按下时更改matplotlib按钮的颜色

Question

我正在运行一个动画，使用matplotlib的FuncAnimation来显示来自微处理器的数据（实时）。我正在使用按钮向处理器发送命令，并希望在单击按钮后更改按钮的颜色，但我在matplotlib.widgets.button文档中找不到任何实现这一点的内容。

class Command:
    def motor(self, event):
    SERIAL['Serial'].write(' ')
    plt.draw()
write = Command()
bmotor = Button(axmotor, 'Motor', color = '0.85', hovercolor = 'g')
bmotor.on_clicked(write.motor)            #Change Button Color Here

Answer 1

只需设置button.color。

例如

import matplotlib.pyplot as plt
from matplotlib.widgets import Button
import itertools

fig, ax = plt.subplots()
button = Button(ax, 'Click me!')
colors = itertools.cycle(['red', 'green', 'blue'])
def change_color(event):
    button.color = next(colors)
    # If you want the button's color to change as soon as it's clicked, you'll
    # need to set the hovercolor, as well, as the mouse is still over it
    button.hovercolor = button.color
    fig.canvas.draw()
button.on_clicked(change_color)
plt.show()

Answer 2

在当前matplotlib版本（1.4.2）中，只有当鼠标"_motion"事件发生时，才会考虑"color"one_answers"hovercolor"，因此按钮的颜色不会在按下鼠标按钮时更改，而只会在之后移动鼠标时更改。

不过，您可以手动更改按钮背景：

import matplotlib.pyplot as plt
from matplotlib.widgets import Button
import itertools
button = Button(plt.axes([0.45, 0.45, 0.2, 0.08]), 'Blink!')

def button_click(event):
    button.ax.set_axis_bgcolor('teal')
    button.ax.figure.canvas.draw()
    # Also you can add timeout to restore previous background:
    plt.pause(0.2)
    button.ax.set_axis_bgcolor(button.color)
    button.ax.figure.canvas.draw()

button.on_clicked(button_click)
plt.show()

Answer 3

如果有人不想在更改颜色时将Button作为全局变量，这里有一个解决方案：

import matplotlib.pyplot as plt
from matplotlib.widgets import Button
def change_color(button):
    button.color = 'red'
def main():
    button = Button(plt.axes([0.5, 0.5, 0.25, 0.05]), 'Click here')
    button.on_clicked(lambda _: change_color(button))
    plt.show()
if __name__ == "__main__":
    main()