【Python】Kivyを使ってシンプルなペイントツールを作成する方法

paint.py

from kivy.app import App
from kivy.uix.widget import Widget
from kivy.graphics import Color, Ellipse, Line

class MyPaintWidget(Widget):
    def on_touch_down(self, touch):
        with self.canvas:
            Color(1, 1, 0)
            touch.ud['line'] = Line(points=(touch.x, touch.y))

    def on_touch_move(self, touch):
        touch.ud["line"].points += [touch.x, touch.y]

class MyPaintApp(App):
    def build(self):
        return MyPaintWidget()

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