LabelInfo class

The LabelInfo is a holder for one label, it's numeric value and the displayed label.

There are four values each LabelInfo manages:

  • The _rawDataValue : The value of dependent (y) variable in data, given by the YLabelsCreatorAndPositioner._mergedLabelYsIntervalWithDataYsEnvelope.
    • This value is not-scaled && not-transformed.
    • This value is in the interval extended from the interval of minimum and maximum y in data to the interval of the displayed labels. The reason is the chart may show axis lines and labels beyond the strict interval between minimum and maximum y in data.
    • This value is created in the generative constructor's LabelInfo initializer list from the transformedDataValue.
  • The _dataValue : The _rawDataValue after transformation by the DataContainerOptions.yTransform function.
    • This value is not-scaled && transformed
    • This value is same as _rawDataValue if the DataContainerOptions.yTransform is an identity (this is the default behavior). See lib/chart/options.dart.
    • This value is passed in the primary generative constructor LabelInfo.
  • The _axisValue : Equals to the scaled && transformed dataValue, in other words 
     _axisValue = parentYScaler.scaleY(value: transformedDataValue.toDouble());
    It is created as scaled _dataValue, in the PointsColumns where the scaling is from the Y data and labels envelop to the Y axis envelop.
    • This value is transformed and scaled.
    • This value is obtained as follows 
         _axisValue = parentYScaler.scaleY(value: transformedDataValue.toDouble());
   // which does
   return scaleValue(
       value: value.toDouble(),
       fromDomainMin: mergedLabelYsIntervalWithDataYsEnvelop.min.toDouble(),
       fromDomainMax: mergedLabelYsIntervalWithDataYsEnvelop.max.toDouble(),
       toDomainMin: _axisYMin,
       toDomainMax: _axisYMax);
    • The _formattedLabel : The formatted String-value of _rawDataValue.

Note: The **scaled && not-transformed ** value is not maintained.

Note: Data displayed inside the chart use transformed data values, displayed labels show raw data values.

Constructors

LabelInfo({required num dataValue, required YLabelsCreatorAndPositioner parentYScaler})
Constructs from value at the label, using scaler which keeps dataRange and axisRange (min, max).

Properties

axisValue → num
no setter
formattedLabel → String
no setter
hashCode → int
The hash code for this object.
no setterinherited
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited

Methods

noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
toString() → String
A string representation of this object.
override

Operators

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