painting library

Classes

Accumulator: Mutable wrapper of an integer that can be passed by reference to track a value across a recursive stack.
Alignment: A point within a rectangle.
AlignmentDirectional: An offset that's expressed as a fraction of a Size, but whose horizontal component is dependent on the writing direction.
AlignmentGeometry: Base class for Alignment that allows for text-direction aware resolution.
AssetBundleImageKey: Key for the image obtained by an AssetImage or ExactAssetImage.
AssetBundleImageProvider: A subclass of ImageProvider that knows about AssetBundles.
AssetImage: Fetches an image from an AssetBundle, having determined the exact image to use based on the context.
AutomaticNotchedShape: A NotchedShape created from ShapeBorders.
BeveledRectangleBorder: A rectangular border with flattened or "beveled" corners.
Border: A border of a box, comprised of four sides: top, right, bottom, left.
BorderDirectional: A border of a box, comprised of four sides, the lateral sides of which flip over based on the reading direction.
BorderRadius: An immutable set of radii for each corner of a rectangle.
BorderRadiusDirectional: An immutable set of radii for each corner of a rectangle, but with the corners specified in a manner dependent on the writing direction.
BorderRadiusGeometry: Base class for BorderRadius that allows for text-direction aware resolution.
BorderSide: A side of a border of a box.
BoxBorder: Base class for box borders that can paint as rectangles, circles, or rounded rectangles.
BoxDecoration: An immutable description of how to paint a box.
BoxPainter: A stateful class that can paint a particular Decoration.
BoxShadow: A shadow cast by a box.
Canvas: An interface for recording graphical operations.
CircleBorder: A border that fits a circle within the available space.
CircularNotchedRectangle: A rectangle with a smooth circular notch.
ClipContext: Clip utilities used by PaintingContext.
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.
ColorProperty: DiagnosticsProperty that has an Color as value.
ColorSwatch<T>: A color that has a small table of related colors called a "swatch".
ContinuousRectangleBorder: A rectangular border with smooth continuous transitions between the straight sides and the rounded corners.
Decoration: A description of a box decoration (a decoration applied to a Rect).
DecorationImage: An image for a box decoration.
DecorationImagePainter: The painter for a DecorationImage.
EdgeInsets: An immutable set of offsets in each of the four cardinal directions.
EdgeInsetsDirectional: An immutable set of offsets in each of the four cardinal directions, but whose horizontal components are dependent on the writing direction.
EdgeInsetsGeometry: Base class for EdgeInsets that allows for text-direction aware resolution.
ExactAssetImage: Fetches an image from an AssetBundle, associating it with the given scale.
FileImage: Decodes the given File object as an image, associating it with the given scale.
FittedSizes: The pair of sizes returned by applyBoxFit.
FlutterLogoDecoration: An immutable description of how to paint Flutter's logo.
FontFeature: A feature tag and value that affect the selection of glyphs in a font.
FontVariation: An axis tag and value that can be used to customize variable fonts.
FontWeight: The thickness of the glyphs used to draw the text.
FractionalOffset: An offset that's expressed as a fraction of a Size.
GlyphInfo: The measurements of a character (or a sequence of visually connected characters) within a paragraph.
Gradient: A 2D gradient.
GradientRotation: A GradientTransform that rotates the gradient around the center-point of its bounding box.
GradientTransform: Base class for transforming gradient shaders without applying the same transform to the entire canvas.
HSLColor: A color represented using alpha, hue, saturation, and lightness.
HSVColor: A color represented using alpha, hue, saturation, and value.
ImageCache: Class for caching images.
ImageCacheStatus: Information about how the ImageCache is tracking an image.
ImageChunkEvent: An immutable notification of image bytes that have been incrementally loaded.
ImageConfiguration: Configuration information passed to the ImageProvider.resolve method to select a specific image.
ImageInfo: A dart:ui.Image object with its corresponding scale.
ImageProvider<T extends Object>: Identifies an image without committing to the precise final asset. This allows a set of images to be identified and for the precise image to later be resolved based on the environment, e.g. the device pixel ratio.
ImageShader: A shader (as used by Paint.shader) that tiles an image.
ImageSizeInfo: Tracks the bytes used by a dart:ui.Image compared to the bytes needed to paint that image without scaling it.
ImageStream: A handle to an image resource.
ImageStreamCompleter: Base class for those that manage the loading of dart:ui.Image objects for ImageStreams.
ImageStreamCompleterHandle: An opaque handle that keeps an ImageStreamCompleter alive even if it has lost its last listener.
ImageStreamListener: Interface for receiving notifications about the loading of an image.
InlineSpan: An immutable span of inline content which forms part of a paragraph.
InlineSpanSemanticsInformation: The textual and semantic label information for an InlineSpan.
LinearBorder: An OutlinedBorder like BoxBorder that allows one to define a rectangular (box) border in terms of zero to four LinearBorderEdges, each of which is rendered as a single line.
LinearBorderEdge: Defines the relative size and alignment of one edge.
LinearGradient: A 2D linear gradient.
LineMetrics: LineMetrics stores the measurements and statistics of a single line in the paragraph.
Locale: An identifier used to select a user's language and formatting preferences.
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.
MatrixUtils: Utility functions for working with matrices.
MemoryImage: Decodes the given Uint8List buffer as an image, associating it with the given scale.
MultiFrameImageStreamCompleter: Manages the decoding and scheduling of image frames.
NetworkImage: Fetches the given URL from the network, associating it with the given scale.
NotchedShape: A shape with a notch in its outline.
Offset: An immutable 2D floating-point offset.
OneFrameImageStreamCompleter: Manages the loading of dart:ui.Image objects for static ImageStreams (those with only one frame).
OutlinedBorder: A ShapeBorder that draws an outline with the width and color specified by side.
OvalBorder: A border that fits an elliptical shape.
Paint: A description of the style to use when drawing on a Canvas.
Path: A complex, one-dimensional subset of a plane.
PlaceholderDimensions: Holds the Size and baseline required to represent the dimensions of a placeholder in text.
PlaceholderSpan: An immutable placeholder that is embedded inline within text.
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.
ResizeImage: Instructs Flutter to decode the image at the specified dimensions instead of at its native size.
ResizeImageKey: Key used internally by ResizeImage.
RoundedRectangleBorder: A rectangular border with rounded corners.
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.
Shader: Base class for objects such as Gradient and ImageShader which correspond to shaders as used by Paint.shader.
ShaderWarmUp: Interface for drawing an image to warm up Skia shader compilations.
Shadow: A single shadow.
ShapeBorder: Base class for shape outlines.
ShapeDecoration: An immutable description of how to paint an arbitrary shape.
Size: Holds a 2D floating-point size.
StadiumBorder: A border that fits a stadium-shaped border (a box with semicircles on the ends) within the rectangle of the widget it is applied to.
StarBorder: A border that fits a star or polygon-shaped border within the rectangle of the widget it is applied to.
StrutStyle: Defines the strut, which sets the minimum height a line can be relative to the baseline.
SweepGradient: A 2D sweep gradient.
TextAlignVertical: The vertical alignment of text within an input box.
TextBox: A rectangle enclosing a run of text.
TextDecoration: A linear decoration to draw near the text.
TextHeightBehavior: Defines how to apply TextStyle.height over and under text.
TextPainter: An object that paints a TextSpan tree into a Canvas.
TextPosition: A position in a string of text.
TextRange: A range of characters in a string of text.
TextScaler: A class that describes how textual contents should be scaled for better readability.
TextSelection: A range of text that represents a selection.
TextSpan: An immutable span of text.
TextStyle: An immutable style describing how to format and paint text.
TransformProperty: Property which handles Matrix4 that represent transforms.
WordBoundary: A TextBoundary subclass for locating word breaks.

Enums

Axis: The two cardinal directions in two dimensions.
AxisDirection: A direction along either the horizontal or vertical Axis in which the origin, or zero position, is determined.
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 Border or BoxDecoration.
Clip: Different ways to clip a widget's content.
FilterQuality: Quality levels for image sampling in ImageFilter and Shader objects that sample images and for Canvas operations that render images.
FlutterLogoStyle: Possible ways to draw Flutter's logo.
FontStyle: Whether to use the italic type variation of glyphs in the font.
ImageRepeat: How to paint any portions of a box not covered by an image.
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.
PathOperation: Strategies for combining paths.
PlaceholderAlignment: Where to vertically align the placeholder relative to the surrounding text.
RenderComparison: The description of the difference between two objects, in the context of how it will affect the rendering.
ResizeImagePolicy: Configures the behavior for ResizeImage.
StrokeCap: Styles to use for line endings.
StrokeJoin: Styles to use for line segment joins.
TextAffinity: A way to disambiguate a TextPosition when its offset could match two different locations in the rendered string.
TextAlign: Whether and how 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.
TextLeadingDistribution: How the "leading" is distributed over and under the text.
TextOverflow: How overflowing text should be handled.
TextWidthBasis: The different ways of measuring the width of one or more lines of text.
TileMode: Defines what happens at the edge of a gradient or the sampling of a source image in an ImageFilter.
VertexMode: Defines how a list of points is interpreted when drawing a set of triangles.
VerticalDirection: A direction in which boxes flow vertically.

Mixins

PaintingBinding: Binding for the painting library.

Constants

kDefaultFontSize → const double: The default font size if none is specified.
kTextHeightNone → const double: A TextStyle.height value that indicates the text span should take the height defined by the font, which may not be exactly the height of TextStyle.fontSize.

Properties

debugCaptureShaderWarmUpImage ↔ ShaderWarmUpImageCallback: Called by ShaderWarmUp.execute immediately after it creates an Image.
getter/setter pair
debugCaptureShaderWarmUpPicture ↔ ShaderWarmUpPictureCallback: Called by ShaderWarmUp.execute immediately after it creates a Picture.
getter/setter pair
debugDisableShadows ↔ bool: Whether to replace all shadows with solid color blocks.
getter/setter pair
debugImageOverheadAllowance ↔ int: The number of bytes an image must use before it triggers inversion when debugInvertOversizedImages is true.
getter/setter pair
debugInvertOversizedImages ↔ bool: If true, the framework will color invert and horizontally flip images that have been decoded to a size taking at least debugImageOverheadAllowance bytes more than necessary.
getter/setter pair
debugNetworkImageHttpClientProvider ↔ HttpClientProvider?: Provider from which NetworkImage will get its HttpClient in debug builds.
getter/setter pair
debugOnPaintImage ↔ PaintImageCallback?: If not null, called when the framework is about to paint an Image to a Canvas with an ImageSizeInfo that contains the decoded size of the image as well as its output size.
getter/setter pair
imageCache → ImageCache: The singleton that implements the Flutter framework's image cache.
no setter

Functions

applyBoxFit(BoxFit fit, Size inputSize, Size outputSize) → FittedSizes: Apply a BoxFit value.
axisDirectionIsReversed(AxisDirection axisDirection) → bool: Returns whether traveling 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.
combineSemanticsInfo(List<InlineSpanSemanticsInformation> infoList) → List<InlineSpanSemanticsInformation>: Combines _semanticsInfo entries where permissible.
debugAssertAllPaintingVarsUnset(String reason, {bool debugDisableShadowsOverride = false}) → bool: Returns true if none of the painting 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 TransformProperty.
debugFlushLastFrameImageSizeInfo() → void: Flushes inter-frame tracking of image size information from paintImage.
decodeImageFromList(Uint8List bytes) → Future<Image>: Creates an image from a list of bytes.
flipAxis(Axis direction) → Axis: Returns the opposite of the given Axis.
flipAxisDirection(AxisDirection axisDirection) → AxisDirection: Returns the opposite of the given AxisDirection.
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.
lerpFontVariations(List<FontVariation>? a, List<FontVariation>? b, double t) → List<FontVariation>?: Interpolate between two lists of FontVariation objects.
paintBorder(Canvas canvas, Rect rect, {BorderSide top = BorderSide.none, BorderSide right = BorderSide.none, BorderSide bottom = BorderSide.none, BorderSide left = BorderSide.none}) → void: Paints a border around the given rectangle on the canvas.
paintImage({required Canvas canvas, required Rect rect, required Image image, String? debugImageLabel, double scale = 1.0, double opacity = 1.0, ColorFilter? colorFilter, BoxFit? fit, Alignment alignment = Alignment.center, Rect? centerSlice, ImageRepeat repeat = ImageRepeat.noRepeat, bool flipHorizontally = false, bool invertColors = false, FilterQuality filterQuality = FilterQuality.medium, bool isAntiAlias = false, BlendMode blendMode = BlendMode.srcOver}) → void: Paints an image into the given rectangle on the canvas.
paintZigZag(Canvas canvas, Paint paint, Offset start, Offset end, int zigs, double width) → void: Draw a line between two points, which cuts diagonally back and forth across the line that connects the two points.
positionDependentBox({required Size size, required Size childSize, required Offset target, required bool preferBelow, double verticalOffset = 0.0, double margin = 10.0}) → Offset: Position a child box within a container box, either above or below a target point.
textDirectionToAxisDirection(TextDirection textDirection) → AxisDirection: Returns the AxisDirection in which reading occurs in the given TextDirection.

Typedefs

DecoderBufferCallback = Future<Codec> Function(ImmutableBuffer buffer, {bool allowUpscaling, int? cacheHeight, int? cacheWidth}): Performs the decode process for use in ImageProvider.loadBuffer.
HttpClientProvider = HttpClient Function(): Signature for a method that returns an HttpClient.
ImageChunkListener = void Function(ImageChunkEvent event): Signature for listening to ImageChunkEvent events.
ImageDecoderCallback = Future<Codec> Function(ImmutableBuffer buffer, {TargetImageSizeCallback? getTargetSize}): Performs the decode process for use in ImageProvider.loadImage.
ImageErrorListener = void Function(Object exception, StackTrace? stackTrace): Signature for reporting errors when resolving images.
ImageListener = void Function(ImageInfo image, bool synchronousCall): Signature for callbacks reporting that an image is available.
InlineSpanVisitor = bool Function(InlineSpan span): Called on each span as InlineSpan.visitChildren walks the InlineSpan tree.
PaintImageCallback = void Function(ImageSizeInfo info): Called when the framework is about to paint an Image to a Canvas with an ImageSizeInfo that contains the decoded size of the image as well as its output size.
ShaderWarmUpImageCallback = bool Function(Image image): The signature of debugCaptureShaderWarmUpImage.
ShaderWarmUpPictureCallback = bool Function(Picture picture): The signature of debugCaptureShaderWarmUpPicture.
VoidCallback = void Function(): Signature of callbacks that have no arguments and return no data.

Exceptions / Errors

NetworkImageLoadException: The exception thrown when the HTTP request to load a network image fails.

Classes

Enums

Mixins

Constants

Properties

Functions

Typedefs

Exceptions / Errors

Flutter package

painting library