python [Kivy] HSVA拾色器

Posted 2021-05-09

from kivy.app           import App
from kivy.graphics      import Color, Rectangle
from kivy.lang          import Builder
from kivy.uix.boxlayout import BoxLayout


Builder.load_string('''
<MyLayout>:
	orientation: "vertical"
	padding:     50, 50, 50, 50

	Label:
		id:            label
		font_name:     "RobotoMono-Regular"
		font_size:     25
		outline_color: 0.5,0.5,0.5
		outline_width: 1
		halign:        "right"

	Slider:
		id: h_slider
	Slider:
		id: s_slider
	Slider:
		id: v_slider
	Slider:
		id: a_slider
''')

class MyLayout(BoxLayout):
	initial_hsva     = (0, 0.5, 0.5, 1)
	background_color = None
	sliders          = None

	def __init__(self, **kwargs):
		super(MyLayout, self).__init__(**kwargs)

		h,s,v,a = self.initial_hsva
		with self.canvas.before:
			self.background_color = Color(h,s,v,a, mode="hsv")
			self.rect = Rectangle(pos=self.pos, size=self.size)

	def on_parent(self, widget, parent):
		self.bind(pos=self.update_rect, size=self.update_rect)

		self.sliders = (self.ids.h_slider, self.ids.s_slider, self.ids.v_slider, self.ids.a_slider)
		initial_slider_values = (x * 100  for x in self.initial_hsva)
		for slider, value in zip(self.sliders, initial_slider_values):
			slider.bind(
				on_touch_down = self.update_color,
				on_touch_move = self.update_color,
			)
			slider.value = value

		self.update_color(None, None)

	def update_rect(self, instance, size):
		self.rect.pos  = self.pos
		self.rect.size = self.size

	def update_color(self, instance, touch):
		h,s,v,a = (x.value / 100  for x in self.sliders)
		self.background_color.rgba = Color(h,s,v,a, mode="hsv").rgba

		h_string = str(round(h * 360)).rjust(3)
		s_string, v_string, a_string = (str(round(x * 100)).rjust(3)  for x in (s,v,a))
		self.ids.label.text = "H: {0}\nS: {1}\nV: {2}\nA: {3}".format(h_string, s_string, v_string, a_string)


class DemoApp(App):
	def build(self):
		return( MyLayout() )

if __name__ == "__main__":
	DemoApp().run()