LabelContainer class

Container of one label anywhere on the chart, in Labels, Axis, Titles, etc.

The layoutSize is exactly that of by the contained layed out _textPainter (this LabelContainer has no margins, padding, or additional content in addition to the [_textPainter).

However, if this object is tilted, as specified by _labelTiltMatrix, the layoutSize is determined by the rotated layed out _textPainter. The math and layoutSize of this tilt is provided by _tiltedLabelEnvelope.

Most members are mutable so that clients can experiment with different ways to set text style, until the label fits a predefined allowed size.

Notes:

  • Instances manage the text to be presented as label, and create a member _textPainter, instance of widgets.TextPainter from the label. The contained _textPainter is used for all layout and painting.
  • All methods (and constructor) of this class always call _textPainter.layout immediately after a change. Consequently, there is no need to check for a "needs layout" method - the underlying _textPainter is always layed out, ready to be painted.
Implementers

Constructors

LabelContainer({required String label, required double labelMaxWidth, required Matrix2 labelTiltMatrix, required LabelStyle labelStyle})
Constructs an instance for a label, it's text style, and label's maximum width.

Properties

enableSkipOnDistressedSize ↔ bool
If size constraints imposed by parent are too tight, some internal calculations of sizes may lead to negative values, making painting of this container not possible.
getter/setter pairinherited
hashCode → int
The hash code for this object.
no setterinherited
isDistressed ↔ bool
getter/setter pairinherited
layoutSize ↔ Size
Manages the layout size during the layout process in layout. Should be only mentioned in this class, not super
getter/setter pairinherited
offset ↔ Offset
Current absolute offset, set by parent (and it's parent etc, to root).
getter/setter pairinherited
offsetOfPotentiallyRotatedLabel ↔ Offset
Offset of this LabelContainer's label, created by the _textPainter.
getter/setter pair
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited
skipByParent ↔ bool
skipByParent instructs the parent container that this container should not be painted or layed out - as if it collapsed to zero size.
getter/setter pairinherited
tiltedLabelEnvelopeTopLeft → Offset
Position where paint starts painting the label, expressed in the coordinate system in which this _tiltedLabelEnvelope.envelopeRect topLeft (NOT the _tiltedLabelEnvelope.topLeft) is at the origin.
no setter
tiltMatrix → Matrix2
Provides access to tiltMatrix for extension's paint methods.
no setterinherited

Methods

applyParentOffset(Offset offset) → void
Calls super method, then adds the passed offset to the locally-kept slot offsetOfPotentiallyRotatedLabel.
applyParentTiltMatrix(Matrix2 tiltMatrix) → void
Tilt may apply to the whole container. todo-2 unused? move to base class? similar to offset?
inherited
layout(LayoutExpansion parentLayoutExpansion) → void
Lays out this LabelContainer.
noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
paint(Canvas canvas) → void
Implementor of method in superclass Container.
toString() → String
A string representation of this object.
inherited

Operators

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