CustomTkinter/customtkinter/windows/widgets/ctk_scrollbar.py
2022-12-06 19:25:00 +01:00

282 lines
14 KiB
Python

import sys
from typing import Union, Tuple, Callable, Optional
from .core_rendering import CTkCanvas
from .theme import ThemeManager
from .core_rendering import DrawEngine
from .core_widget_classes import CTkBaseClass
class CTkScrollbar(CTkBaseClass):
"""
Scrollbar with rounded corners, configurable spacing.
Connect to scrollable widget by passing .set() method and set command attribute.
For detailed information check out the documentation.
"""
def __init__(self,
master: any,
width: Optional[Union[int, str]] = None,
height: Optional[Union[int, str]] = None,
corner_radius: Optional[int] = None,
border_spacing: Optional[int] = None,
minimum_pixel_length: int = 20,
bg_color: Union[str, Tuple[str, str]] = "transparent",
fg_color: Optional[Union[str, Tuple[str, str]]] = None,
button_color: Optional[Union[str, Tuple[str, str]]] = None,
button_hover_color: Optional[Union[str, Tuple[str, str]]] = None,
hover: bool = True,
command: Union[Callable, None] = None,
orientation: str = "vertical",
**kwargs):
# set default dimensions according to orientation
if width is None:
if orientation.lower() == "vertical":
width = 16
else:
width = 200
if height is None:
if orientation.lower() == "horizontal":
height = 16
else:
height = 200
# transfer basic functionality (_bg_color, size, __appearance_mode, scaling) to CTkBaseClass
super().__init__(master=master, bg_color=bg_color, width=width, height=height, **kwargs)
# color
self._fg_color = ThemeManager.theme["CTkScrollbar"]["fg_color"] if fg_color is None else self._check_color_type(fg_color, transparency=True)
self._button_color = ThemeManager.theme["CTkScrollbar"]["button_color"] if button_color is None else self._check_color_type(button_color)
self._button_hover_color = ThemeManager.theme["CTkScrollbar"]["button_hover_color"] if button_hover_color is None else self._check_color_type(button_hover_color)
# shape
self._corner_radius = ThemeManager.theme["CTkScrollbar"]["corner_radius"] if corner_radius is None else corner_radius
self._border_spacing = ThemeManager.theme["CTkScrollbar"]["border_spacing"] if border_spacing is None else border_spacing
self._hover = hover
self._hover_state: bool = False
self._command = command
self._orientation = orientation
self._start_value: float = 0 # 0 to 1
self._end_value: float = 1 # 0 to 1
self._minimum_pixel_length = minimum_pixel_length
self._canvas = CTkCanvas(master=self,
highlightthickness=0,
width=self._apply_widget_scaling(self._current_width),
height=self._apply_widget_scaling(self._current_height))
self._canvas.place(x=0, y=0, relwidth=1, relheight=1)
self._draw_engine = DrawEngine(self._canvas)
self._create_bindings()
self._draw()
def _create_bindings(self, sequence: Optional[str] = None):
""" set necessary bindings for functionality of widget, will overwrite other bindings """
if sequence is None:
self._canvas.tag_bind("border_parts", "<Button-1>", self._clicked)
if sequence is None or sequence == "<Enter>":
self._canvas.bind("<Enter>", self._on_enter)
if sequence is None or sequence == "<Leave>":
self._canvas.bind("<Leave>", self._on_leave)
if sequence is None or sequence == "<B1-Motion>":
self._canvas.bind("<B1-Motion>", self._clicked)
if sequence is None or sequence == "<MouseWheel>":
self._canvas.bind("<MouseWheel>", self._mouse_scroll_event)
def _set_scaling(self, *args, **kwargs):
super()._set_scaling(*args, **kwargs)
self._canvas.configure(width=self._apply_widget_scaling(self._desired_width),
height=self._apply_widget_scaling(self._desired_height))
self._draw(no_color_updates=True)
def _set_dimensions(self, width=None, height=None):
super()._set_dimensions(width, height)
self._canvas.configure(width=self._apply_widget_scaling(self._desired_width),
height=self._apply_widget_scaling(self._desired_height))
self._draw(no_color_updates=True)
def _get_scrollbar_values_for_minimum_pixel_size(self):
# correct scrollbar float values if scrollbar is too small
if self._orientation == "vertical":
scrollbar_pixel_length = (self._end_value - self._start_value) * self._current_height
if scrollbar_pixel_length < self._minimum_pixel_length and -scrollbar_pixel_length + self._current_height != 0:
# calculate how much to increase the float interval values so that the scrollbar width is self.minimum_pixel_length
interval_extend_factor = (-scrollbar_pixel_length + self._minimum_pixel_length) / (-scrollbar_pixel_length + self._current_height)
corrected_end_value = self._end_value + (1 - self._end_value) * interval_extend_factor
corrected_start_value = self._start_value - self._start_value * interval_extend_factor
return corrected_start_value, corrected_end_value
else:
return self._start_value, self._end_value
else:
scrollbar_pixel_length = (self._end_value - self._start_value) * self._current_width
if scrollbar_pixel_length < self._minimum_pixel_length and -scrollbar_pixel_length + self._current_width != 0:
# calculate how much to increase the float interval values so that the scrollbar width is self.minimum_pixel_length
interval_extend_factor = (-scrollbar_pixel_length + self._minimum_pixel_length) / (-scrollbar_pixel_length + self._current_width)
corrected_end_value = self._end_value + (1 - self._end_value) * interval_extend_factor
corrected_start_value = self._start_value - self._start_value * interval_extend_factor
return corrected_start_value, corrected_end_value
else:
return self._start_value, self._end_value
def _draw(self, no_color_updates=False):
super()._draw(no_color_updates)
corrected_start_value, corrected_end_value = self._get_scrollbar_values_for_minimum_pixel_size()
requires_recoloring = self._draw_engine.draw_rounded_scrollbar(self._apply_widget_scaling(self._current_width),
self._apply_widget_scaling(self._current_height),
self._apply_widget_scaling(self._corner_radius),
self._apply_widget_scaling(self._border_spacing),
corrected_start_value,
corrected_end_value,
self._orientation)
if no_color_updates is False or requires_recoloring:
if self._hover_state is True:
self._canvas.itemconfig("scrollbar_parts",
fill=self._apply_appearance_mode(self._button_hover_color),
outline=self._apply_appearance_mode(self._button_hover_color))
else:
self._canvas.itemconfig("scrollbar_parts",
fill=self._apply_appearance_mode(self._button_color),
outline=self._apply_appearance_mode(self._button_color))
if self._fg_color == "transparent":
self._canvas.configure(bg=self._apply_appearance_mode(self._bg_color))
self._canvas.itemconfig("border_parts",
fill=self._apply_appearance_mode(self._bg_color),
outline=self._apply_appearance_mode(self._bg_color))
else:
self._canvas.configure(bg=self._apply_appearance_mode(self._fg_color))
self._canvas.itemconfig("border_parts",
fill=self._apply_appearance_mode(self._fg_color),
outline=self._apply_appearance_mode(self._fg_color))
self._canvas.update_idletasks()
def configure(self, require_redraw=False, **kwargs):
if "fg_color" in kwargs:
self._fg_color = self._check_color_type(kwargs.pop("fg_color"), transparency=True)
require_redraw = True
if "button_color" in kwargs:
self._button_color = self._check_color_type(kwargs.pop("button_color"))
require_redraw = True
if "button_hover_color" in kwargs:
self._button_hover_color = self._check_color_type(kwargs.pop("button_hover_color"))
require_redraw = True
if "hover" in kwargs:
self._hover = kwargs.pop("hover")
if "command" in kwargs:
self._command = kwargs.pop("command")
if "corner_radius" in kwargs:
self._corner_radius = kwargs.pop("corner_radius")
require_redraw = True
if "border_spacing" in kwargs:
self._border_spacing = kwargs.pop("border_spacing")
require_redraw = True
super().configure(require_redraw=require_redraw, **kwargs)
def cget(self, attribute_name: str) -> any:
if attribute_name == "corner_radius":
return self._corner_radius
elif attribute_name == "border_spacing":
return self._border_spacing
elif attribute_name == "minimum_pixel_length":
return self._minimum_pixel_length
elif attribute_name == "fg_color":
return self._fg_color
elif attribute_name == "scrollbar_color":
return self._button_color
elif attribute_name == "scrollbar_hover_color":
return self._button_hover_color
elif attribute_name == "hover":
return self._hover
elif attribute_name == "command":
return self._command
elif attribute_name == "orientation":
return self._orientation
else:
return super().cget(attribute_name)
def _on_enter(self, event=0):
if self._hover is True:
self._hover_state = True
self._canvas.itemconfig("scrollbar_parts",
outline=self._apply_appearance_mode(self._button_hover_color),
fill=self._apply_appearance_mode(self._button_hover_color))
def _on_leave(self, event=0):
self._hover_state = False
self._canvas.itemconfig("scrollbar_parts",
outline=self._apply_appearance_mode(self._button_color),
fill=self._apply_appearance_mode(self._button_color))
def _clicked(self, event):
if self._orientation == "vertical":
value = self._reverse_widget_scaling(((event.y - self._border_spacing) / (self._current_height - 2 * self._border_spacing)))
else:
value = self._reverse_widget_scaling(((event.x - self._border_spacing) / (self._current_width - 2 * self._border_spacing)))
current_scrollbar_length = self._end_value - self._start_value
value = max(current_scrollbar_length / 2, min(value, 1 - (current_scrollbar_length / 2)))
self._start_value = value - (current_scrollbar_length / 2)
self._end_value = value + (current_scrollbar_length / 2)
self._draw()
if self._command is not None:
self._command('moveto', self._start_value)
def _mouse_scroll_event(self, event=None):
if self._command is not None:
if sys.platform.startswith("win"):
self._command('scroll', -int(event.delta/40), 'units')
else:
self._command('scroll', -event.delta, 'units')
def set(self, start_value: float, end_value: float):
self._start_value = float(start_value)
self._end_value = float(end_value)
self._draw()
def get(self):
return self._start_value, self._end_value
def bind(self, sequence=None, command=None, add=True):
""" called on the tkinter.Canvas """
if not (add == "+" or add is True):
raise ValueError("'add' argument can only be '+' or True to preserve internal callbacks")
self._canvas.bind(sequence, command, add=True)
def unbind(self, sequence=None, funcid=None):
""" called on the tkinter.Canvas, restores internal callbacks """
if funcid is not None:
raise ValueError("'funcid' argument can only be None, because there is a bug in" +
" tkinter and its not clear whether the internal callbacks will be unbinded or not")
self._canvas.unbind(sequence, None) # unbind all callbacks for sequence
self._create_bindings(sequence=sequence) # restore internal callbacks for sequence
def focus(self):
return self._canvas.focus()
def focus_set(self):
return self._canvas.focus_set()
def focus_force(self):
return self._canvas.focus_force()