为什么在kivy的第一个小部件示例中,右键单击画布时会导致黄色圆形中间出现橙色圆形,而左键单击时则会生成纯黄色圆形?
from kivy.app import App
from kivy.uix.widget import Widget
from kivy.graphics import Color, Ellipse
class MyPaintWidget(Widget):
def on_touch_down(self, touch):
with self.canvas:
Color(1, 1, 0)
d = 30.
Ellipse(pos=(touch.x - d/2, touch.y - d/2), size=(d, d))
class MyPaintApp(App):
def build(self):
return MyPaintWidget()
if __name__ == '__main__':
MyPaintApp().run()