LaunchPreviewCard class

A card widget that displays a rich preview for a given URL.

Fetches OpenGraph / Twitter Card metadata to provide a visual summary before the user taps to launch. Results are cached in memory for _PreviewData._cacheTtl to avoid redundant network requests when the same URL appears more than once in a list.

Why previous fetches silently failed on most production sites: Sites like Instagram, LinkedIn, and many CDNs return an empty body or a bot-detection page when the request carries no User-Agent. This widget now sends a standard browser User-Agent and follows up to one redirect, which resolves the majority of silent failures without requiring an external metadata proxy service.

Inheritance

Constructors

LaunchPreviewCard({Key? key, required String url, LaunchPreviewStyle? style, VoidCallback? onTap})
Creates a LaunchPreviewCard.
const

Properties

hashCode → int
The hash code for this object.
no setterinherited
key → Key?
Controls how one widget replaces another widget in the tree.
finalinherited
onTap → VoidCallback?
Callback executed when the card is tapped.
final
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited
style → LaunchPreviewStyle?
Styling for the card.
final
url → String
The URL to fetch metadata from and launch.
final

Methods

createElement() → StatefulElement
Creates a StatefulElement to manage this widget's location in the tree.
inherited
createState() → State<LaunchPreviewCard>
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.
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