Component class abstract base

Base class for all Pulsar components.

A Component is a long-lived object with identity — it is never recreated on re-render. Instead, it morphs its output in-place when state changes via morph.

Lifecycle

  1. Instantiate the component and store it as a field (never inline).
  2. The runtime calls attach once when the component is mounted.
  3. State changes are driven by morph, which runs an updater function and triggers a granular DOM reconciliation scoped to this component.
  4. detach is called when the component is removed from the tree.

Rules

  • render must be pure: no side effects, no lazy iteration inside it. Compute derived data in getters and reference those getters from render.
  • Components must be stored as fields, not created inline, so that identity and state are preserved across re-renders.

Example

final class Counter extends Component {
  int count = 0;

  void increment(Event _) => morph(() => count++);
  void decrement(Event _) => morph(() => count--);

  @override
  Morphic render() {
    return Div()([
      H2()([count]),
      Button().onClick(decrement)(['-']),
      Button().onClick(increment)(['+']),
    ]);
  }
}
Implementers

Constructors

Component()

Properties

attached ↔ bool
getter/setter pair
componentRuntime → ComponentRuntime?
no setter
hashCode → int
The hash code for this object.
no setterinherited
runtime → ComponentRuntime
no setter
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited
styles → List<Stylesheet>
no setter

Methods

attach(ComponentRuntime runtime) → void
detach() → void
morph(void updater()) → void
noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
onMorph() → void
render() → Morphic
Produces the Morphic tree for this component's current state.
toString() → String
A string representation of this object.
inherited
update() → void

Operators

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