实现鼠标交互

1. 实现鼠标点击节点高亮

直接上代码：

# -*- coding: utf-8 -*-

# -*- coding: utf-8 -*-

import matplotlib.pyplot as plt

from matplotlib.patches import Rectangle

import numpy as np

fig, ax = plt.subplots(figsize=(10,10))

node_pos = [(1, 0), (0, 1), (2,1), (1,2)]

bbox_args = dict(boxstyle="round", fc="0.8")

arrow_args = dict(arrowstyle="->")

an1 = plt.annotate(s="Test 1\n(node1,node2)\n(node3,node4,node5)\n\n\n", xy=node_pos[0], xycoords="data",

va="center", ha="center",

bbox=dict(boxstyle="round", fc="w", facecolor='green'))

an2 = plt.annotate(s="Test 2\n(node1,node2)", xy=node_pos[1], xycoords="data",

va="center", ha="center",

bbox=dict(boxstyle="round", fc="w", facecolor='green'))

arrow1 = plt.annotate('', xy=(0, 0), xycoords=an1,

xytext=(0, 0), textcoords=an2, # an1 -> an2

size=20, ha="center", va="center",

bbox=bbox_args,

arrowprops=dict(patchA=an2,

patchB=an1,

connectionstyle="arc3,rad=0.2",

#color='red',

#linewidth=5,

**arrow_args))

arrow2 = plt.annotate('', xy=(0, 0), xycoords=an2,

xytext=(0, 0), textcoords=an1, # an1 -> an2

size=20, ha="center", va="center",

bbox=bbox_args,

arrowprops=dict(patchA=an1,

patchB=an2,

connectionstyle="arc3,rad=0.2",

#color='red',

#linewidth=5,

**arrow_args))

# callback fun

def mouse_click(event):

if an1.contains(event)[0] == True: # 获取鼠标事件

an1.set_bbox(dict(facecolor='red', alpha= 0.5, boxstyle= 'round'))

fig.canvas.draw() # 切记要加上这句，否则，回调函数中的参数无法更新

axes = plt.gca()

axes.set_xlim([-2,2])

axes.set_ylim([-2,2])

fig.canvas.mpl_connect('button_press_event', mouse_click)

主要就是实现回调函数onclick。通过点击test1，实现背景高亮。

注意

切记要加上fig.canvas.draw()，否则回调函数中的参数无法更新。这个bug找了好久，都是泪。

2. 实现鼠标悬停在节点，显示节点信息。

# -*- coding: utf-8 -*-

import matplotlib.pyplot as plt

from matplotlib.patches import Rectangle

import numpy as np

fig, ax = plt.subplots(figsize=(10,10))

node_pos = [(1, 0), (0, 1), (2,1), (1,2)]

bbox_args = dict(boxstyle="round", fc="0.8")

arrow_args = dict(arrowstyle="->")

an1 = plt.annotate(s="Test 1\n(node1,node2)\n(node3,node4,node5)\n\n\n", xy=node_pos[0], xycoords="data",

va="center", ha="center",

bbox=bbox_args)

an2 = plt.annotate(s="Test 2\n(node1,node2)", xy=node_pos[1], xycoords="data",

va="center", ha="center",

bbox=bbox_args)

arrow1 = plt.annotate('', xy=(0, 0), xycoords=an1,

xytext=(0, 0), textcoords=an2, # an1 -> an2

size=20, ha="center", va="center",

bbox=bbox_args,

arrowprops=dict(patchA=an2,

patchB=an1,

connectionstyle="arc3,rad=0.2",

#color='red',

#linewidth=5,

**arrow_args))

arrow2 = plt.annotate('', xy=(0, 0), xycoords=an2,

xytext=(0, 0), textcoords=an1, # an1 -> an2

size=20, ha="center", va="center",

bbox=bbox_args,

arrowprops=dict(patchA=an1,

patchB=an2,

connectionstyle="arc3,rad=0.2",

#color='red',

#linewidth=5,

**arrow_args))

#fig.canvas.draw()

node_pos = an1.get_position()

tag1 = plt.annotate(s='hello node1', xy=node_pos, xycoords='data',

color='red',

xytext=(node_pos[0] + 0.3, node_pos[1] + 0.3),

textcoords='data', horizontalalignment="left",

bbox=bbox_args,

annotation_clip=True

)

tag1.set_visible(False)

# callback fun

def mouse_click(event):

if an1.contains(event)[0] == True: # 获取鼠标事件

if an1.get_color() != 'red':

an1.set_color('red') # set font color

an1.set_bbox(dict(facecolor='yellow', alpha=1, boxstyle='round'))

else:

an1.set_color('black') # set font color

an1.set_bbox(bbox_args)

fig.canvas.draw() # 切记要加上这句，否则，回调函数中的参数无法更新

# check mouse enter

def mouse_enter(event):

visible_change_flag = False

visible_flag = an1.contains(event)[0] #注意，这里检查节点an1是否包含鼠标，而不是tag1

if visible_flag != tag1.get_visible():

visible_change_flag = True

tag1.set_visible(visible_flag)

if visible_change_flag:

fig.canvas.draw()

axes = plt.gca()

axes.set_xlim([-2,2])

axes.set_ylim([-2,2])

fig.canvas.mpl_connect('button_press_event', mouse_click)

fig.canvas.mpl_connect('motion_notify_event', mouse_enter)

效果图

注意

这里检查节点an1是否包含鼠标，而不是tag1

鼠标悬停事件是motion_notify_event，而不是button_press_event