The Flutter rendering tree.

To use, import package:flutter/rendering.dart.

The RenderObject hierarchy is used by the Flutter Widgets library to implement its layout and painting back-end. Generally, while you may use custom RenderBox classes for specific effects in your applications, most of the time your only interaction with the RenderObject hierarchy will be in debugging layout issues.

If you are developing your own library or application directly on top of the rendering library, then you will want to have a binding (see BindingBase). You can use RenderingFlutterBinding, or you can create your own binding. If you create your own binding, it needs to import at least SchedulerBinding, GestureBinding, ServicesBinding, and RendererBinding. The rendering library does not automatically create a binding, but relies on one being initialized with those features.

Classes

AbstractNode
An abstract node in a tree. [...]
BackdropFilterLayer
A composited layer that applies a filter to the existing contents of the scene.
Border
A border of a box, comprised of four sides. [...]
BorderRadius
An immutable set of radii for each corner of a rectangle. [...]
BorderSide
A side of a border of a box. [...]
BoxConstraints
Immutable layout constraints for RenderBox layout. [...]
BoxDecoration
An immutable description of how to paint a box. [...]
BoxHitTestEntry
A hit test entry used by RenderBox.
BoxPainter
A stateful class that can paint a particular Decoration. [...]
BoxParentData
Parent data used by RenderBox and its subclasses.
BoxShadow
A shadow cast by a box. [...]
Canvas
An interface for recording graphical operations. [...]
ClipPathLayer
A composite layer that clips its children using a path.
ClipRectLayer
A composite layer that clips its children using a rectangle.
ClipRRectLayer
A composite layer that clips its children using a rounded rectangle.
Color
An immutable 32 bit color value in ARGB format. [...]
ColorFilter
A description of a color filter to apply when drawing a shape or compositing a layer with a particular Paint. A color filter is a function that takes two colors, and outputs one color. When applied during compositing, it is independently applied to each pixel of the layer being drawn before the entire layer is merged with the destination. [...]
ColorSwatch
A color that has a small table of related colors called a "swatch". [...]
Constraints
An abstract set of layout constraints. [...]
ContainerBoxParentData
Abstract ParentData subclass for RenderBox subclasses that want the ContainerRenderObjectMixin. [...]
ContainerLayer
A composited layer that has a list of children. [...]
ContainerParentDataMixin
Parent data to support a doubly-linked list of children.
ContainerRenderObjectMixin
Generic mixin for render objects with a list of children. [...]
CustomClipper
An interface for providing custom clips. [...]
CustomPainter
The interface used by CustomPaint (in the widgets library) and RenderCustomPaint (in the rendering library). [...]
Decoration
A description of a box decoration (a decoration applied to a Rect). [...]
DecorationImage
An image for a box decoration. [...]
EdgeInsets
An immutable set of offsets in each of the four cardinal directions. [...]
FittedSizes
The pair of sizes returned by applyBoxFit.
FixedColumnWidth
Sizes the column to a specific number of pixels. [...]
FlexColumnWidth
Sizes the column by taking a part of the remaining space once all the other columns have been laid out. [...]
FlexParentData
Parent data for use with RenderFlex.
FloatingHeaderSnapConfiguration
Specifies how a floating header is to be "snapped" (animated) into or out of view. [...]
FlowDelegate
A delegate that controls the appearance of a flow layout. [...]
FlowPaintingContext
A context in which a FlowDelegate paints. [...]
FlowParentData
Parent data for use with RenderFlow. [...]
FlutterErrorDetailsForRendering
Variant of FlutterErrorDetails with extra fields for the rendering library.
FlutterLogoDecoration
An immutable description of how to paint Flutter's logo.
FollowerLayer
A composited layer that applies a transformation matrix to its children such that they are positioned to match a LeaderLayer. [...]
FontWeight
The thickness of the glyphs used to draw the text
FractionalOffset
An offset that's expressed as a fraction of a Size. [...]
FractionalOffsetTween
An interpolation between two fractional offsets. [...]
FractionColumnWidth
Sizes the column to a fraction of the table's constraints' maxWidth. [...]
Gradient
A 2D gradient. [...]
HitTestEntry
Data collected during a hit test about a specific HitTestTarget. [...]
HitTestResult
The result of performing a hit test.
HSVColor
A color represented using alpha, hue, saturation, and value. [...]
ImageConfiguration
Configuration information passed to the ImageProvider.resolve method to select a specific image. [...]
ImageShader
A shader (as used by Paint.shader) that tiles an image.
IntrinsicColumnWidth
Sizes the column according to the intrinsic dimensions of all the cells in that column. [...]
Layer
A composited layer. [...]
An object that a LeaderLayer can register with. [...]
LeaderLayer
A composited layer that can be followed by a FollowerLayer. [...]
LinearGradient
A 2D linear gradient. [...]
ListBodyParentData
Parent data for use with RenderListBody.
MaskFilter
A mask filter to apply to shapes as they are painted. A mask filter is a function that takes a bitmap of color pixels, and returns another bitmap of color pixels. [...]
Matrix4
4D Matrix. Values are stored in column major order.
MatrixUtils
Utility functions for working with matrices.
MaxColumnWidth
Sizes the column such that it is the size that is the maximum of two column width specifications. [...]
MinColumnWidth
Sizes the column such that it is the size that is the minimum of two column width specifications. [...]
MultiChildLayoutDelegate
A delegate that controls the layout of multiple children. [...]
MultiChildLayoutParentData
ParentData used by RenderCustomMultiChildLayoutBox.
Offset
An immutable 2D floating-point offset. [...]
OffsetLayer
A layer that is displayed at an offset from its parent layer. [...]
OpacityLayer
A composited layer that makes its children partially transparent.
Paint
A description of the style to use when drawing on a Canvas. [...]
PaintingContext
A place to paint. [...]
ParentData
Base class for data associated with a RenderObject by its parent. [...]
Path
A complex, one-dimensional subset of a plane. [...]
PerformanceOverlayLayer
A layer that indicates to the compositor that it should display certain performance statistics within it. [...]
PhysicalModelLayer
A composited layer that uses a physical model to producing lighting effects. [...]
PictureLayer
A composited layer containing a Picture. [...]
PipelineOwner
The pipeline owner manages the rendering pipeline. [...]
PointerCancelEvent
The input from the pointer is no longer directed towards this receiver.
PointerDownEvent
The pointer has made contact with the device.
PointerEvent
Base class for touch, stylus, or mouse events. [...]
PointerMoveEvent
The pointer has moved with respect to the device while the pointer is in contact with the device. [...]
PointerUpEvent
The pointer has stopped making contact with the device.
RadialGradient
A 2D radial gradient. [...]
Radius
A radius for either circular or elliptical shapes.
Rect
An immutable, 2D, axis-aligned, floating-point rectangle whose coordinates are relative to a given origin. [...]
RelativeRect
An immutable 2D, axis-aligned, floating-point rectangle whose coordinates are given relative to another rectangle's edges, known as the container. Since the dimensions of the rectangle are relative to those of the container, this class has no width and height members. To determine the width or height of the rectangle, convert it to a Rect using toRect() (passing the container's own Rect), and then examine that object. [...]
RenderAbsorbPointer
A render object that absorbs pointers during hit testing. [...]
RenderAbstractViewport
An interface for render objects that are bigger on the inside. [...]
RenderAligningShiftedBox
Abstract class for one-child-layout render boxes that use a FractionalOffset to align their children.
RenderAnimatedSize
A render object that animates its size to its child's size over a given duration and with a given curve. If the child's size itself animates (i.e. if it changes size two frames in a row, as opposed to abruptly changing size in one frame then remaining that size in subsequent frames), this render object sizes itself to fit the child instead of animating itself. [...]
RenderAspectRatio
Attempts to size the child to a specific aspect ratio. [...]
RenderBackdropFilter
Applies a filter to the existing painted content and then paints child. [...]
RenderBaseline
Shifts the child down such that the child's baseline (or the bottom of the child, if the child has no baseline) is baseline logical pixels below the top of this box, then sizes this box to contain the child. [...]
RenderBlockSemantics
Causes the semantics of all earlier render objects below the same semantic boundary to be dropped. [...]
RenderBox
A render object in a 2D cartesian coordinate system. [...]
RenderBoxContainerDefaultsMixin
A mixin that provides useful default behaviors for boxes with children managed by the ContainerRenderObjectMixin mixin. [...]
RenderClipOval
Clips its child using an oval. [...]
RenderClipPath
Clips its child using a path. [...]
RenderClipRect
Clips its child using a rectangle. [...]
RenderClipRRect
Clips its child using a rounded rectangle. [...]
RenderConstrainedBox
Imposes additional constraints on its child. [...]
RenderConstrainedOverflowBox
A render object that imposes different constraints on its child than it gets from its parent, possibly allowing the child to overflow the parent. [...]
RenderCustomMultiChildLayoutBox
Defers the layout of multiple children to a delegate. [...]
RenderCustomPaint
Provides a canvas on which to draw during the paint phase. [...]
RenderCustomSingleChildLayoutBox
Defers the layout of its single child to a delegate. [...]
RenderDecoratedBox
Paints a Decoration either before or after its child paints.
RenderEditable
Displays some text in a scrollable container with a potentially blinking cursor and with gesture recognizers. [...]
RendererBinding
The glue between the render tree and the Flutter engine.
RenderErrorBox
A render object used as a placeholder when an error occurs. [...]
RenderExcludeSemantics
Excludes this subtree from the semantic tree. [...]
RenderFittedBox
Scales and positions its child within itself according to fit.
RenderFlex
Displays its children in a one-dimensional array. [...]
RenderFlow
Implements the flow layout algorithm. [...]
RenderFollowerLayer
Transform the child so that its origin is offset from the orign of the RenderLeaderLayer with the same LayerLink. [...]
RenderFractionallySizedOverflowBox
Sizes its child to a fraction of the total available space. [...]
RenderFractionalTranslation
Applies a translation transformation before painting its child. [...]
RenderIgnorePointer
A render object that is invisible during hit testing. [...]
RenderImage
An image in the render tree. [...]
RenderIndexedStack
Implements the same layout algorithm as RenderStack but only paints the child specified by index. [...]
RenderingFlutterBinding
A concrete binding for applications that use the Rendering framework directly. This is the glue that binds the framework to the Flutter engine. [...]
RenderIntrinsicHeight
Sizes its child to the child's intrinsic height. [...]
RenderIntrinsicWidth
Sizes its child to the child's intrinsic width. [...]
RenderLeaderLayer
Provides an anchor for a RenderFollowerLayer. [...]
RenderLimitedBox
Constrains the child's BoxConstraints.maxWidth and BoxConstraints.maxHeight if they're otherwise unconstrained. [...]
RenderListBody
Displays its children sequentially along a given axis, forcing them to the dimensions of the parent in the other axis. [...]
RenderMergeSemantics
Causes the semantics of all descendants to be merged into this node such that the entire subtree becomes a single leaf in the semantics tree. [...]
RenderMetaData
Holds opaque meta data in the render tree. [...]
RenderObject
An object in the render tree. [...]
RenderObjectWithChildMixin
Generic mixin for render objects with one child. [...]
RenderOffstage
Lays the child out as if it was in the tree, but without painting anything, without making the child available for hit testing, and without taking any room in the parent.
RenderOpacity
Makes its child partially transparent. [...]
RenderPadding
Insets its child by the given padding. [...]
RenderParagraph
A render object that displays a paragraph of text
RenderPerformanceOverlay
Displays performance statistics. [...]
RenderPhysicalModel
Creates a physical model layer that clips its children to a rounded rectangle. [...]
RenderPointerListener
Calls callbacks in response to pointer events. [...]
RenderPositionedBox
Positions its child using a FractionalOffset. [...]
RenderProxyBox
A base class for render objects that resemble their children. [...]
RenderProxyBoxMixin
Implementation of RenderProxyBox. [...]
RenderProxyBoxWithHitTestBehavior
A RenderProxyBox subclass that allows you to customize the hit-testing behavior.
RenderRepaintBoundary
Creates a separate display list for its child. [...]
RenderRotatedBox
Rotates its child by a integral number of quarter turns. [...]
RenderSemanticsAnnotations
Add annotations to the SemanticsNode for this subtree.
RenderSemanticsGestureHandler
Listens for the specified gestures from the semantics server (e.g. an accessibility tool).
RenderShaderMask
Applies a mask generated by a Shader to its child. [...]
RenderShiftedBox
Abstract class for one-child-layout render boxes that provide control over the child's position.
RenderShrinkWrappingViewport
A render object that is bigger on the inside and shrink wraps its children in the main axis. [...]
RenderSizedOverflowBox
A render box that is a specific size but passes its original constraints through to its child, which will probably overflow.
RenderSliver
Base class for the render objects that implement scroll effects in viewports. [...]
RenderSliverBoxChildManager
A delegate used by RenderSliverMultiBoxAdaptor to manage its children. [...]
RenderSliverFillRemaining
A sliver that contains a single box child that fills the remaining space in the viewport. [...]
RenderSliverFillViewport
A sliver that contains multiple box children that each fill the viewport. [...]
RenderSliverFixedExtentBoxAdaptor
A sliver that contains multiple box children that have the same extent in the main axis. [...]
RenderSliverFixedExtentList
A sliver that places multiple box children with the same main axis extent in a linear array. [...]
RenderSliverFloatingPersistentHeader
RenderSliverFloatingPinnedPersistentHeader
RenderSliverGrid
A sliver that places multiple box children in a two dimensional arrangement. [...]
RenderSliverHelpers
Mixin for RenderSliver subclasses that provides some utility functions.
RenderSliverList
A sliver that places multiple box children in a linear array along the main axis. [...]
RenderSliverMultiBoxAdaptor
A sliver with multiple box children. [...]
RenderSliverPadding
Inset a RenderSliver, applying padding on each side. [...]
RenderSliverPersistentHeader
RenderSliverPinnedPersistentHeader
A sliver with a RenderBox child which never scrolls off the viewport in the positive scroll direction, and which first scrolls on at a full size but then shrinks as the viewport continues to scroll. [...]
RenderSliverScrollingPersistentHeader
A sliver with a RenderBox child which scrolls normally, except that when it hits the leading edge (typically the top) of the viewport, it shrinks to a minimum size before continuing to scroll. [...]
RenderSliverSingleBoxAdapter
An abstract class for RenderSlivers that contains a single RenderBox. [...]
RenderSliverToBoxAdapter
A RenderSliver that contains a single RenderBox. [...]
RenderStack
Implements the stack layout algorithm [...]
RenderTable
A table where the columns and rows are sized to fit the contents of the cells.
RenderTransform
Applies a transformation before painting its child.
RenderView
The root of the render tree. [...]
RenderViewport
A render object that is bigger on the inside. [...]
RenderViewportBase
A base class for render objects that are bigger on the inside. [...]
RenderWrap
Displays its children in multiple horizontal or vertical runs. [...]
RRect
An immutable rounded rectangle with the custom radii for all four corners.
RSTransform
A transform consisting of a translation, a rotation, and a uniform scale. [...]
SemanticsAction
The possible actions that can be conveyed from the operating system accessibility APIs to a semantics node.
SemanticsActionHandler
Interface for RenderObjects to implement when they want to support being tapped, etc. [...]
SemanticsData
Summary information about a SemanticsNode object. [...]
SemanticsHandle
A reference to the semantics tree. [...]
SemanticsNode
A node that represents some semantic data. [...]
SemanticsOwner
Owns SemanticsNode objects and notifies listeners of changes to the render tree semantics. [...]
Shader
Base class for objects such as Gradient and ImageShader which correspond to shaders as used by Paint.shader.
ShaderMaskLayer
A composited layer that applies a shader to its children.
SingleChildLayoutDelegate
A delegate for computing the layout of a render object with a single child. [...]
Size
Holds a 2D floating-point size. [...]
SliverConstraints
Immutable layout constraints for RenderSliver layout. [...]
SliverGeometry
Describes the amount of space occupied by a RenderSliver. [...]
SliverGridDelegate
Controls the layout of tiles in a grid. [...]
SliverGridDelegateWithFixedCrossAxisCount
Creates grid layouts with a fixed number of tiles in the cross axis. [...]
SliverGridDelegateWithMaxCrossAxisExtent
Creates grid layouts with tiles that have a maximum cross-axis extent. [...]
SliverGridGeometry
Describes the placement of a child in a RenderSliverGrid. [...]
SliverGridLayout
The size and position of all the tiles in a RenderSliverGrid. [...]
SliverGridParentData
Parent data structure used by RenderSliverGrid.
SliverGridRegularTileLayout
A SliverGridLayout that uses equally sized and spaced tiles. [...]
SliverHitTestEntry
A hit test entry used by RenderSliver. [...]
SliverLogicalContainerParentData
Parent data for slivers that have multiple children and that position their children using layout offsets.
SliverLogicalParentData
Parent data structure used by parents of slivers that position their children using layout offsets. [...]
SliverMultiBoxAdaptorParentData
Parent data structure used by RenderSliverMultiBoxAdaptor.
SliverPhysicalContainerParentData
Parent data for slivers that have multiple children and that position their children using absolute coordinates.
SliverPhysicalParentData
Parent data structure used by parents of slivers that position their children using absolute coordinates. [...]
StackParentData
Parent data for use with RenderStack.
TableBorder
Border specification for RenderTable. [...]
TableCellParentData
Parent data used by RenderTable for its children.
TableColumnWidth
Base class to describe how wide a column in a RenderTable should be. [...]
TextDecoration
A linear decoration to draw near the text.
TextPainter
An object that paints a TextSpan tree into a Canvas. [...]
TextSelectionPoint
Represents the coordinates of the point in a selection, and the text direction at that point, relative to top left of the RenderEditable that holds the selection.
TextSpan
An immutable span of text. [...]
TextStyle
An immutable style in which paint text. [...]
TransformLayer
A composited layer that applies a given transformation matrix to its children. [...]
ViewConfiguration
The layout constraints for the root render object.
ViewportOffset
Which part of the content inside the viewport should be visible. [...]
WrapParentData
Parent data for use with RenderWrap.

Properties

debugCheckIntrinsicSizes bool
Check the intrinsic sizes of each RenderBox during layout. [...]
read / write
debugCurrentRepaintColor HSVColor
The current color to overlay when repainting a layer.
read / write
debugPaintAlphabeticBaselineColor Color
The color to use when painting alphabetic baselines.
read / write
debugPaintBaselinesEnabled bool
Causes each RenderBox to paint a line at each of its baselines.
read / write
debugPaintBoxArrowColor Color
The color to use when painting the arrows used to show RenderPositionedBox alignment.
read / write
debugPaintIdeographicBaselineColor Color
The color to use when painting ideographic baselines.
read / write
debugPaintLayerBordersColor Color
The color to use when painting Layer borders.
read / write
debugPaintLayerBordersEnabled bool
Causes each Layer to paint a box around its bounds.
read / write
debugPaintPaddingColor Color
The color to use when painting RenderPadding edges. [...]
read / write
debugPaintPaddingInnerEdgeColor Color
The color to use when painting RenderPadding edges. This color is painted on top of debugPaintPaddingColor. [...]
read / write
debugPaintPointersColorValue int
The color to use when reporting pointers for debugPaintPointersEnabled.
read / write
debugPaintPointersEnabled bool
Causes objects like RenderPointerListener to flash while they are being tapped. This can be useful to see how large the hit box is, e.g. when debugging buttons that are harder to hit than expected. [...]
read / write
debugPaintSizeColor Color
The color to use when painting RenderObject bounds.
read / write
debugPaintSizeEnabled bool
Causes each RenderBox to paint a box around its bounds, and some extra boxes, such as RenderPadding, to draw construction lines.
read / write
debugPaintSliverArrowColor Color
The color to use when painting the arrows used to show RenderSliver alignment.
read / write
debugPaintSpacingColor Color
The color to use when painting some boxes that just add space (e.g. an empty RenderConstrainedBox or RenderPadding). [...]
read / write
debugPrint DebugPrintCallback
Prints a message to the console, which you can access using the "flutter" tool's "logs" command ("flutter logs"). [...]
read / write
debugPrintMarkNeedsLayoutStacks bool
Log the call stacks that mark render objects as needing layout. [...]
read / write
debugPrintMarkNeedsPaintStacks bool
Log the call stacks that mark render objects as needing paint.
read / write
debugProfilePaintsEnabled bool
Adds dart:developer.Timeline events for every RenderObject painted. [...]
read / write
debugRepaintRainbowEnabled bool
Overlay a rotating set of colors when repainting layers in checked mode.
read / write
debugRepaintRainbowHueIncrement double
The amount to increment the hue of the current repaint color.
read / write
debugRepaintTextRainbowEnabled bool
Overlay a rotating set of colors when repainting text in checked mode.
read / write

Functions

applyBoxFit(BoxFit fit, Size inputSize, Size outputSize) FittedSizes
Apply a BoxFit value. [...]
applyGrowthDirecitonToScrollDirection(ScrollDirection scrollDirection, GrowthDirection growthDirection) ScrollDirection
Flips the ScrollDirection if the GrowthDirection is GrowthDirection.reverse. [...]
applyGrowthDirectionToAxisDirection(AxisDirection axisDirection, GrowthDirection growthDirection) AxisDirection
Flips the AxisDirection if the GrowthDirection is GrowthDirection.reverse. [...]
axisDirectionIsReversed(AxisDirection axisDirection) bool
Returns whether travelling along the given axis direction visits coordinates along that axis in numerically decreasing order. [...]
axisDirectionToAxis(AxisDirection axisDirection) Axis
Returns the Axis that contains the given AxisDirection. [...]
debugAssertAllRenderVarsUnset(String reason, { bool debugCheckIntrinsicSizesOverride: false }) bool
Returns true if none of the rendering library debug variables have been changed. [...]
debugDescribeTransform(Matrix4 transform) List<String>
Returns a list of strings representing the given transform in a format useful for RenderObject.debugFillDescription. [...]
debugDumpLayerTree() → void
Prints a textual representation of the entire layer tree.
debugDumpRenderTree() → void
Prints a textual representation of the entire render tree.
debugDumpSemanticsTree() → void
Prints a textual representation of the entire semantics tree. This will only work if there is a semantics client attached. Otherwise, the tree is empty and this will print "null".
debugPaintPadding(Canvas canvas, Rect outerRect, Rect innerRect, { double outlineWidth: 2.0 }) → void
Paint padding using the debugPaintPaddingColor, debugPaintPaddingInnerEdgeColor, and debugPaintSpacingColor colors. [...]
flipAxisDirection(AxisDirection axisDirection) AxisDirection
Returns the opposite of the given AxisDirection. [...]
flipScrollDirection(ScrollDirection direction) ScrollDirection
Returns the opposite of the given ScrollDirection. [...]
hashList(Iterable<Object> arguments) int
Combine the Object.hashCode values of an arbitrary number of objects from an Iterable into one value. This function will return the same value if given null as if given an empty list.
hashValues(Object arg01, Object arg02, [ Object arg03 = _hashEnd, Object arg04 = _hashEnd, Object arg05 = _hashEnd, Object arg06 = _hashEnd, Object arg07 = _hashEnd, Object arg08 = _hashEnd, Object arg09 = _hashEnd, Object arg10 = _hashEnd, Object arg11 = _hashEnd, Object arg12 = _hashEnd, Object arg13 = _hashEnd, Object arg14 = _hashEnd, Object arg15 = _hashEnd, Object arg16 = _hashEnd, Object arg17 = _hashEnd, Object arg18 = _hashEnd, Object arg19 = _hashEnd, Object arg20 = _hashEnd ]) int
Combine up to twenty objects' hash codes into one value. [...]
paintImage({Canvas canvas, Rect rect, Image image, ColorFilter colorFilter, BoxFit fit, FractionalOffset alignment, Rect centerSlice, ImageRepeat repeat: ImageRepeat.noRepeat }) → void
Paints an image into the given rectangle in the canvas. [...]

Enums

Axis
The two cardinal directions in two dimensions.
AxisDirection
A direction along either the horizontal or vertical Axis.
BlendMode
Algorithms to use when painting on the canvas. [...]
BlurStyle
Styles to use for blurs in MaskFilter objects.
BorderStyle
The style of line to draw for a BorderSide in a Border.
BoxFit
How a box should be inscribed into another box. [...]
BoxShape
The shape to use when rendering a BoxDecoration.
CrossAxisAlignment
How the children should be placed along the cross axis in a flex layout. [...]
DecorationPosition
Where to paint a box decoration.
FilterQuality
Quality levels for image filters. [...]
FlexFit
How the child is inscribed into the available space. [...]
FlutterLogoStyle
Possible ways to draw Flutter's logo.
FontStyle
Whether to slant the glyphs in the font
GrowthDirection
The direction in which a sliver's contents are ordered, relative to the scroll offset axis. [...]
HitTestBehavior
How to behave during hit tests.
ImageRepeat
How to paint any portions of a box not covered by an image.
MainAxisAlignment
How the children should be placed along the main axis in a flex layout. [...]
MainAxisSize
How much space should be occupied in the main axis. [...]
Overflow
Whether overflowing children should be clipped, or their overflow be visible.
PaintingStyle
Strategies for painting shapes and paths on a canvas. [...]
PathFillType
Determines the winding rule that decides how the interior of a Path is calculated. [...]
PerformanceOverlayOption
The options that control whether the performance overlay displays certain aspects of the compositor.
ScrollDirection
The direction of a scroll, relative to the positive scroll offset axis given by an AxisDirection and a GrowthDirection. [...]
StackFit
How to size the non-positioned children of a Stack. [...]
StrokeCap
Styles to use for line endings. [...]
TableCellVerticalAlignment
Vertical alignment options for cells in RenderTable objects. [...]
TextAlign
Whether to align text horizontally.
TextBaseline
A horizontal line used for aligning text.
TextDecorationStyle
The style in which to draw a text decoration
TextDirection
A direction in which text flows.
TextOverflow
How overflowing text should be handled.
TileMode
Defines what happens at the edge of the gradient. [...]
VertexMode
Defines how a list of points is interpreted when drawing a set of triangles. [...]
WrapAlignment
How Wrap should align objects. [...]
WrapCrossAlignment
Who Wrap should align children within a run in the cross axis.

Typedefs

CaretChangedHandler(Rect caretRect) → void
Signature for the callback that reports when the caret location changes. [...]
InformationCollector(StringBuffer information) → void
Signature for FlutterErrorDetails.informationCollector callback and other callbacks that collect information into a string buffer.
LayoutCallback(T constraints) → void
Signature for a function that is called during layout. [...]
PaintingContextCallback(PaintingContext context, Offset offset) → void
Signature for painting into a PaintingContext. [...]
PointerCancelEventListener(PointerCancelEvent event) → void
Signature for listening to PointerCancelEvent events. [...]
PointerDownEventListener(PointerDownEvent event) → void
Signature for listening to PointerDownEvent events. [...]
PointerMoveEventListener(PointerMoveEvent event) → void
Signature for listening to PointerMoveEvent events. [...]
PointerUpEventListener(PointerUpEvent event) → void
Signature for listening to PointerUpEvent events. [...]
RenderObjectVisitor(RenderObject child) → void
Signature for a function that is called for each RenderObject. [...]
SelectionChangedHandler(TextSelection selection, RenderEditable renderObject, bool longPress) → void
Signature for the callback that reports when the user changes the selection (including the cursor location). [...]
SemanticsAnnotator(SemanticsNode semantics) → void
Signature for functions returned by RenderObject.semanticsAnnotator. [...]
SemanticsNodeVisitor(SemanticsNode node) bool
Signature for a function that is called for each SemanticsNode. [...]
ShaderCallback(Rect bounds) Shader
Signature for a function that creates a Shader for a given Rect. [...]
ValueChanged(T value) → void
Signature for callbacks that report that an underlying value has changed. [...]
ValueGetter() → T
Signature for callbacks that are to report a value on demand. [...]
ValueSetter(T value) → void
Signature for callbacks that report that a value has been set. [...]
VoidCallback() → void
Signature of callbacks that have no arguments and return no data.

Exceptions / Errors

FlutterError
Error class used to report Flutter-specific assertion failures and contract violations.