Slider constructor

const Slider(
  1. {Key key,
  2. @required double value,
  3. @required ValueChanged<double> onChanged,
  4. ValueChanged<double> onChangeStart,
  5. ValueChanged<double> onChangeEnd,
  6. double min: 0.0,
  7. double max: 1.0,
  8. int divisions,
  9. String label,
  10. Color activeColor,
  11. Color inactiveColor,
  12. SemanticFormatterCallback semanticFormatterCallback}
)

Creates a Material Design slider.

The slider itself does not maintain any state. Instead, when the state of the slider changes, the widget calls the onChanged callback. Most widgets that use a slider will listen for the onChanged callback and rebuild the slider with a new value to update the visual appearance of the slider.

  • value determines currently selected value for this slider.
  • onChanged is called while the user is selecting a new value for the slider.
  • onChangeStart is called when the user starts to select a new value for the slider.
  • onChangeEnd is called when the user is done selecting a new value for the slider.

You can override some of the colors with the activeColor and inactiveColor properties, although more fine-grained control of the appearance is achieved using a SliderThemeData.

Implementation

const Slider({
  Key key,
  @required this.value,
  @required this.onChanged,
  this.onChangeStart,
  this.onChangeEnd,
  this.min = 0.0,
  this.max = 1.0,
  this.divisions,
  this.label,
  this.activeColor,
  this.inactiveColor,
  this.semanticFormatterCallback,
}) : _sliderType = _SliderType.material,
     assert(value != null),
     assert(min != null),
     assert(max != null),
     assert(min <= max),
     assert(value >= min && value <= max),
     assert(divisions == null || divisions > 0),
     super(key: key);