ImageExt class

A widget that displays an image.

Several constructors are provided for the various ways that an image can be specified:

The following image formats are supported: JPEG, PNG, GIF, Animated GIF, WebP, Animated WebP, BMP, and WBMP. Additional formats may be supported by the underlying platform. Flutter will attempt to call platform API to decode unrecognized formats, and if the platform API supports decoding the image Flutter will be able to render it.

To automatically perform pixel-density-aware asset resolution, specify the image using an AssetImage and make sure that a MaterialApp, WidgetsApp, or MediaQuery widget exists above the Image widget in the widget tree.

The image is painted using paintImage, which describes the meanings of the various fields on this class in more detail.

{@tool snippet} The default constructor can be used with any ImageProvider, such as a NetworkImage, to display an image from the internet.

An image of an owl displayed by the image widget

const Image(
  image: NetworkImage('https://flutter.github.io/assets-for-api-docs/assets/widgets/owl.jpg'),
)

{@end-tool}

{@tool snippet} The Image Widget also provides several constructors to display different types of images for convenience. In this example, use the Image.network constructor to display an image from the internet.

An image of an owl displayed by the image widget using the shortcut constructor

Image.network('https://flutter.github.io/assets-for-api-docs/assets/widgets/owl-2.jpg')

{@end-tool}

The Image.asset, Image.network, Image.file, and Image.memory constructors allow a custom decode size to be specified through cacheWidth and cacheHeight parameters. The engine will decode the image to the specified size, which is primarily intended to reduce the memory usage of ImageCache.

In the case where a network image is used on the Web platform, the cacheWidth and cacheHeight parameters are ignored as the Web engine delegates image decoding of network images to the Web, which does not support custom decode sizes.

See also:

Inheritance

Constructors

ImageExt({Key? key, required ImageProvider<Object> image, CustomImageBuilder? imageBuilder, ImageFrameBuilder? frameBuilder, ImageLoadingBuilder? loadingBuilder, ImageErrorWidgetBuilder? errorBuilder, String? semanticLabel, bool excludeFromSemantics = false, double? width, double? height, Color? color, Animation<double>? opacity, BlendMode? colorBlendMode, BoxFit? fit, AlignmentGeometry alignment = Alignment.center, ImageRepeat repeat = ImageRepeat.noRepeat, Rect? centerSlice, bool matchTextDirection = false, bool gaplessPlayback = false, bool isAntiAlias = false, bool scrollAwareEnable = false, FilterQuality filterQuality = FilterQuality.low})
Creates a widget that displays an image.
const

Properties

alignment AlignmentGeometry
How to align the image within its bounds.
final
centerSlice Rect?
The center slice for a nine-patch image.
final
color Color?
If non-null, this color is blended with each image pixel using colorBlendMode.
final
colorBlendMode BlendMode?
Used to combine color with this image.
final
errorBuilder ImageErrorWidgetBuilder?
A builder function that is called if an error occurs during image loading.
final
excludeFromSemantics bool
Whether to exclude this image from semantics.
final
filterQuality FilterQuality
The rendering quality of the image.
final
fit BoxFit?
How to inscribe the image into the space allocated during layout.
final
frameBuilder ImageFrameBuilder?
A builder function responsible for creating the widget that represents this image.
final
gaplessPlayback bool
Whether to continue showing the old image (true), or briefly show nothing (false), when the image provider changes. The default value is false.
final
hashCode int
The hash code for this object.
no setterinherited
height double?
If non-null, require the image to have this height.
final
image ImageProvider<Object>
The image to display.
final
imageBuilder CustomImageBuilder?
final
isAntiAlias bool
Whether to paint the image with anti-aliasing.
final
key Key?
Controls how one widget replaces another widget in the tree.
finalinherited
loadingBuilder ImageLoadingBuilder?
A builder that specifies the widget to display to the user while an image is still loading.
final
matchTextDirection bool
Whether to paint the image in the direction of the TextDirection.
final
opacity Animation<double>?
If non-null, the value from the Animation is multiplied with the opacity of each image pixel before painting onto the canvas.
final
repeat ImageRepeat
How to paint any portions of the layout bounds not covered by the image.
final
runtimeType Type
A representation of the runtime type of the object.
no setterinherited
scrollAwareEnable bool
Whether to avoid loading images when rapidly scrolling.
final
semanticLabel String?
A Semantic description of the image.
final
width double?
If non-null, require the image to have this width.
final

Methods

createElement() StatefulElement
Creates a StatefulElement to manage this widget's location in the tree.
inherited
createState() State<ImageExt>
Creates the mutable state for this widget at a given location in the tree.
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
noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
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}) 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 widget.
inherited

Operators

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