如何在Matplotlib结合Tkinter时保持默认光标状态？

我正在使用Matplotlib搭配Tkinter开发，代码如下：

from tkinter import *
import matplotlib.pyplot as plt
from matplotlib.figure import Figure
from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg, NavigationToolbar2Tk

root = Tk()

graph_frame=Frame(root,bg="red",height=10,width=10)
graph_frame.pack(side=TOP)

fig = Figure(figsize=(5, 4), dpi=100)
a=fig.add_subplot(1,1,1)

x = [1,3,12,15,1]
y = [10,9,8,55,19]

a.plot(x,y)

canvas = FigureCanvasTkAgg(fig, master=graph_frame)  # A tk.DrawingArea.
canvas.draw()
canvas.get_tk_widget().pack(side=TOP, expand=1)

toolbar = NavigationToolbar2Tk(canvas, graph_frame) # toolbar
toolbar.update()
canvas.get_tk_widget().pack(side=TOP, expand=1)

root.mainloop()

当点击缩放（zoom）或平移（pan）按钮时，光标会变为放大镜或十字移动光标，我希望光标始终保持默认模式，请问该如何实现？

提供两种简单有效的实现方式：

方法1：重写工具栏的光标设置方法 #

自定义继承自NavigationToolbar2Tk的工具栏类，重写set_cursor方法，彻底阻止工具栏修改光标：

from tkinter import *
import matplotlib.pyplot as plt
from matplotlib.figure import Figure
from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg, NavigationToolbar2Tk

# 自定义工具栏，禁用光标切换逻辑
class CustomToolbar(NavigationToolbar2Tk):
    def set_cursor(self, cursor):
        # 空实现，不执行任何光标修改操作
        pass

root = Tk()

graph_frame=Frame(root,bg="red",height=10,width=10)
graph_frame.pack(side=TOP)

fig = Figure(figsize=(5, 4), dpi=100)
a=fig.add_subplot(1,1,1)

x = [1,3,12,15,1]
y = [10,9,8,55,19]

a.plot(x,y)

canvas = FigureCanvasTkAgg(fig, master=graph_frame)
canvas.draw()
canvas.get_tk_widget().pack(side=TOP, expand=1)

# 使用自定义工具栏替代默认工具栏
toolbar = CustomToolbar(canvas, graph_frame)
toolbar.update()
canvas.get_tk_widget().pack(side=TOP, expand=1)

root.mainloop()

方法2：绑定画布事件强制重置光标 #

通过监听鼠标进入画布的事件，强制将光标设置为默认箭头：

from tkinter import *
import matplotlib.pyplot as plt
from matplotlib.figure import Figure
from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg, NavigationToolbar2Tk

root = Tk()

graph_frame=Frame(root,bg="red",height=10,width=10)
graph_frame.pack(side=TOP)

fig = Figure(figsize=(5, 4), dpi=100)
a=fig.add_subplot(1,1,1)

x = [1,3,12,15,1]
y = [10,9,8,55,19]

a.plot(x,y)

canvas = FigureCanvasTkAgg(fig, master=graph_frame)
canvas.draw()
canvas_widget = canvas.get_tk_widget()
canvas_widget.pack(side=TOP, expand=1)

# 强制光标为默认箭头
def reset_cursor(event):
    canvas_widget.config(cursor="arrow")

canvas_widget.bind("<Enter>", reset_cursor)

toolbar = NavigationToolbar2Tk(canvas, graph_frame)
toolbar.update()
canvas_widget.pack(side=TOP, expand=1)

root.mainloop()

说明 #

• 方法1从根源上禁用了所有工具栏的光标切换逻辑，是最彻底的方案；
• 方法2通过事件监听补强制重置光标，适合不需要完全修改工具栏逻辑的场景。

内容的提问来源于stack exchange，提问作者cak3_lover