RenderView class

The root of the render tree.

The view represents the total output surface of the render tree and handles bootstrapping the rendering pipeline. The view has a unique child RenderBox, which is required to fill the entire output surface.

This object must be bootstrapped in a specific order:

First, set the configuration (either in the constructor or after construction).
Second, attach the object to a PipelineOwner.
Third, use prepareInitialFrame to bootstrap the layout and paint logic.

After the bootstrapping is complete, the compositeFrame method may be used to obtain the rendered output.

Inheritance

Object
RenderObject
RenderView

Mixed-in types

RenderObjectWithChildMixin<RenderBox>

Constructors

RenderView({RenderBox? child, ViewConfiguration? configuration, required FlutterView view}): Creates the root of the render tree.

Properties

alwaysNeedsCompositing → bool: Whether this render object always needs compositing.
no setterinherited
attached → bool: Whether the render tree this render object belongs to is attached to a PipelineOwner.
no setterinherited
automaticSystemUiAdjustment ↔ bool: Whether Flutter should automatically compute the desired system UI.
getter/setter pair
child ↔ RenderBox?: The render object's unique child.
getter/setter pairinherited
configuration ↔ ViewConfiguration: The constraints used for the root layout.
getter/setter pair
constraints → BoxConstraints: The layout constraints most recently supplied by the parent.
no setteroverride
debugCanParentUseSize → bool: Whether the parent render object is permitted to use this render object's size.
no setterinherited
debugCreator ↔ Object?: The object responsible for creating this render object.
getter/setter pairinherited
debugDisposed → bool?: Whether this has been disposed.
no setterinherited
debugDoingThisLayout → bool: Whether performLayout for this render object is currently running.
no setterinherited
debugDoingThisLayoutWithCallback → bool: Whether invokeLayoutCallback for this render object is currently running.
no setterinherited
debugDoingThisPaint → bool: Whether paint for this render object is currently running.
no setterinherited
debugDoingThisResize → bool: Whether performResize for this render object is currently running.
no setterinherited
debugLayer → ContainerLayer?: In debug mode, the compositing layer that this render object uses to repaint.
no setterinherited
debugLayoutParent → RenderObject?: The RenderObject that's expected to call layout on this RenderObject in its performLayout implementation.
no setterinherited
debugNeedsCompositedLayerUpdate → bool: Whether this render object's layer information is dirty.
no setterinherited
debugNeedsLayout → bool: Whether this render object's layout information is dirty.
no setterinherited
debugNeedsPaint → bool: Whether this render object's paint information is dirty.
no setterinherited
debugNeedsSemanticsUpdate → bool: Whether the semantics of this render object is dirty and await the update.
no setterinherited
debugSemantics → SemanticsNode?: The semantics of this render object.
no setterinherited
depth → int: The depth of this render object in the render tree.
no setterinherited
flutterView → FlutterView: The ui.FlutterView into which this RenderView will render.
no setter
hasConfiguration → bool: Whether a configuration has been set.
no setter
hashCode → int: The hash code for this object.
no setterinherited
isRepaintBoundary → bool: Whether this render object repaints separately from its parent.
no setteroverride
layer ↔ ContainerLayer?: The compositing layer that this render object uses to repaint.
getter/setter pairinherited
needsCompositing → bool: Whether we or one of our descendants has a compositing layer.
no setterinherited
owner → PipelineOwner?: The owner for this render object (null if unattached).
no setterinherited
paintBounds → Rect: An estimate of the bounds within which this render object will paint. Useful for debugging flags such as debugPaintLayerBordersEnabled.
no setteroverride
parent → RenderObject?: The parent of this render object in the render tree.
no setterinherited
parentData ↔ ParentData?: Data for use by the parent render object.
getter/setter pairinherited
runtimeType → Type: A representation of the runtime type of the object.
no setterinherited
semanticBounds → Rect: The bounding box, in the local coordinate system, of this object, for accessibility purposes.
no setteroverride
semanticsParent → RenderObject?: The semantics parent of this render object in the semantics tree.
no setterinherited
size → Size: The current layout size of the view.
no setter
sizedByParent → bool: Whether the constraints are the only input to the sizing algorithm (in particular, child nodes have no impact).
no setterinherited

Methods

adoptChild(RenderObject child) → void: Called by subclasses when they decide a render object is a child.
inherited
applyPaintTransform(covariant RenderBox child, Matrix4 transform) → void: Applies the transform that would be applied when painting the given child to the given matrix.
override
assembleSemanticsNode(SemanticsNode node, SemanticsConfiguration config, Iterable<SemanticsNode> children) → void: Assemble the SemanticsNode for this RenderObject.
inherited
attach(PipelineOwner owner) → void: Mark this render object as attached to the given owner.
inherited
clearSemantics() → void: Removes all semantics from this render object and its descendants.
inherited
compositeFrame() → void: Uploads the composited layer tree to the engine.
debugAssertDoesMeetConstraints() → void: Verify that the object's constraints are being met. Override this function in a subclass to verify that your state matches the constraints object. This function is only called when asserts are enabled (i.e. in debug mode) and only when needsLayout is false. If the constraints are not met, it should assert or throw an exception.
override
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.
override
debugPaint(PaintingContext context, Offset offset) → void: Override this method to paint debugging information.
inherited
debugRegisterRepaintBoundaryPaint({bool includedParent = true, bool includedChild = false}) → void: Called, in debug mode, if isRepaintBoundary is true, when either the this render object or its parent attempt to paint.
inherited
debugResetSize() → void: If a subclass has a "size" (the state controlled by parentUsesSize, whatever it is in the subclass, e.g. the actual size property of RenderBox), and the subclass verifies that in debug mode this "size" property isn't used when debugCanParentUseSize isn't set, then that subclass should override debugResetSize to reapply the current values of debugCanParentUseSize to that state.
inherited
debugValidateChild(RenderObject child) → bool: Checks whether the given render object has the correct runtimeType to be a child of this render object.
inherited
describeApproximatePaintClip(covariant RenderObject child) → Rect?: Returns a rect in this object's coordinate system that describes the approximate bounding box of the clip rect that would be applied to the given child during the paint phase, if any.
inherited
describeForError(String name, {DiagnosticsTreeStyle style = DiagnosticsTreeStyle.shallow}) → DiagnosticsNode: Adds a debug representation of a RenderObject optimized for including in error messages.
inherited
describeSemanticsClip(covariant RenderObject? child) → Rect?: Returns a rect in this object's coordinate system that describes which SemanticsNodes produced by the child should be included in the semantics tree. SemanticsNodes from the child that are positioned outside of this rect will be dropped. Child SemanticsNodes that are positioned inside this rect, but outside of describeApproximatePaintClip will be included in the tree marked as hidden. Child SemanticsNodes that are inside of both rect will be included in the tree as regular nodes.
inherited
describeSemanticsConfiguration(SemanticsConfiguration config) → void: Report the semantics of this node, for example for accessibility purposes.
inherited
detach() → void: Mark this render object as detached from its PipelineOwner.
inherited
dispose() → void: Release any resources held by this render object.
inherited
dropChild(RenderObject child) → void: Called by subclasses when they decide a render object is no longer a child.
inherited
getTransformTo(RenderObject? target) → Matrix4: Applies the paint transform from this RenderObject to the target RenderObject.
inherited
handleEvent(PointerEvent event, covariant HitTestEntry<HitTestTarget> entry) → void: Override this method to handle pointer events that hit this render object.
inherited
hitTest(HitTestResult result, {required Offset position}) → bool: Determines the set of render objects located at the given position.
invokeLayoutCallback<T extends Constraints>(LayoutCallback<T> callback) → void: Allows mutations to be made to this object's child list (and any descendants) as well as to any other dirty nodes in the render tree owned by the same PipelineOwner as this object. The callback argument is invoked synchronously, and the mutations are allowed only during that callback's execution.
inherited
layout(Constraints constraints, {bool parentUsesSize = false}) → void: Compute the layout for this render object.
inherited
markNeedsCompositedLayerUpdate() → void: Mark this render object as having changed a property on its composited layer.
inherited
markNeedsCompositingBitsUpdate() → void: Mark the compositing state for this render object as dirty.
inherited
markNeedsLayout() → void: Mark this render object's layout information as dirty, and either register this object with its PipelineOwner, or defer to the parent, depending on whether this object is a relayout boundary or not respectively.
inherited
markNeedsLayoutForSizedByParentChange() → void: Mark this render object's layout information as dirty (like markNeedsLayout), and additionally also handle any necessary work to handle the case where sizedByParent has changed value.
inherited
markNeedsPaint() → void: Mark this render object as having changed its visual appearance.
inherited
markNeedsSemanticsUpdate() → void: Mark this node as needing an update to its semantics description.
inherited
markParentNeedsLayout() → void: Mark this render object's layout information as dirty, and then defer to the parent.
inherited
noSuchMethod(Invocation invocation) → dynamic: Invoked when a nonexistent method or property is accessed.
inherited
paint(PaintingContext context, Offset offset) → void: Paint this render object into the given context at the given offset.
override
paintsChild(covariant RenderObject child) → bool: Whether the given child would be painted if paint were called.
inherited
performLayout() → void: Do the work of computing the layout for this render object.
override
performResize() → void: Updates the render objects size using only the constraints.
override
prepareInitialFrame() → void: Bootstrap the rendering pipeline by preparing the first frame.
reassemble() → void: Cause the entire subtree rooted at the given RenderObject to be marked dirty for layout, paint, etc, so that the effects of a hot reload can be seen, or so that the effect of changing a global debug flag (such as debugPaintSizeEnabled) can be applied.
inherited
redepthChild(RenderObject child) → void: Adjust the depth of the given child to be greater than this node's own depth.
inherited
redepthChildren() → void: Adjust the depth of this node's children, if any.
inherited
replaceRootLayer(OffsetLayer rootLayer) → void: Replace the layer. This is only valid for the root of a render object subtree (whatever object scheduleInitialPaint was called on).
inherited
scheduleInitialLayout() → void: Bootstrap the rendering pipeline by scheduling the very first layout.
inherited
scheduleInitialPaint(ContainerLayer rootLayer) → void: Bootstrap the rendering pipeline by scheduling the very first paint.
inherited
scheduleInitialSemantics() → void: Bootstrap the semantics reporting mechanism by marking this node as needing a semantics update.
inherited
sendSemanticsEvent(SemanticsEvent semanticsEvent) → void: Sends a SemanticsEvent associated with this render object's SemanticsNode.
inherited
setupParentData(covariant RenderObject child) → void: Override to setup parent data correctly for your children.
inherited
showOnScreen({RenderObject? descendant, Rect? rect, Duration duration = Duration.zero, Curve curve = Curves.ease}) → void: Attempt to make (a portion of) this or a descendant RenderObject visible on screen.
inherited
toDiagnosticsNode({String? name, DiagnosticsTreeStyle? style}) → DiagnosticsNode: Returns a debug representation of the object that is used by debugging tools and by DiagnosticsNode.toStringDeep.
inherited
toString({DiagnosticLevel minLevel = DiagnosticLevel.info}) → String: A string representation of this object.
inherited
toStringDeep({String prefixLineOne = '', String? prefixOtherLines = '', DiagnosticLevel minLevel = DiagnosticLevel.debug, int wrapWidth = 65}) → String: Returns a description of the tree rooted at this node. If the prefix argument is provided, then every line in the output will be prefixed by that string.
inherited
toStringShallow({String joiner = ', ', DiagnosticLevel minLevel = DiagnosticLevel.debug}) → String: Returns a one-line detailed description of the render object. This description is often somewhat long.
inherited
toStringShort() → String: Returns a human understandable name.
inherited
updateCompositedLayer({required covariant OffsetLayer? oldLayer}) → OffsetLayer: Update the composited layer owned by this render object.
inherited
updateSemantics(SemanticsUpdate update) → void: Sends the provided ui.SemanticsUpdate to the ui.FlutterView associated with this RenderView.
visitChildren(RenderObjectVisitor visitor) → void: Calls visitor for each immediate child of this render object.
inherited
visitChildrenForSemantics(RenderObjectVisitor visitor) → void: Called when collecting the semantics of this node.
inherited

Operators

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

Static Methods

debugAddPaintCallback(DebugPaintCallback callback) → void: Registers a DebugPaintCallback that is called every time a RenderView repaints in debug mode.
debugRemovePaintCallback(DebugPaintCallback callback) → void: Removes a callback registered with debugAddPaintCallback.