ResponsiveImage class
A responsive image widget that displays different images based on the current screen type, optimizing memory usage and visual quality.
Performance Design
- Only one ImageProvider is resolved per build (no unused images loaded)
- Uses Image widget with
gaplessPlayback: truefor smooth transitions - Optional
cacheWidth/cacheHeightvia autoOptimize for memory savings - Fallback chain: desktop → tablet → mobile ensures no null images
Example
ResponsiveImage(
mobile: AssetImage('assets/banner_sm.webp'),
tablet: AssetImage('assets/banner_md.webp'),
desktop: AssetImage('assets/banner_lg.webp'),
fit: BoxFit.cover,
height: 200.s,
)
- Inheritance
-
- Object
- DiagnosticableTree
- Widget
- StatelessWidget
- ResponsiveImage
Constructors
-
ResponsiveImage({Key? key, required ImageProvider<
Object> mobile, ImageProvider<Object> ? tablet, ImageProvider<Object> ? desktop, BoxFit fit = BoxFit.cover, double? width, double? height, Alignment alignment = Alignment.center, Widget? placeholder, Widget? errorWidget, bool autoOptimize = false, BorderRadius? borderRadius, Color? color, BlendMode? colorBlendMode, String? semanticLabel}) -
Creates a ResponsiveImage.
const
Properties
- alignment → Alignment
-
Alignment within the container. Default: Alignment.center.
final
- autoOptimize → bool
-
Whether to automatically resize the decoded image to match the
display size, reducing memory usage. Default:
false.final - borderRadius → BorderRadius?
-
Border radius for the image. If null, no clipping.
final
- color → Color?
-
Color filter to apply on the image (e.g., for overlays).
final
- colorBlendMode → BlendMode?
-
Blend mode for color. Default: BlendMode.srcIn.
final
-
desktop
→ ImageProvider<
Object> ? -
Optional image for desktop/large desktop. Falls back to tablet → mobile.
final
- errorWidget → Widget?
-
Widget to show if the image fails to load.
final
- fit → BoxFit
-
How to inscribe the image into the space. Default: BoxFit.cover.
final
- hashCode → int
-
The hash code for this object.
no setterinherited
- height → double?
-
Optional fixed height for the image container.
final
- key → Key?
-
Controls how one widget replaces another widget in the tree.
finalinherited
-
mobile
→ ImageProvider<
Object> -
The image to display on mobile/watch screens. Required as the fallback.
final
- placeholder → Widget?
-
Widget to show while the image is loading.
final
- runtimeType → Type
-
A representation of the runtime type of the object.
no setterinherited
- semanticLabel → String?
-
Semantic label for accessibility.
final
-
tablet
→ ImageProvider<
Object> ? -
Optional image for tablet screens. Falls back to mobile.
final
- width → double?
-
Optional fixed width for the image container.
final
Methods
-
build(
BuildContext context) → Widget -
Describes the part of the user interface represented by this widget.
override
-
createElement(
) → StatelessElement -
Creates a StatelessElement to manage this widget's location in the tree.
inherited
-
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.
inherited
-
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, int wrapWidth = 65}) → 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