Component class

Components are the basic building blocks for your game.

Components can be for example bullets flying on the screen, a spaceship, a timer or an enemy. Anything that either needs to be rendered and/or updated is a good idea to have as a Component, since update and render will be called automatically once the component is added to the component tree in your game (with game.add).

Implementers

Available Extensions

ComponentExt

Constructors

Component({int? priority})

Properties

children → ComponentSet: The children of the current component.
no setter
debugColor ↔ Color: The color that the debug output should be rendered with.
getter/setter pair
debugCoordinatesPrecision → int?: How many decimal digits to print when displaying coordinates in the debug mode. Setting this to null will suppress all coordinates from the output.
no setter
debugMode ↔ bool: Returns whether this Component is in debug mode or not. When a child is added to the Component it gets the same debugMode as its parent has when it is prepared.
getter/setter pair
debugPaint → Paint: The debugColor represented as a Paint object.
no setter
debugTextPaint → TextPaint: Returns a TextPaint object with the debugColor set as color for the text.
no setter
hasChildren → bool: no setter
hashCode → int: The hash code for this object.
no setterinherited
hasPendingLifecycleEvents → bool: no setter
isLoaded → bool: Whether this component has completed its onLoad step.
no setter
isMounted → bool: Whether this component is currently added to a component tree.
no setter
lifecycle → _LifecycleManager: no setter
loaded → Future<void>: A future that will complete once this component has finished loading.
no setter
mounted → Future<void>: A future that will complete once the component is mounted on its parent
no setter
parent → Component?: The current parent of the component, or null if there is none.
no setter
positionType ↔ PositionType: What coordinate system this component should respect (i.e. should it observe camera, viewport, or use the raw canvas).
getter/setter pair
priority ↔ int: Render priority of this component. This allows you to control the order in which your components are rendered.
getter/setter pair
runtimeType → Type: A representation of the runtime type of the object.
no setterinherited
shouldRemove ↔ bool: Whether this component should be removed or not.
getter/setter pair

Methods

add(Component component) → Future<void>?: Schedules component to be added as a child to this component.
addAll(Iterable<Component> components) → Future<void>: A convenience method to add multiple children at once.
addToParent(Component parent) → Future<void>?: Adds this component to the provided parent (see add for details).
ancestors({bool includeSelf = false}) → Iterable<Component>: An iterator producing this component's parent, then its parent's parent, then the great-grand-parent, and so on, until it reaches a component without a parent.
changeParent(Component newParent) → void: Changes the current parent for another parent and prepares the tree under the new root.
changePriorityWithoutResorting(int priority) → void: Usually this is not something that the user would want to call since the component list isn't re-ordered when it is called. See FlameGame.changePriority instead.
contains(Component c) → bool: Whether the children list contains the given component.
containsPoint(Vector2 point) → bool: Called to check whether the point is to be counted as within the component It needs to be overridden to have any effect, like it is in PositionComponent.
createComponentSet() → ComponentSet: This method creates the children container for the current component. Override this method if you need to have a custom ComponentSet within a particular class.
descendants({bool includeSelf = false, bool reversed = false}) → Iterable<Component>: Recursively enumerates all nested children.
eventPosition(PositionInfo info) → Vector2
findGame() → Game?
findParent<T extends Component>() → T?: Returns the closest parent further up the hierarchy that satisfies type=T, or null if no such parent can be found.
firstChild<T extends Component>() → T?: Returns the first child that matches the given type T.
handleResize(Vector2 size) → void
lastChild<T extends Component>() → T?: Returns the last child that matches the given type T.
noSuchMethod(Invocation invocation) → dynamic: Invoked when a nonexistent method or property is accessed.
inherited
onGameResize(Vector2 size) → void: Called whenever the size of the top-level Canvas changes.
onLoad() → Future<void>?: Late initialization method for Component.
onMount() → void: Called when the component is added to its parent.
onRemove() → void: Called right before the component is removed from the game.
processPendingLifecycleEvents() → void: Attempt to resolve any pending lifecycle events on this component.
propagateToChildren<T extends Component>(bool handler(T), {bool includeSelf = false}) → bool: This method first calls the passed handler on the leaves in the tree, the children without any children of their own. Then it continues through all other children. The propagation continues until the handler returns false, which means "do not continue", or when the handler has been called with all children.
remove(Component component) → void: Removes a component from the component tree, calling onRemove for it and its children.
removeAll(Iterable<Component> components) → void: Removes all the children in the list and calls onRemove for all of them and their children.
removeFromParent() → void: Remove the component from its parent in the next tick.
render(Canvas canvas) → void
renderDebugMode(Canvas canvas) → void
renderTree(Canvas canvas) → void
reorderChildren() → void: Call this if any of this component's children priorities have changed at runtime.
setMounted() → void
toString() → String: A string representation of this object.
inherited
update(double dt) → void: This method is called periodically by the game engine to request that your component updates itself.
updateTree(double dt) → void: This method traverses the component tree and calls update on all its children according to their priority order, relative to the priority of the direct siblings, not the children or the ancestors.

Operators

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

Static Properties

childrenFactory ↔ ComponentSetFactory: Component.childrenFactory is the default method for creating children containers within all components. Replace this method if you want to have customized (non-default) ComponentSet instances in your project.
getter/setter pair
staticGameInstance ↔ Game?: getter/setter pair