ObserverElement class abstract

An Element that uses an ObserverComponent as its configuration. You can override willRebuildElement, didRebuildElement and didUnmountElement to execute the required logic.

Inheritance

Constructors

ObserverElement(ObserverComponent component)

Properties

binding → AppBinding
The root component binding that manages the component tree.
no setterinherited
child → Element
The current child of this element.
no setterinherited
component → ObserverComponent
The configuration for this element.
no setteroverride
debugDoingBuild → bool
Whether the component is currently updating the component or render tree.
no setterinherited
depth → int
An integer that is guaranteed to be greater than the parent's, if any. The element at the root of the tree must have a depth greater than 0.
no setterinherited
dirty → bool
no setterinherited
hashCode → int
The hash code for this object.
no setterinherited
lastRenderObjectElement → RenderObjectElement?
no setterinherited
owner → BuildOwner
The root build owner that manages the build cycle.
no setterinherited
parent → Element?
no setterinherited
parentRenderObjectElement → RenderObjectElement?
no setterinherited
prevAncestorSibling → Element?
no setterinherited
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited

Methods

activate() → void
Transition from the "inactive" to the "active" lifecycle state.
inherited
attachNotificationTree() → void
Called in Element.mount and Element.activate to register this element in the notification tree.
inherited
attachRenderObject() → void
inherited
build() → Component?
Subclasses should override this function to return the current configuration of their child.
override
deactivate() → void
Transition from the "active" to the "inactive" lifecycle state.
inherited
deactivateChild(Element child) → void
Move the given element to the list of inactive elements and detach its render object from the render tree.
inherited
dependOnInheritedComponentOfExactType<T extends InheritedComponent>({Object? aspect}) → T?
Obtains the nearest component of the given type T, which must be the type of a concrete InheritedComponent subclass, and registers this build context with that component such that when that component changes (or a new component of that type is introduced, or the component goes away), this build context is rebuilt so that it can obtain new values from that component.
inherited
dependOnInheritedElement(InheritedElement ancestor, {Object? aspect}) → InheritedComponent
Registers this build context with ancestor such that when ancestor's component changes this build context is rebuilt.
inherited
didChangeDependencies() → void
Called when a dependency of this element changes.
inherited
didRebuildElement(Element element) → void
Executed when a child element completed a rebuild.
didUnmountElement(Element element) → void
Executed when a child element is unmounted from the Element tree. You should release any resources associated with the element.
dispatchNotification(Notification notification) → void
Start bubbling this notification at the given build context.
inherited
findAncestorStateOfType<T extends State<StatefulComponent>>() → T?
Returns the State object of the nearest ancestor StatefulComponent component that is an instance of the given type T.
inherited
forgetChild(Element child) → void
Remove the given child from the element's child list, in preparation for the child being reused elsewhere in the element tree.
inherited
getElementForInheritedComponentOfExactType<T extends InheritedComponent>() → InheritedElement?
Obtains the element corresponding to the nearest component of the given type T, which must be the type of a concrete InheritedComponent subclass.
inherited
inflateComponent(Component newComponent, Element? prevSibling) → Element
Create an element for the given component and add it as a child of this element.
inherited
markNeedsBuild() → void
Marks the element as dirty and schedules a rebuild.
inherited
mount(Element? parent, Element? prevSibling) → void
Add this element to the tree as a child of the given parent.
inherited
noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
performRebuild() → void
Cause the component to update itself.
inherited
rebuild() → void
Cause the component to update itself.
inherited
toString() → String
A string representation of this object.
inherited
unmount() → void
Transition from the "inactive" to the "defunct" lifecycle state.
inherited
update(covariant ObserverComponent newComponent) → void
Change the component used to configure this element.
override
updateChild(Element? child, Component? newComponent, Element? prevSibling) → Element?
Update the given child with the given new configuration.
inherited
updateLastChild(Element? child) → void
inherited
updatePrevSibling(Element? prevSibling) → void
inherited
visitAncestorElements(bool visitor(Element element)) → void
Walks the ancestor chain, starting with the parent of this build context's component, invoking the argument for each ancestor. The callback is given a reference to the ancestor component's corresponding Element object. The walk stops when it reaches the root component or when the callback returns false. The callback must not return null.
inherited
visitChildElements(ElementVisitor visitor) → void
Wrapper around visitChildren for BuildContext.
inherited
visitChildren(ElementVisitor visitor) → void
Calls the argument for each child.
inherited
willRebuildElement(Element element) → void
Executed when a child element is the next to rebuild.

Operators

operator ==(Object other) → bool
Compare two components for equality.
inherited