScrollLockPressed
  }
  state "First" as First {
    state "fir" as fir
    [*] --> fir
    fir --> [*]
  }
  state "Second" as Second {
    state "sec" as sec
    [*] --> sec
    sec --> [*]
  }
  state "Third" as Third {
    state "thi" as thi
    [*] --> thi
    thi --> [*]
  }
  [*] --> fork_state
  fork_state --> State1
  fork_state --> State2
  State1 --> join_state
  State2 --> join_state
  join_state --> State4
  State4 --> IsPositive
  IsPositive --> if_state
  if_state --> False : if n < 0
  if_state --> True : if n >= 0
  False --> Active
  True --> First
  First --> Second
  First --> Third
</pre>

Mermaid Diagram¶

        stateDiagram-v2
  direction LR
  state fork_state <<fork>>
  state join_state <<join>>
  state if_state <<choice>>
  state "State1" as State1
  state "State2" as State2
  state "State3" as State3
  state "State4" as State4
  state "False" as False
  state "True" as True
  state "Active" as Active {
    state "CapsLockOff" as CapsLockOff
    state "CapsLockOn" as CapsLockOn
    [*] --> CapsLockOff
    CapsLockOff --> CapsLockOn : EvCapsLockPressed
    CapsLockOn --> CapsLockOff : EvCapsLockPressed
    --
    state "NumLockOff" as NumLockOff
    state "NumLockOn" as NumLockOn
    [*] --> NumLockOff
    NumLockOff --> NumLockOn : EvNumLockPressed
    NumLockOn --> NumLockOff : EvNumLockPressed
    --
    state "ScrollLockOff" as ScrollLockOff
    state "ScrollLockOn" as ScrollLockOn
    [*] --> ScrollLockOff
    ScrollLockOff --> ScrollLockOn : EvScrollLockPressed
    ScrollLockOn --> ScrollLockOff : EvScrollLockPressed
  }
  state "First" as First {
    state "fir" as fir
    [*] --> fir
    fir --> [*]
  }
  state "Second" as Second {
    state "sec" as sec
    [*] --> sec
    sec --> [*]
  }
  state "Third" as Third {
    state "thi" as thi
    [*] --> thi
    thi --> [*]
  }
  [*] --> fork_state
  fork_state --> State1
  fork_state --> State2
  State1 --> join_state
  State2 --> join_state
  join_state --> State4
  State4 --> IsPositive
  IsPositive --> if_state
  if_state --> False : if n < 0
  if_state --> True : if n >= 0
  False --> Active
  True --> First
  First --> Second
  First --> Third