python Matplotlib底图中鼠标滑过显示隐藏内容的实例代码

# -*- coding: UTF-8 -*-
import matplotlib.pyplot as plt
fig = plt.figure()
po_annotation = []
for i in range(0, 10):
  x = i
  y = x**2
  point, = plt.plot(x, y, 'o')
  annotation = plt.annotate(('x='+str(x), 'y='+str(y)), xy=(x+0.1, y+0.1), xycoords='data', xytext=(x+0.7, y+0.7),
                textcoords='data', horizontalalignment="left",
                arrowprops=dict(arrowstyle="simple",connectionstyle="arc3,rad=-0.1"),
                bbox=dict(boxstyle="round", facecolor="w",edgecolor="0.5", alpha=0.9)
                )
  annotation.set_visible(False)
  po_annotation.append([point, annotation])
def on_move(event):
  visibility_changed = False
  for point, annotation in po_annotation:
    should_be_visible = (point.contains(event)[0] == True)
    # print(point.contains(event)[0])
    if should_be_visible != annotation.get_visible():
      visibility_changed = True
      annotation.set_visible(should_be_visible)
  if visibility_changed:
    plt.draw()
on_move_id = fig.canvas.mpl_connect('motion_notify_event', on_move)
plt.show()