from typing import Optional
from uuid import uuid4
from PIL import Image, ImageDraw
from arcade import Texture
from arcade.gui import UIClickable
from arcade.gui.ui_style import UIStyle
[docs]class UIToggle(UIClickable):
"""
A toggle which can be `true` or `false`.
Style attributes:
* color_true: color of the lever when value is `true`
* bg_color_true: color of the background when value is `true`
* color_false: color of the lever when value is `false`
* bg_color_false: color of the background when value is `false`
"""
[docs] def __init__(self,
center_x: int = 0,
center_y: int = 0,
height: int = 0,
value: bool = True,
id: Optional[str] = None,
style: UIStyle = None,
**kwargs):
"""
:param center_x: center X of element
:param center_y: center y of element
:param height: height of element, width depends on height
:param value: initial value
:param id: id of :py:class:`arcade.gui.UIElement`
:param style: style of :py:class:`arcade.gui.UIElement`
:param kwargs: catches unsupported named parameters
"""
super().__init__(
center_x=center_x,
center_y=center_y,
id=id,
style=style,
**kwargs
)
self.style_classes.append('toggle')
self.register_event_type('on_toggle')
self._height = height
self._value = value
self._true_texture: Optional[Texture] = None
self._false_texture: Optional[Texture] = None
self.render()
self.set_proper_texture()
@property
def value(self) -> bool:
"""
current value
"""
return self._value
@value.setter
def value(self, value: bool):
self._value = value
self.dispatch_event('on_toggle', value)
self.set_proper_texture()
[docs] def toggle(self):
"""
Toggles current value (True => False, False => True)
"""
self.value = not self.value
[docs] def on_click(self):
self.value = not self.value
self.set_proper_texture()
[docs] def on_toggle(self, value):
"""
Called if value changes through programmatic change or user interaction.
"""
pass
@staticmethod
def _round_corner(radius, fill):
"""Draw a round corner"""
corner = Image.new('RGBA', (radius, radius), (0, 0, 0, 0))
draw = ImageDraw.Draw(corner)
draw.pieslice((0, 0, radius * 2, radius * 2), 180, 270, fill=fill)
return corner
@staticmethod
def _round_rectangle(size, radius, fill):
"""Draw a rounded rectangle"""
width, height = size
rectangle = Image.new('RGBA', size, fill)
corner = UIToggle._round_corner(radius, fill)
rectangle.paste(corner, (0, 0))
rectangle.paste(corner.rotate(90), (0, height - radius)) # Rotate the corner and paste it
rectangle.paste(corner.rotate(180), (width - radius, height - radius))
rectangle.paste(corner.rotate(270), (width - radius, 0))
return rectangle
def _render_toggle(self, right: bool, color, bg_color) -> Texture:
height = self._height
width = self._height * 2
border_radius = height // 2
radius = height * 0.42
padding = radius * 0.16
pos_y = height // 2
pos_x = width - radius - padding if right else radius + padding
# Scale to look pretty
SCALE = 2
width *= SCALE
height *= SCALE
border_radius *= SCALE
radius *= SCALE
padding *= SCALE
pos_x *= SCALE
pos_y *= SCALE
# False
switch = UIToggle._round_rectangle((width, height), border_radius, bg_color)
d = ImageDraw.Draw(switch)
d.ellipse((pos_x - radius, pos_y - radius, pos_x + radius, pos_y + radius), fill=color)
switch = switch.resize((switch.width // SCALE, switch.height // SCALE), resample=Image.LANCZOS)
return Texture(name=str(uuid4()), image=switch)
[docs] def render(self):
color_true = self.style_attr('color_true')
bg_color_true = self.style_attr('bg_color_true')
self._true_texture = self._render_toggle(True, color_true, bg_color_true)
color_false = self.style_attr('color_false')
bg_color_false = self.style_attr('bg_color_false')
self._false_texture = self._render_toggle(False, color_false, bg_color_false)
self.set_proper_texture()
[docs] def set_proper_texture(self):
if self.value:
self.texture = self._true_texture
else:
self.texture = self._false_texture