Struct IfMarker 

pub struct IfMarker {
    pub signal_name: String,
    pub body: Vec<Element>,
    pub currently_mounted: bool,
    pub mode: IfMode,
    pub eq: Option<String>,
    pub applied_visible: Option<bool>,
}

Marker for an <if signal="..."> block. The reconciler mounts / dismounts the subtree based on the named signal’s truthiness, or - when Self::eq is Some- on value equality.

A hidden IfMode::Hide block holds display: none in StyleOverrides (spec section 17.4: space is released and the relayout comes free via Changed<Style>), and lets go when it shows, so it shows with the display its styles give it then.

Fields

signal_name: String

Signal name to evaluate.

body: Vec<Element>

Markup children kept around as the body template - spawned when truthy, despawned when not.

currently_mounted: bool

Last-known mount state so we can detect transitions cheaply.

mode: IfMode

How to handle the transition (despawn vs hide).

eq: Option<String>

When Some(expected), mounts only when Signals[signal_name] == expected. When None, mounts when Signals[signal_name] is non-empty and not literal "false"/"0".

applied_visible: Option<bool>

IfMode::Hide only: the visibility state last applied to the entity (None = never applied). The reconciler only touches Style / Visible on a transition - re-inserting every tick kept FrameDirty permanently set (D5).

Trait Implementations

impl Clone for IfMarker

fn clone(&self) -> IfMarker

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Component for IfMarker

where IfMarker: Send + Sync + 'static,

Required Components: [lumen_core :: style_overrides :: StyleOverrides].

A component’s Required Components are inserted whenever it is inserted. Note that this will also insert the required components of the required components, recursively, in depth-first order.

const STORAGE_TYPE: StorageType = bevy_ecs::component::StorageType::Table

A constant indicating the storage type used for this component.

type Mutability = Mutable

A marker type to assist Bevy with determining if this component is mutable, or immutable. Mutable components will have [Component<Mutability = Mutable>], while immutable components will instead have [Component<Mutability = Immutable>].

fn register_required_components( _requiree: ComponentId, required_components: &mut RequiredComponentsRegistrator<'_, '_>, )

Registers required components.

fn clone_behavior() -> ComponentCloneBehavior

Called when registering this component, allowing to override clone function (or disable cloning altogether) for this component.

fn relationship_accessor() -> Option<ComponentRelationshipAccessor<IfMarker>>

Returns [ComponentRelationshipAccessor] required for working with relationships in dynamic contexts.

fn on_add() -> Option<for<'w> fn(DeferredWorld<'w>, HookContext)>

Gets the on_add [ComponentHook] for this [Component] if one is defined.

fn on_insert() -> Option<for<'w> fn(DeferredWorld<'w>, HookContext)>

Gets the on_insert [ComponentHook] for this [Component] if one is defined.

fn on_discard() -> Option<for<'w> fn(DeferredWorld<'w>, HookContext)>

Gets the on_discard [ComponentHook] for this [Component] if one is defined.

fn on_remove() -> Option<for<'w> fn(DeferredWorld<'w>, HookContext)>

Gets the on_remove [ComponentHook] for this [Component] if one is defined.

fn on_despawn() -> Option<for<'w> fn(DeferredWorld<'w>, HookContext)>

Gets the on_despawn [ComponentHook] for this [Component] if one is defined.

fn map_entities<E>(_this: &mut Self, _mapper: &mut E)

where E: EntityMapper,

Maps the entities on this component using the given [EntityMapper]. This is used to remap entities in contexts like scenes and entity cloning. When deriving [Component], this is populated by annotating fields containing entities with #[entities]

impl Debug for IfMarker

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

Formats the value using the given formatter.

impl StyleOwner for IfMarker

const RANK: u8 = 20

Where the owner’s values sit: a higher rank lays over a lower one.