BackgroundPainter class - background_painter library

Constructors

BackgroundPainter({required BackgroundSpec spec, required Color surface, Rect? textSafeArea, Rect? toolbarExclusion, double patternFade = 1, bool reduceMotion = false, double? driftSeconds, BackgroundCache? cache})

Properties

cache → BackgroundCache: Shader / picture cache.
final
currentDriftSeconds → double: The drift time this paint uses (0 under Reduce Motion).
no setter
driftSeconds → double?: Drift time to paint at; null reads AmbientClock.instance.
final
hashCode → int: The hash code for this object.
no setterinherited
keyFaceDelegate → CustomPainter: Available on CustomPainter, provided by the LiveKeyFacePainterAccess extension
The renderer's painter behind a LiveKeyFacePainter (this painter otherwise).
no setter
patternFade → double: Extra pattern opacity, 0–1 (see SpecBackdrop.patternFade).
final
patternOpacity → double: Pattern ink opacity: BackgroundSpec.patternOpacityPermille when set, else the pattern colour's alpha; capped at maxPatternOpacity.
no setter
reduceMotion → bool: Freezes a drifting background at its first frame.
final
runtimeType → Type: A representation of the runtime type of the object.
no setterinherited
semanticsBuilder → SemanticsBuilderCallback?: Returns a function that builds semantic information for the picture drawn by this painter.
no setterinherited
spec → BackgroundSpec: What to paint.
final
surface → Color: The palette surface (not painted; see SpecBackdrop.surface).
final
textSafeArea → Rect?: Display text area to keep legible (null: none).
final
toolbarExclusion → Rect?: Toolbar chrome a scene keeps its art clear of (BackgroundScene.toolbarExclusion; null: none).
final

Methods

addListener(VoidCallback listener) → void: Register a closure to be notified when it is time to repaint.
inherited
hitTest(Offset position) → bool?: Called whenever a hit test is being performed on an object that is using this custom paint delegate.
inherited
noSuchMethod(Invocation invocation) → dynamic: Invoked when a nonexistent method or property is accessed.
inherited
paint(Canvas canvas, Size size) → void: Called whenever the object needs to paint. The given Canvas has its coordinate space configured such that the origin is at the top left of the box. The area of the box is the size of the size argument.
override
removeListener(VoidCallback listener) → void: Remove a previously registered closure from the list of closures that the object notifies when it is time to repaint.
inherited
shouldRebuildSemantics(covariant CustomPainter oldDelegate) → bool: Called whenever a new instance of the custom painter delegate class is provided to the RenderCustomPaint object, or any time that a new CustomPaint object is created with a new instance of the custom painter delegate class (which amounts to the same thing, because the latter is implemented in terms of the former).
inherited
shouldRepaint(covariant BackgroundPainter oldDelegate) → bool: Called whenever a new instance of the custom painter delegate class is provided to the RenderCustomPaint object, or any time that a new CustomPaint object is created with a new instance of the custom painter delegate class (which amounts to the same thing, because the latter is implemented in terms of the former).
override
toString() → String: A string representation of this object.
inherited

Operators

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

Constants

maxPatternOpacity → const double: Highest pattern ink opacity (patterns stay texture, not content).
safeFade → const double: Height of the fade below textSafeArea, dp.
tileScale → const double: Pattern tiles are rasterised at this scale (sharp up to 3× screens).