Source code for branchpro.apps._sliders

#
# Sliders Class
#
# This file is part of BRANCHPRO
# (https://github.com/SABS-R3-Epidemiology/branchpro.git) which is released
# under the BSD 3-clause license. See accompanying LICENSE.md for copyright
# notice and full license details.
#

import dash_daq as daq
from dash import html

import numpy as np




class _SliderComponent():
    """_SliderComponent Class
    Stores slider information for sliders in branchpro Dash app.
    In this class we keep track of both the figure and the sliders determined
    by the data figure.
    """
    def __init__(self):
        self._sliders = []
        self._slider_ids = []



    def add_slider(
            self, label, new_id, init_val, min_val, max_val, step_size,
            as_integer=False, invisible=False):
        """
        Creates a new slider with label for the Dash app plot.

        Parameters
        ----------
        label
            Title text shown above slider.
        new_id
            ID of slider (internal, not shown in app).
        init_val
            Initial slider value (default position).
        min_val
            Minimum (leftmost) slider value.
        max_val
            Maximum (rightmost) slider value.
        step_size
            Incremement between slider values.
        as_integer
            (boolean) display decimals or not for the marks of sliders.
        invisible
            (boolean) hides slider object.
        """
        mark_list = np.arange(
                                start=min_val,
                                stop=max_val+step_size,
                                step=step_size,
                                dtype=np.float64
                                )
        if (mark_list.size > 10):
            mark_list = np.linspace(
                                        start=min_val,
                                        stop=max_val,
                                        num=10,
                                        dtype=np.float64
                                        )

        mark_list = np.round(mark_list, decimals=0 if as_integer else 2)

        keys = [int(r) if r.is_integer() else r for r in mark_list]
        if as_integer:
            locks = ['{:.0f}'.format(r) for r in mark_list]
        else:
            locks = ['{:.2f}'.format(r) for r in mark_list]

        style = {'marginBottom': '2em'}
        if invisible:
            style['display'] = 'none'

        new_slider = html.Div([
                        html.Label(label),
                        daq.Slider(
                            id=new_id,
                            min=min_val,
                            max=max_val,
                            value=init_val,
                            handleLabel={
                                "showCurrentValue": True,
                                "label": ' ',
                                "style": {"positionBottom": -1}},
                            marks=dict(zip(keys, locks)),
                            step=step_size,
                            size=725
                        )
                    ], style=style)
        self._sliders += [new_slider]
        self._slider_ids.append(new_id)




    def get_sliders_div(self):
        """
        Combines all sliders into a html.Div object.
        """
        return html.Div(self._sliders)




    def slider_ids(self):
        """
        Returns list of all slider IDs.
        """
        return self._slider_ids