AnnotationWidget class

Framework widget that wraps custom annotations with automatic functionality.

This widget serves as the universal rendering layer for ALL annotation types, automatically providing:

  • Reactive positioning: Updates automatically based on annotation.visualPosition
  • Visibility control: Shows/hides based on annotation.isVisible
  • Selection feedback: Theme-consistent borders and highlights when selected
  • Hover feedback: Visual indication when annotation is being dragged over (highlighted)
  • Theme integration: Uses NodeFlowTheme for consistent styling across the editor
  • Gesture handling: Tap, double-tap, drag, and context menu events
  • Resize handles: Shown for annotations where Annotation.isResizable is true

Framework Integration

Custom annotation implementers only need to focus on their Annotation.buildWidget method. The AnnotationWidget handles all positioning, selection, theming, and interaction logic automatically.

The widget wraps the custom annotation content with:

  1. Observer for MobX reactivity
  2. Positioned for absolute canvas positioning
  3. GestureDetector and MouseRegion for interaction handling
  4. Selection/highlight borders using theme colors
  5. Visibility logic to hide when annotation.isVisible is false
  6. Resize handles when annotation is selected and resizable

Unified Annotation Handling

This widget handles ALL annotation types uniformly:

  • StickyAnnotation: Resizable sticky notes
  • GroupAnnotation: Resizable/non-resizable groups (based on behavior)
  • MarkerAnnotation: Non-resizable markers
  • Custom annotations: Any annotation implementing Annotation

Selection and highlight states are read directly from the annotation and controller, eliminating the need for specialized widgets per annotation type.

Example Usage

This widget is typically used internally by AnnotationLayer:

AnnotationWidget(
  annotation: stickyNote,
  controller: controller,
  onTap: () => controller.selectAnnotation(stickyNote.id),
)

See also:

Inheritance

Constructors

AnnotationWidget({Key? key, required Annotation annotation, required NodeFlowController controller, VoidCallback? onTap, VoidCallback? onDoubleTap, void onContextMenu(Offset globalPosition)?, VoidCallback? onMouseEnter, VoidCallback? onMouseLeave})
Creates an annotation widget.
const

Properties

annotation → Annotation
The annotation to render.
final
controller → NodeFlowController
Controller for drag handling and state queries.
final
hashCode → int
The hash code for this object.
no setterinherited
key → Key?
Controls how one widget replaces another widget in the tree.
finalinherited
onContextMenu → void Function(Offset globalPosition)?
Callback invoked when the annotation is right-clicked (context menu).
final
onDoubleTap → VoidCallback?
Callback invoked when the annotation is double-tapped.
final
onMouseEnter → VoidCallback?
Callback invoked when mouse enters the annotation.
final
onMouseLeave → VoidCallback?
Callback invoked when mouse leaves the annotation.
final
onTap → VoidCallback?
Callback invoked when the annotation is tapped.
final
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited

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