ScannerPreview class

Live camera preview with the detection outline, framing guide and grid composited on top.

Drop this anywhere in your own layout:

ScannerPreview(controller: controller)

The outline is interpolated every vsync inside an isolated RepaintBoundary, so a moving document never triggers a rebuild of the camera texture or of your surrounding UI.

Inheritance

Constructors

ScannerPreview({Key? key, required ScannerController controller, bool showOutline = true, bool showGuide = true, bool showGrid = true, bool enableTapToFocus = true, bool enableZoomGesture = true, WidgetBuilder? loadingBuilder, Widget errorBuilder(BuildContext context, String message)?, Widget permissionBuilder(BuildContext context, ScannerController controller)?})
const

Properties

controller ScannerController
final
enableTapToFocus bool
final
enableZoomGesture bool
final
errorBuilder Widget Function(BuildContext context, String message)?
Shown when the camera is unavailable. Receives the failure message.
final
hashCode int
The hash code for this object.
no setterinherited
key Key?
Controls how one widget replaces another widget in the tree.
finalinherited
loadingBuilder WidgetBuilder?
Shown while the camera is starting or suspended.
final
permissionBuilder Widget Function(BuildContext context, ScannerController controller)?
Shown when the camera permission is missing. Replace it to explain the situation in your own words and styling.
final
runtimeType Type
A representation of the runtime type of the object.
no setterinherited
showGrid bool
Draw the rule-of-thirds grid when the controller has it enabled.
final
showGuide bool
Draw the configured paper guide (A4 / Letter).
final
showOutline bool
Draw the detected document outline and auto-capture ring.
final

Methods

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