Struct State 

pub struct State<S>(/* private fields */)
where
    S: States;

A finite-state machine whose transitions have associated schedules (OnEnter(state) and OnExit(state)).

The current state value can be accessed through this resource. To change the state, queue a transition in the NextState<S> resource, and it will be applied during the StateTransition schedule - which by default runs after PreUpdate.

You can also manually trigger the StateTransition schedule to apply the changes at an arbitrary time.

The starting state is defined via the Default implementation for S.

use bevy_state::prelude::*;
use bevy_ecs::prelude::*;
use bevy_state_macros::States;

#[derive(Clone, Copy, PartialEq, Eq, Hash, Debug, Default, States)]
enum GameState {
    #[default]
    MainMenu,
    SettingsMenu,
    InGame,
}

fn game_logic(game_state: Res<State<GameState>>) {
    match game_state.get() {
        GameState::InGame => {
            // Run game logic here...
        },
        _ => {},
    }
}

Implementations

impl<S> State<S>

where S: States,

pub fn new(state: S) -> State<S>

Creates a new state with a specific value.

To change the state use NextState<S> rather than using this to modify the State<S>.

pub fn get(&self) -> &S

Get the current state.

Trait Implementations

impl<S> Debug for State<S>

where S: Debug + States,

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl<S> Deref for State<S>

where S: States,

type Target = S

The resulting type after dereferencing.

fn deref(&self) -> &<State<S> as Deref>::Target

Dereferences the value.

impl<S> FromReflect for State<S>

where S: States + TypePath + FromReflect + MaybeTyped + RegisterForReflection, State<S>: Any + Send + Sync,

fn from_reflect(reflect: &(dyn PartialReflect + 'static)) -> Option<State<S>>

Constructs a concrete instance of Self from a reflected value.

fn take_from_reflect( reflect: Box<dyn PartialReflect>, ) -> Result<Self, Box<dyn PartialReflect>>

Attempts to downcast the given value to Self using, constructing the value using from_reflect if that fails.

impl<S> FromWorld for State<S>

where S: States + FromWorld,

fn from_world(world: &mut World) -> State<S>

Creates Self using data from the given World.

impl<S> GetTypeRegistration for State<S>

where S: States + TypePath + FromReflect + MaybeTyped + RegisterForReflection, State<S>: Any + Send + Sync,

fn get_type_registration() -> TypeRegistration

Returns the default TypeRegistration for this type.

fn register_type_dependencies(registry: &mut TypeRegistry)

Registers other types needed by this type.

impl<S> PartialEq<S> for State<S>

where S: States,

fn eq(&self, other: &S) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<S> PartialReflect for State<S>

where S: States + TypePath + FromReflect + MaybeTyped + RegisterForReflection, State<S>: Any + Send + Sync,

fn get_represented_type_info(&self) -> Option<&'static TypeInfo>

Returns the TypeInfo of the type represented by this value.

fn try_apply( &mut self, value: &(dyn PartialReflect + 'static), ) -> Result<(), ApplyError>

Tries to apply a reflected value to this value.

fn reflect_kind(&self) -> ReflectKind

Returns a zero-sized enumeration of “kinds” of type.

fn reflect_ref(&self) -> ReflectRef<'_>

Returns an immutable enumeration of “kinds” of type.

fn reflect_mut(&mut self) -> ReflectMut<'_>

Returns a mutable enumeration of “kinds” of type.

fn reflect_owned(self: Box<State<S>>) -> ReflectOwned

Returns an owned enumeration of “kinds” of type.

fn try_into_reflect( self: Box<State<S>>, ) -> Result<Box<dyn Reflect>, Box<dyn PartialReflect>>

Attempts to cast this type to a boxed, fully-reflected value.

fn try_as_reflect(&self) -> Option<&(dyn Reflect + 'static)>

Attempts to cast this type to a fully-reflected value.

fn try_as_reflect_mut(&mut self) -> Option<&mut (dyn Reflect + 'static)>

Attempts to cast this type to a mutable, fully-reflected value.

fn into_partial_reflect(self: Box<State<S>>) -> Box<dyn PartialReflect>

Casts this type to a boxed, reflected value.

fn as_partial_reflect(&self) -> &(dyn PartialReflect + 'static)

Casts this type to a reflected value.

fn as_partial_reflect_mut(&mut self) -> &mut (dyn PartialReflect + 'static)

Casts this type to a mutable, reflected value.

fn reflect_partial_eq( &self, value: &(dyn PartialReflect + 'static), ) -> Option<bool>

Returns a “partial equality” comparison result.

fn debug(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Debug formatter for the value.

fn reflect_clone(&self) -> Result<Box<dyn Reflect>, ReflectCloneError>

Attempts to clone Self using reflection.

fn apply(&mut self, value: &(dyn PartialReflect + 'static))

Applies a reflected value to this value.

fn clone_value(&self) -> Box<dyn PartialReflect>

👎Deprecated since 0.16.0: to clone reflected values, prefer using reflect_clone. To convert reflected values to dynamic ones, use to_dynamic.

Clones Self into its dynamic representation.

fn to_dynamic(&self) -> Box<dyn PartialReflect>

Converts this reflected value into its dynamic representation based on its kind.

fn reflect_hash(&self) -> Option<u64>

Returns a hash of the value (which includes the type).

fn is_dynamic(&self) -> bool

Indicates whether or not this type is a dynamic type.

impl<S> Reflect for State<S>

where S: States + TypePath + FromReflect + MaybeTyped + RegisterForReflection, State<S>: Any + Send + Sync,

fn into_any(self: Box<State<S>>) -> Box<dyn Any>

Returns the value as a Box<dyn Any>.

fn as_any(&self) -> &(dyn Any + 'static)

Returns the value as a &dyn Any.

fn as_any_mut(&mut self) -> &mut (dyn Any + 'static)

Returns the value as a &mut dyn Any.

fn into_reflect(self: Box<State<S>>) -> Box<dyn Reflect>

Casts this type to a boxed, fully-reflected value.

fn as_reflect(&self) -> &(dyn Reflect + 'static)

Casts this type to a fully-reflected value.

fn as_reflect_mut(&mut self) -> &mut (dyn Reflect + 'static)

Casts this type to a mutable, fully-reflected value.

fn set(&mut self, value: Box<dyn Reflect>) -> Result<(), Box<dyn Reflect>>

Performs a type-checked assignment of a reflected value to this value.

impl<S> TupleStruct for State<S>

where S: States + TypePath + FromReflect + MaybeTyped + RegisterForReflection, State<S>: Any + Send + Sync,

fn field(&self, index: usize) -> Option<&(dyn PartialReflect + 'static)>

Returns a reference to the value of the field with index index as a &dyn Reflect.

fn field_mut( &mut self, index: usize, ) -> Option<&mut (dyn PartialReflect + 'static)>

Returns a mutable reference to the value of the field with index index as a &mut dyn Reflect.

fn field_len(&self) -> usize

Returns the number of fields in the tuple struct.

fn iter_fields(&self) -> TupleStructFieldIter<'_>

Returns an iterator over the values of the tuple struct’s fields.

fn to_dynamic_tuple_struct(&self) -> DynamicTupleStruct

Creates a new DynamicTupleStruct from this tuple struct.

fn clone_dynamic(&self) -> DynamicTupleStruct

👎Deprecated since 0.16.0: use to_dynamic_tuple_struct instead

Clones the struct into a DynamicTupleStruct.

fn get_represented_tuple_struct_info(&self) -> Option<&'static TupleStructInfo>

Will return None if TypeInfo is not available.

impl<S> TypePath for State<S>

where S: States + TypePath, State<S>: Any + Send + Sync,

fn type_path() -> &'static str

Returns the fully qualified path of the underlying type.

fn short_type_path() -> &'static str

Returns a short, pretty-print enabled path to the type.

fn type_ident() -> Option<&'static str>

Returns the name of the type, or None if it is anonymous.

fn crate_name() -> Option<&'static str>

Returns the name of the crate the type is in, or None if it is anonymous.

fn module_path() -> Option<&'static str>

Returns the path to the module the type is in, or None if it is anonymous.

impl<S> Typed for State<S>

where S: States + TypePath + FromReflect + MaybeTyped + RegisterForReflection, State<S>: Any + Send + Sync,

fn type_info() -> &'static TypeInfo

Returns the compile-time info for the underlying type.

impl<S> Resource for State<S>

where S: States, State<S>: Send + Sync + 'static,