ComponentElement class

An Element that composes other Elements.

Rather than creating a RenderObject directly, a ComponentElement creates RenderObjects indirectly by creating other Elements.

Contrast with RenderObjectElement.

Inheritance
Implementers

Constructors

ComponentElement(Widget widget)
Creates an element that uses the given widget as its configuration.

Properties

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.
read-only, inherited
dirty → bool
Returns true if the element has been marked as needing rebuilding.
read-only, inherited
hashCode → int
The hash code for this object. [...]
read-only, inherited
owner → BuildOwner
The object that manages the lifecycle of this element.
read-only, inherited
renderObject → RenderObject
The render object at (or below) this location in the tree. [...]
read-only, inherited
runtimeType → Type
A representation of the runtime type of the object.
read-only, inherited
size → Size
The size of the RenderBox returned by findRenderObject. [...]
read-only, inherited
slot → dynamic
Information set by parent to define where this child fits in its parent's child list. [...]
read-only, inherited
widget → Widget
The configuration for this element.
read-only, inherited

Methods

build() → Widget
Subclasses should override this function to actually call the appropriate build function (e.g., StatelessWidget.build or State.build) for their widget.
@protected
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. [...]
override
mount(Element parent, dynamic newSlot) → void
Add this element to the tree in the given slot of the given parent. [...]
override
performRebuild() → void
Calls the StatelessWidget.build method of the StatelessWidget object (for stateless widgets) or the State.build method of the State object (for stateful widgets) and then updates the widget tree. [...]
override
visitChildren(ElementVisitor visitor) → void
Calls the argument for each child. Must be overridden by subclasses that support having children. [...]
override
activate() → void
Transition from the "inactive" to the "active" lifecycle state. [...]
@mustCallSuper, inherited
ancestorInheritedElementForWidgetOfExactType(Type targetType) → InheritedElement
Obtains the element corresponding to the nearest widget of the given type, which must be the type of a concrete InheritedWidget subclass. [...]
inherited
ancestorRenderObjectOfType(TypeMatcher matcher) → RenderObject
Returns the RenderObject object of the nearest ancestor RenderObjectWidget widget that matches the given TypeMatcher. [...]
inherited
ancestorStateOfType(TypeMatcher matcher) → State<StatefulWidget>
Returns the State object of the nearest ancestor StatefulWidget widget that matches the given TypeMatcher. [...]
inherited
ancestorWidgetOfExactType(Type targetType) → Widget
Returns the nearest ancestor widget of the given type, which must be the type of a concrete Widget subclass. [...]
inherited
attachRenderObject(dynamic newSlot) → void
Add renderObject to the render tree at the location specified by slot. [...]
inherited
deactivate() → void
Transition from the "active" to the "inactive" lifecycle state. [...]
@mustCallSuper, inherited
deactivateChild(Element child) → void
Move the given element to the list of inactive elements and detach its render object from the render tree. [...]
@protected, inherited
debugDeactivated() → void
Called, in debug mode, after children have been deactivated (see deactivate). [...]
@mustCallSuper, inherited
debugDescribeChildren() → List<DiagnosticsNode>
Returns a list of DiagnosticsNode objects describing this node's children. [...]
inherited
debugFillProperties(DiagnosticPropertiesBuilder properties) → void
Add additional properties associated with the node. [...]
inherited
debugGetCreatorChain(int limit) → String
Returns a description of what caused this element to be created. [...]
inherited
debugGetDiagnosticChain() → List<Element>
Returns the parent chain from this element back to the root of the tree. [...]
inherited
debugVisitOnstageChildren(ElementVisitor visitor) → void
Calls the argument for each child considered onstage. [...]
inherited
detachRenderObject() → void
Remove renderObject from the render tree. [...]
inherited
didChangeDependencies() → void
Called when a dependency of this element changes. [...]
@mustCallSuper, inherited
findRenderObject() → RenderObject
The current RenderObject for the widget. If the widget is a RenderObjectWidget, this is the render object that the widget created for itself. Otherwise, it is the render object of the first descendant RenderObjectWidget. [...]
inherited
inflateWidget(Widget newWidget, dynamic newSlot) → Element
Create an element for the given widget and add it as a child of this element in the given slot. [...]
@protected, inherited
inheritFromElement(InheritedElement ancestor, { Object aspect }) → InheritedWidget
Registers this build context with ancestor such that when ancestor's widget changes this build context is rebuilt. [...]
inherited
inheritFromWidgetOfExactType(Type targetType, { Object aspect }) → InheritedWidget
Obtains the nearest widget of the given type, which must be the type of a concrete InheritedWidget subclass, and registers this build context with that widget such that when that widget changes (or a new widget of that type is introduced, or the widget goes away), this build context is rebuilt so that it can obtain new values from that widget. [...]
inherited
markNeedsBuild() → void
Marks the element as dirty and adds it to the global list of widgets to rebuild in the next frame. [...]
inherited
noSuchMethod(Invocation invocation) → dynamic
Invoked when a non-existent method or property is accessed. [...]
inherited
rebuild() → void
Called by the BuildOwner when BuildOwner.scheduleBuildFor has been called to mark this element dirty, by mount when the element is first built, and by update when the widget has changed.
inherited
rootAncestorStateOfType(TypeMatcher matcher) → State<StatefulWidget>
Returns the State object of the furthest ancestor StatefulWidget widget that matches the given TypeMatcher. [...]
inherited
toDiagnosticsNode({String name, DiagnosticsTreeStyle style }) → DiagnosticsNode
Returns a debug representation of the object that is used by debugging tools and by toStringDeep. [...]
inherited
toString({DiagnosticLevel minLevel: DiagnosticLevel.debug }) → String
Returns a string representation of this object.
inherited
toStringDeep({String prefixLineOne: '', String prefixOtherLines, DiagnosticLevel minLevel: DiagnosticLevel.debug }) → String
Returns a string representation of this node and its descendants. [...]
inherited
toStringShallow({String joiner: ', ', DiagnosticLevel minLevel: DiagnosticLevel.debug }) → String
Returns a one-line detailed description of the object. [...]
inherited
toStringShort() → String
A short, textual description of this element.
inherited
unmount() → void
Transition from the "inactive" to the "defunct" lifecycle state. [...]
@mustCallSuper, inherited
update(covariant Widget newWidget) → void
Change the widget used to configure this element. [...]
@mustCallSuper, inherited
updateChild(Element child, Widget newWidget, dynamic newSlot) → Element
Update the given child with the given new configuration. [...]
@protected, inherited
updateSlotForChild(Element child, dynamic newSlot) → void
Change the slot that the given child occupies in its parent. [...]
@protected, inherited
visitAncestorElements(bool visitor(Element element)) → void
Walks the ancestor chain, starting with the parent of this build context's widget, invoking the argument for each ancestor. The callback is given a reference to the ancestor widget's corresponding Element object. The walk stops when it reaches the root widget or when the callback returns false. The callback must not return null. [...]
inherited
visitChildElements(ElementVisitor visitor) → void
Wrapper around visitChildren for BuildContext.
inherited

Operators

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