# -*- coding: utf-8 -*-
"""
Author: Juliette Monsel
License: GNU GPLv3
Source: https://github.com/j4321/tkColorPicker
Edited by RedFantom for Python 2/3 cross-compatibility and docstring formatting
tkcolorpicker - Alternative to colorchooser for Tkinter.
Copyright 2017 Juliette Monsel <j_4321@protonmail.com>
tkcolorpicker is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
tkcolorpicker is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
HSV gradient bar
"""
from .functions import tk, round2, rgb_to_hexa, hue2col
[docs]class GradientBar(tk.Canvas):
"""HSV gradient colorbar with selection cursor."""
[docs] def __init__(self, parent, hue=0, height=11, width=256, variable=None,
**kwargs):
"""
Create a GradientBar.
:param parent: parent widget
:type parent: widget
:param hue: initially selected hue value (between 0 and 360)
:type hue: int
:param variable: variable linked to the hue value
:type variable: IntVar
:param height: height of the widget in pixels
:type height: int
:param width: width of the widget in pixels
:type width: int
:param kwargs: options to be passed on to the :class:`tk.Canvas` initializer
"""
tk.Canvas.__init__(self, parent, width=width, height=height, **kwargs)
self._variable = variable
if variable is not None:
try:
hue = int(variable.get())
except Exception:
pass
else:
self._variable = tk.IntVar(self)
if hue > 360:
hue = 360
elif hue < 0:
hue = 0
self._variable.set(hue)
try:
self._variable.trace_add("write", self._update_hue)
except Exception:
self._variable.trace("w", self._update_hue)
self.gradient = tk.PhotoImage(master=self, width=width, height=height)
self.bind('<Configure>', lambda e: self._draw_gradient(hue))
self.bind('<ButtonPress-1>', self._on_click)
self.bind('<B1-Motion>', self._on_move)
def _draw_gradient(self, hue):
"""Draw the gradient and put the cursor on hue."""
self.delete("gradient")
self.delete("cursor")
del self.gradient
width = self.winfo_width()
height = self.winfo_height()
self.gradient = tk.PhotoImage(master=self, width=width, height=height)
line = []
for i in range(width):
line.append(rgb_to_hexa(*hue2col(float(i) / width * 360)))
line = "{" + " ".join(line) + "}"
self.gradient.put(" ".join([line for j in range(height)]))
self.create_image(0, 0, anchor="nw", tags="gardient",
image=self.gradient)
self.lower("gradient")
x = hue / 360. * width
self.create_line(x, 0, x, height, width=2, tags='cursor')
def _on_click(self, event):
"""Move selection cursor on click."""
x = event.x
self.coords('cursor', x, 0, x, self.winfo_height())
self._variable.set(round2((360. * x) / self.winfo_width()))
def _on_move(self, event):
"""Make selection cursor follow the cursor."""
w = self.winfo_width()
x = min(max(event.x, 0), w)
self.coords('cursor', x, 0, x, self.winfo_height())
self._variable.set(round2((360. * x) / w))
def _update_hue(self, *args):
hue = int(self._variable.get())
if hue > 360:
hue = 360
elif hue < 0:
hue = 0
self.set(hue)
self.event_generate("<<HueChanged>>")
[docs] def get(self):
"""Return hue of color under cursor."""
coords = self.coords('cursor')
return round2(360 * coords[0] / self.winfo_width())
[docs] def set(self, hue):
"""
Set cursor position on the color corresponding to the hue value.
:param hue: new hue value (between 0 and 360)
:type hue: int
"""
if hue > 360:
hue = 360
elif hue < 0:
hue = 0
x = hue / 360. * self.winfo_width()
self.coords('cursor', x, 0, x, self.winfo_height())
self._variable.set(hue)