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slider

compute_step​

def compute_step(difference: Decimal) -> Decimal

Compute what step should be used for the given domain difference.

The step is computed as: step = 10^(floor(log10(difference))) / 10

For cases where the step is a decimal (i.e. when the log10 is negative), the result is quantized to a fixed number of decimal places to avoid floating point imprecision.

Arguments:

  • difference: The domain difference (must be positive).

Returns:

The computed step.

Slider​

from dara.components.common.slider import Slider

class Slider(FormComponent)

Slider

A component to create a slider. The domain, ticks, stepping, rails and rail labels are controllable. The number of handles and their initial values are set via the number of values supplied. The value variable will update when handles are moved.

A simple Slider component with a single handle that tracks the selected value over a given range is created via:

from dara.core import Variable
from dara.components.common import Slider

value_var = Variable(0.5)

Slider(
    domain=[0.0, 1.0],
    value=value_var,
)

A more complex example with multiple handles, a set step size, specified ticks, a right hand rail and a track label is created via:

from dara.core import Variable
from dara.components.common import Slider

value_var = Variable([-3, 6, 8])

Slider(
    domain=[-10, 10],
    step=2,
    rail_from_start=False,
    rail_labels=['My Slider'],
    rail_to_end=True,
    ticks=[-9, -5, -1, 1, 5, 9],
    value=value_var,
)

Setting the disable_input_alternative to True removes the switch for changing the slider to a numerical input box:

from dara.core.definitions import Variable
from dara.components.common import Slider

value_var = Variable(0.5)

Slider(
    domain=[0.0, 1.0],
    value=value_var,
    disable_input_alternative=True,
)

Arguments:

  • domain: The range of the slider
  • onchange: Optional action to call on each slider update
  • step: The step size of the slider
  • rail_from_start: Boolean, if True the track is rendered from leftmost handle to the end
  • rail_labels: A label for the track
  • rail_to_end: Boolean, if True the track is rendered from rightmost handle to the end
  • thumb_labels: A list of labels for the slider's thumbs
  • ticks: List specifying the position of the ticks
  • value: A Variable instance recording the component's state; can be a single number for single-handle Slider, or an N-length array for a Slider with N handles
  • disable_input_alternative: Boolean, if True disable the rendering of the input alternative switch
  • id: the key to be used if this component is within a form

Attributes​

  • domain: List[float]
  • onchange: Optional[Action]
  • step: Optional[float]
  • rail_from_start: bool
  • rail_labels: Optional[List[str]]
  • rail_to_end: bool
  • thumb_labels: Optional[List[str]]
  • ticks: Optional[List[Union[float, int]]]
  • value: Optional[Union[Variable[Any], UrlVariable[Any]]]
  • disable_input_alternative: bool
  • id: Optional[str]