from __future__ import annotations
from abc import ABCMeta, abstractmethod
from dataclasses import dataclass
from typing import Optional, Union, Mapping
from pyglet.event import EVENT_HANDLED, EVENT_UNHANDLED
import arcade
from arcade import Texture
from arcade.gui import (
Surface,
UIEvent,
UIMouseDragEvent,
UIInteractiveWidget,
NinePatchTexture,
UIOnClickEvent,
)
from arcade.gui.events import UIOnChangeEvent
from arcade.gui.property import Property, bind
from arcade.gui.style import UIStyleBase, UIStyledWidget
from arcade.types import Color, RGBA255
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class UIBaseSlider(UIInteractiveWidget, metaclass=ABCMeta):
"""
Base class for sliders.
A slider contains of a horizontal track and a thumb.
The thumb can be moved along the track to set the value of the slider.
Use the `on_change` event to get notified about value changes.
Subclasses should implement the `_render_track` and `_render_thumb` methods.
"""
value = Property(0)
def __init__(
self,
*,
value: float = 0,
min_value: float = 0,
max_value: float = 100,
x: float = 0,
y: float = 0,
width: float = 300,
height: float = 20,
size_hint=None,
size_hint_min=None,
size_hint_max=None,
style: Union[Mapping[str, UISliderStyle], None] = None,
**kwargs,
):
super().__init__(
x=x,
y=y,
width=width,
height=height,
size_hint=size_hint,
size_hint_min=size_hint_min,
size_hint_max=size_hint_max,
style=style or UISlider.DEFAULT_STYLE,
**kwargs,
)
self.value = value
self.min_value = min_value
self.max_value = max_value
self._cursor_width = self.height // 3
# trigger render on value changes
bind(self, "value", self.trigger_full_render)
bind(self, "hovered", self.trigger_render)
bind(self, "pressed", self.trigger_render)
bind(self, "disabled", self.trigger_render)
self.register_event_type("on_change")
def _x_for_value(self, value: float):
"""Provides the x coordinate for the given value."""
x = self.content_rect.x
val = (value - self.min_value) / self.max_value
return x + self._cursor_width + val * (self.content_width - 2 * self._cursor_width)
@property
def norm_value(self):
"""Normalized value between 0.0 and 1.0"""
return (self.value - self.min_value) / self.max_value
@norm_value.setter
def norm_value(self, value):
"""Normalized value between 0.0 and 1.0"""
self.value = min(value * (self.max_value - self.min_value) + self.min_value, self.max_value)
@property
def _thumb_x(self):
"""Returns the current x coordinate of the thumb."""
return self._x_for_value(self.value)
@_thumb_x.setter
def _thumb_x(self, nx):
"""Set thumb x coordinate and update the value."""
rect = self.content_rect
x = min(rect.right - self._cursor_width, max(nx, rect.x + self._cursor_width))
if self.width == 0:
self.norm_value = 0
else:
self.norm_value = (x - rect.x - self._cursor_width) / float(self.content_width - 2 * self._cursor_width)
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def do_render(self, surface: Surface):
self.prepare_render(surface)
self._render_track(surface)
self._render_thumb(surface)
@abstractmethod
def _render_track(self, surface):
"""Render the track of the slider.
This method should be implemented in a slider implementation.
Track should stay within self.content_rect.
"""
pass
@abstractmethod
def _render_thumb(self, surface):
"""Render the thumb of the slider.
This method should be implemented in a slider implementation.
Thumb should stay within self.content_rect.
x coordinate of the thumb should be self._thumb_x.
"""
pass
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def on_event(self, event: UIEvent) -> Optional[bool]:
if super().on_event(event):
return EVENT_HANDLED
if isinstance(event, UIMouseDragEvent):
if self.pressed:
old_value = self.value
self._thumb_x = event.x
self.dispatch_event("on_change", UIOnChangeEvent(self, old_value, self.value)) # type: ignore
return EVENT_UNHANDLED
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def on_click(self, event: UIOnClickEvent):
old_value = self.value
self._thumb_x = event.x
self.dispatch_event("on_change", UIOnChangeEvent(self, old_value, self.value)) # type: ignore
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def on_change(self, event: UIOnChangeEvent):
"""To be implemented by the user, triggered when the cursor's value is changed."""
pass
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@dataclass
class UISliderStyle(UIStyleBase):
"""
Used to style the slider for different states. Below is its use case.
.. code:: py
button = UITextureButton(style={"normal": UITextureButton.UIStyle(...),})
"""
bg: RGBA255 = Color(94, 104, 117)
border: RGBA255 = Color(77, 81, 87)
border_width: int = 1
filled_track: RGBA255 = Color(50, 50, 50)
unfilled_track: RGBA255 = Color(116, 125, 123)
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class UISlider(UIStyledWidget[UISliderStyle], UIBaseSlider):
"""
A simple slider.
A slider contains of a horizontal track and a thumb.
The thumb can be moved along the track to set the value of the slider.
Use the `on_change` event to get notified about value changes.
There are four states of the UISlider i.e normal, hovered, pressed and disabled.
:param value: Current value of the curosr of the slider.
:param min_value: Minimum value of the slider.
:param max_value: Maximum value of the slider.
:param x: x coordinate of bottom left.
:param y: y coordinate of bottom left.
:param width: Width of the slider.
:param height: Height of the slider.
:param Mapping[str, "UISlider.UIStyle"] | None style: Used to style the slider for different states.
"""
UIStyle = UISliderStyle
DEFAULT_STYLE = {
"normal": UIStyle(),
"hover": UIStyle(
bg=Color(96, 103, 112),
border=Color(77, 81, 87),
border_width=2,
filled_track=Color(50, 50, 50),
unfilled_track=Color(116, 125, 123),
),
"press": UIStyle(
bg=Color(96, 103, 112),
border=Color(77, 81, 87),
border_width=3,
filled_track=Color(50, 50, 50),
unfilled_track=Color(116, 125, 123),
),
"disabled": UIStyle(
bg=Color(94, 104, 117),
border=Color(77, 81, 87),
border_width=1,
filled_track=Color(50, 50, 50),
unfilled_track=Color(116, 125, 123),
),
}
def __init__(
self,
*,
value: float = 0,
min_value: float = 0,
max_value: float = 100,
x: float = 0,
y: float = 0,
width: float = 300,
height: float = 20,
size_hint=None,
size_hint_min=None,
size_hint_max=None,
style: Union[Mapping[str, UISliderStyle], None] = None,
**kwargs,
):
super().__init__(
value=value,
min_value=min_value,
max_value=max_value,
x=x,
y=y,
width=width,
height=height,
size_hint=size_hint,
size_hint_min=size_hint_min,
size_hint_max=size_hint_max,
style=style or UISlider.DEFAULT_STYLE,
**kwargs,
)
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def get_current_state(self) -> str:
"""Returns the current state of the slider i.e disabled, press, hover or normal."""
if self.disabled:
return "disabled"
elif self.pressed:
return "press"
elif self.hovered:
return "hover"
else:
return "normal"
def _render_track(self, surface: Surface):
"""Render the track of the slider."""
style = self.get_current_style()
bg_slider_color = style.get("unfilled_track", UISlider.UIStyle.unfilled_track)
fg_slider_color = style.get("filled_track", UISlider.UIStyle.filled_track)
slider_height = self.content_height // 4
slider_left_x = self._x_for_value(self.min_value)
slider_right_x = self._x_for_value(self.max_value)
cursor_center_x = self._thumb_x
slider_bottom = (self.content_height - slider_height) // 2
arcade.draw_xywh_rectangle_filled(
slider_left_x - self.content_rect.x,
slider_bottom,
slider_right_x - slider_left_x,
slider_height,
bg_slider_color,
)
arcade.draw_xywh_rectangle_filled(
slider_left_x - self.content_rect.x,
slider_bottom,
cursor_center_x - slider_left_x,
slider_height,
fg_slider_color,
)
def _render_thumb(self, surface: Surface):
"""Render the thumb of the slider."""
style = self.get_current_style()
border_width = style.get("border_width", UISlider.UIStyle.border_width)
cursor_color = style.get("bg", UISlider.UIStyle.bg)
cursor_outline_color = style.get("border", UISlider.UIStyle.border)
cursor_radius = self._cursor_width
cursor_center_x = self._thumb_x
slider_center_y = self.content_height // 2
rel_cursor_x = cursor_center_x - self.content_rect.x
arcade.draw_circle_filled(rel_cursor_x, slider_center_y, cursor_radius, cursor_color)
arcade.draw_circle_filled(rel_cursor_x, slider_center_y, cursor_radius // 4, cursor_outline_color)
arcade.draw_circle_outline(
rel_cursor_x,
slider_center_y,
cursor_radius,
cursor_outline_color,
border_width,
)
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class UITextureSlider(UISlider):
"""
A custom slider subclass which supports textures.
You can copy this as-is into your own project, or you can modify
the class to have more features as needed.
"""
def __init__(
self,
track: Union[Texture, NinePatchTexture],
thumb: Union[Texture, NinePatchTexture],
style=None,
**kwargs,
):
self._track = track
self._thumb = thumb
super().__init__(style=style or UISlider.DEFAULT_STYLE, **kwargs)
def _render_track(self, surface: Surface):
style: UISliderStyle = self.get_current_style() # type: ignore
surface.draw_texture(0, 0, self.width, self.height, self._track)
# TODO accept these as constructor params
slider_height = self.height // 4
slider_left_x = self._x_for_value(self.min_value)
cursor_center_x = self._thumb_x
slider_bottom = (self.height - slider_height) // 2
# slider
arcade.draw_xywh_rectangle_filled(
slider_left_x - self.x,
slider_bottom,
cursor_center_x - slider_left_x,
slider_height,
style.filled_track,
)
def _render_thumb(self, surface: Surface):
cursor_center_x = self._thumb_x
rel_cursor_x = cursor_center_x - self.x
surface.draw_texture(
x=rel_cursor_x - self._thumb.width // 4 + 2,
y=0,
width=self._thumb.width // 2,
height=self.height,
tex=self._thumb,
)