painting library
The Flutter painting library.
To use, import package:flutter/painting.dart.
This library includes a variety of classes that wrap the Flutter engine's painting API for more specialized purposes, such as painting scaled images, interpolating between shadows, painting borders around boxes, etc.
In particular:
- Use the TextPainter class for painting text.
- Use Decoration (and more concretely BoxDecoration) for painting boxes.
Classes
- 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. [...]
- 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 and
TestRecordingPaintingContext. - 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<
T> - A color that has a small table of related colors called a "swatch". [...]
- 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.
- FontWeight
- The thickness of the glyphs used to draw the text
- FractionalOffset
- An offset that's expressed as a fraction of a Size. [...]
- Gradient
- A 2D gradient. [...]
- HSLColor
- A color represented using alpha, hue, saturation, and lightness. [...]
- HSVColor
- A color represented using alpha, hue, saturation, and value. [...]
- ImageCache
- Class for the imageCache object. [...]
- 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> - 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.
- ImageStream
- A handle to an image resource. [...]
- ImageStreamCompleter
- Base class for those that manage the loading of dart:ui.Image objects for ImageStreams. [...]
- LinearGradient
- A 2D linear gradient. [...]
- 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).
- Paint
- A description of the style to use when drawing on a Canvas. [...]
- Path
- A complex, one-dimensional subset of a plane. [...]
- 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. [...]
- 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.
- 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. [...]
- SweepGradient
- A 2D sweep gradient. [...]
- TextBox
- A rectangle enclosing a run of text. [...]
- TextDecoration
- A linear decoration to draw near the text.
- TextPainter
- An object that paints a TextSpan tree into a Canvas. [...]
- TextPosition
- A visual position in a string of text.
- TextRange
- A range of characters in a string of text.
- TextSelection
- A range of text that represents a selection.
- TextSpan
- An immutable span of text. [...]
- TextStyle
- An immutable style in which paint text. [...]
- TransformProperty
- Property which handles Matrix4 that represent transforms.
Mixins
- PaintingBinding
- Binding for the painting library. [...]
Properties
- debugDisableShadows ↔ bool
-
Whether to replace all shadows with solid color blocks. [...]
read / write
- imageCache → ImageCache
-
The singleton that implements the Flutter framework's image cache. [...]
read-only
Functions
-
applyBoxFit(
BoxFit fit, Size inputSize, Size outputSize) → FittedSizes - Apply a BoxFit value. [...]
-
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. [...]
-
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. [...]
-
decodeImageFromList(
Uint8List list) → 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. [...]
-
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(
{Canvas canvas, Rect rect, Image image, double scale: 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.low }) → 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(
{Size size, Size childSize, Offset target, 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. [...]
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 Border or BoxDecoration. [...]
- Clip
- Different ways to clip a widget's content.
- FilterQuality
- Quality levels for image filters. [...]
- FlutterLogoStyle
- Possible ways to draw Flutter's logo.
- FontStyle
- Whether to slant the 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. [...]
- RenderComparison
- The description of the difference between two objects, in the context of how it will affect the rendering. [...]
- StrokeCap
- Styles to use for line endings. [...]
- StrokeJoin
- Styles to use for line segment joins. [...]
- TextAffinity
- Whether a TextPosition is visually upstream or downstream of its offset. [...]
- 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. [...]
- 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. [...]
- VerticalDirection
- A direction in which boxes flow vertically. [...]
Typedefs
-
ImageErrorListener(
dynamic exception, StackTrace stackTrace) → void - Signature for reporting errors when resolving images. [...]
-
ImageListener(
ImageInfo image, bool synchronousCall) → void - Signature for callbacks reporting that an image is available. [...]
-
VoidCallback(
) → void - Signature of callbacks that have no arguments and return no data.