EntitySpawnListener mixin

Hears every entity spawning and despawning, anywhere in the game.

The broad counterpart to EntityLifecycleListener. Mixed into a GameListener - typically a GameSystem - and collected by GameState's composition walk, so it hears the whole world:

class SpatialIndexSystem extends GameSystem with EntitySpawnListener {
  @override
  void onEntitySpawned(Entity entity) {
    if (entity.tryGet<Collider2D>() != null) index.insert(entity);
  }
}

Filtering by archetype is expected here, not a smell: a listener at this scope asked to see everything. Use EntityLifecycleListener instead when a struct only cares about its own entities - that one needs no filter.

Superclass constraints

Properties

hashCode → int
The hash code for this object.
no setterinherited
listensToEvents → bool
Whether this listener should receive events right now.
no setterinherited
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited

Methods

disableAfterUncaught() → void
Stops this listener receiving events, after it threw out of one.
inherited
noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
onEntityDespawned(Entity entity) → void
entity is going away. Its row is still readable here and never again afterwards.
onEntitySpawned(Entity entity) → void
entity has been created, with its field defaults already stamped into the row. Fired from the same call site as EntityLifecycleListener.onEntityMounted, so the two cannot disagree about when a spawn happened.
toString() → String
A string representation of this object.
inherited

Operators

operator ==(Object other) → bool
The equality operator.
inherited