Source code for slider

# SPDX-FileCopyrightText: 2021 Jose David
#
# SPDX-License-Identifier: MIT
"""

`slider`
================================================================================
A slider widget with a rectangular shape.

* Author(s): Jose David M.

Implementation Notes
--------------------

**Hardware:**

**Software and Dependencies:**

* Adafruit CircuitPython firmware for the supported boards:
  https://github.com/adafruit/circuitpython/releases

"""

################################
# A slider widget for CircuitPython, using displayio and adafruit_display_shapes
#
# Features:
#  - slider to represent non discrete values
#
# Future options to consider:
# ---------------------------
# different orientations (horizontal, vertical, flipped)
#

from adafruit_display_shapes.roundrect import RoundRect
from adafruit_displayio_layout.widgets.widget import Widget
from adafruit_displayio_layout.widgets.control import Control
from adafruit_displayio_layout.widgets.easing import quadratic_easeinout as easing

try:
    from typing import Tuple
except ImportError:
    pass

__version__ = "0.0.0-auto.0"
__repo__ = "https://github.com/jposada202020/CircuitPython_slider.git"


[docs]class Slider(Widget, Control): """ :param int x: pixel position, defaults to 0 :param int y: pixel position, defaults to 0 :param int width: width of the slider in pixels. It is recommended to use 100 the height will auto-size relative to the width. Defaults to :const:`100` :param int height: height of the slider in pixels, defaults to 40 pixels :param int touch_padding: the width of an additional border surrounding the switch that extends the touch response boundary, defaults to 0 :param anchor_point: starting point for the annotation line, where ``anchor_point`` is an (A,B) tuple in relative units of the size of the widget, for example (0.0, 0.0) is the upper left corner, and (1.0, 1.0) is the lower right corner of the widget. If :attr:`anchor_point` is `None`, then :attr:`anchored_position` is used to set the annotation line starting point, in widget size relative units. Defaults to :const:`(0.0, 0.0)` :type anchor_point: Tuple[float, float] :param anchored_position: pixel position starting point for the annotation line where :attr:`anchored_position` is an (x,y) tuple in pixel units relative to the upper left corner of the widget, in pixel units (default is None). :type anchored_position: Tuple[int, int] :param fill_color: (*RGB tuple or 24-bit hex value*) slider fill color, default is :const:`(66, 44, 66)` gray. :param outline_color: (*RGB tuple or 24-bit hex value*) slider outline color, default is :const:`(30, 30, 30)` dark gray. :param background_color: (*RGB tuple or 24-bit hex value*) background color, default is :const:`(255, 255, 255)` white :param int switch_stroke: outline stroke width for the switch and background, in pixels, default is 2 :param Boolean value: the initial value for the switch, default is False **Quickstart: Importing and using Slider** Here is one way of importing the `Slider` class so you can use it as the name ``Slider``: .. code-block:: python from adafruit_displayio_layout.widgets.slider import Slider Now you can create a Slider at pixel position x=20, y=30 using: .. code-block:: python my_slider=Slider(x=20, y=30) Once your setup your display, you can now add ``my_slider`` to your display using: .. code-block:: python display.show(my_slider) # add the group to the display If you want to have multiple display elements, you can create a group and then append the slider and the other elements to the group. Then, you can add the full group to the display as in this example: .. code-block:: python my_slider= Slider(20, 30) my_group = displayio.Group() # make a group my_group.append(my_slider) # Add my_slider to the group # # Append other display elements to the group # display.show(my_group) # add the group to the display **Summary: Slider Features and input variables** The ``Slider`` widget has some options for controlling its position, visible appearance, and value through a collection of input variables: - **position**: :const:`x`, ``y`` or ``anchor_point`` and ``anchored_position`` - **size**: :const:`width` and ``height`` (recommend to leave ``height`` = None to use preferred aspect ratio) - **switch color**: :const:`fill_color`, :const:`outline_color` - **background color**: :const:`background_color` - **linewidths**: :const:`switch_stroke` - **value**: Set ``value`` to the initial value (True or False) - **touch boundaries**: :attr:`touch_padding` defines the number of additional pixels surrounding the switch that should respond to a touch. (Note: The ``touch_padding`` variable updates the ``touch_boundary`` Control class variable. The definition of the ``touch_boundary`` is used to determine the region on the Widget that returns `True` in the `when_inside` function.) **The Slider Widget** .. figure:: slider.png :scale: 100 % :figwidth: 80% :align: center :alt: Diagram of the slider widget. This is a diagram of a slider with component parts """ def __init__( self, x: int = 0, y: int = 0, width: int = 100, # recommend to default to height: int = 40, touch_padding: int = 0, anchor_point: Tuple[int, int] = None, anchored_position: Tuple[int, int] = None, fill_color: Tuple[int, int, int] = (66, 44, 66), outline_color: Tuple[int, int, int] = (30, 30, 30), background_color: Tuple[int, int, int] = (255, 255, 255), value: bool = False, **kwargs, ) -> None: Widget.__init__(self, x=x, y=y, height=height, width=width, **kwargs) Control.__init__(self) self._knob_width = height // 2 self._knob_height = height self._knob_x = self._knob_width self._knob_y = self._knob_height self._slider_height = height // 5 self._height = self.height # pylint: disable=access-member-before-definition) if self._width is None: self._width = 100 else: self._width = self.width self._fill_color = fill_color self._outline_color = outline_color self._background_color = background_color self._switch_stroke = 2 self._touch_padding = touch_padding self._value = value self._anchor_point = anchor_point self._anchored_position = anchored_position self._create_slider() def _create_slider(self) -> None: # The main function that creates the switch display elements self._x_motion = self._width self._y_motion = 0 self._frame = RoundRect( x=0, y=0, width=self.width, height=self.height, r=4, fill=0x990099, outline=self._outline_color, stroke=self._switch_stroke, ) self._switch_handle = RoundRect( x=0, y=0, width=self._knob_width, height=self._knob_height, r=4, fill=self._fill_color, outline=self._outline_color, stroke=self._switch_stroke, ) self._switch_roundrect = RoundRect( x=2, y=self.height // 2 - self._slider_height // 2, r=2, width=self._width - 4, height=self._slider_height, fill=self._background_color, outline=self._background_color, stroke=self._switch_stroke, ) self._bounding_box = [ 0, 0, self.width, self._knob_height, ] self.touch_boundary = [ self._bounding_box[0] - self._touch_padding, self._bounding_box[1] - self._touch_padding, self._bounding_box[2] + 2 * self._touch_padding, self._bounding_box[3] + 2 * self._touch_padding, ] self._switch_initial_x = self._switch_handle.x self._switch_initial_y = self._switch_handle.y for _ in range(len(self)): self.pop() self.append(self._frame) self.append(self._switch_roundrect) self.append(self._switch_handle) self._update_position() def _get_offset_position(self, position) -> Tuple[int, int]: x_offset = int(self._x_motion * position // 2) y_offset = int(self._y_motion * position) return x_offset, y_offset def _draw_position(self, position: Tuple[int, int]) -> None: # apply the "easing" function to the requested position to adjust motion position = easing(position) # Get the position offset from the motion function x_offset, y_offset = self._get_offset_position(position) # Update the switch x- and y-positions self._switch_handle.x = self._switch_initial_x + x_offset self._switch_handle.y = self._switch_initial_y + y_offset
[docs] def when_selected(self, touch_point: int) -> int: """ Manages internal logic when widget is selected """ if touch_point[0] <= self.x + self._knob_width: touch_x = touch_point[0] - self.x else: touch_x = touch_point[0] - self.x - self._knob_width touch_y = touch_point[1] - self.y self.selected((touch_x, touch_y, 0)) self._switch_handle.x = touch_x return self._switch_handle.x
[docs] def when_inside(self, touch_point: int) -> bool: """Checks if the Widget was touched. :param touch_point: x,y location of the screen, in absolute display coordinates. :return: Boolean """ touch_x = ( touch_point[0] - self.x ) # adjust touch position for the local position touch_y = touch_point[1] - self.y return self.contains((touch_x, touch_y, 0))
@property def value(self) -> int: """The current switch value (Boolean). :return: Boolean """ return self._value