Matplotlib/tkinter：在图例中挑选事件

Question

我无法修改此代码，因此可以通过单击图例在tkinter中选择一行。我想修改这个代码example

这是我到目前为止的代码。它只是在tkinter绘制线。

import tkinter as tk 
from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg 
from matplotlib.figure import Figure 

class Main: 
    def __init__(self, master): 
     self.master = master 
     master.title("A simple GUI") 

     plotFrame = tk.Frame(master) 
     plotFrame.pack() 

     f = Figure(figsize=(5,4),dpi=100) 
     self.ax = f.add_subplot(111) 
     self.canvas = FigureCanvasTkAgg(f,master=plotFrame) 
     self.canvas.show() 
     self.canvas.get_tk_widget().pack() 

     line1, = self.ax.plot(t, y1, lw=2, color='red', label='1 HZ') 
     line2, = self.ax.plot(t, y2, lw=2, color='blue', label='2 HZ') 
     leg = self.ax.legend(loc='upper left', fancybox=True, shadow=True) 
     leg.get_frame().set_alpha(0.4) 

    def onpick(event): 
     # on the pick event, find the orig line corresponding to the 
     # legend proxy line, and toggle the visibility 
     legline = event.artist 
     origline = lined[legline] 
     vis = not origline.get_visible() 
     origline.set_visible(vis) 
     # Change the alpha on the line in the legend so we can see what lines 
     # have been toggled 
     if vis: 
      legline.set_alpha(1.0) 
     else: 
      legline.set_alpha(0.2) 
     fig.canvas.draw() 

    fig.canvas.mpl_connect('pick_event', onpick) 

    plt.show() 



root = tk.Tk() 
my_gui = Main(root) 
root.mainloop() 

Answer 1

为了编写您的tkinter GUI in an object-oriented style，您需要更好地使用面向对象的结构。特别是：

保持类的方法中代码：

# In your example, the following lines are outside any method 
fig.canvas.mpl_connect('pick_event', onpick) 

plt.show() 

2-使用self变量来存储要在不同的方法来访问对象：

# Add self as the first argument in onpick() 
def onpick(self, event): 
    (...) 
    # Now you can access self.canvas defined in __init__() 
    self.canvas.draw() 

看到下面的代码的工作版本：

import tkinter as tk 
from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg 
from matplotlib.figure import Figure 
import numpy as np 

t = np.arange(0.0, 0.2, 0.1) 
y1 = 2*np.sin(2*np.pi*t) 
y2 = 4*np.sin(2*np.pi*2*t) 

class Main: 
    def __init__(self, master): 
     self.master = master 
     master.title("A simple GUI") 

     plotFrame = tk.Frame(master) 
     plotFrame.pack() 

     f = Figure(figsize=(5,4),dpi=100) 
     self.ax = f.add_subplot(111) 
     self.canvas = FigureCanvasTkAgg(f, master=plotFrame) 
     self.canvas.show() 
     self.canvas.get_tk_widget().pack() 
     self.canvas.mpl_connect('pick_event', self.onpick) 

     line1, = self.ax.plot(t, y1, lw=2, color='red', label='1 HZ') 
     line2, = self.ax.plot(t, y2, lw=2, color='blue', label='2 HZ') 
     leg = self.ax.legend(loc='upper left', fancybox=True, shadow=True) 
     leg.get_frame().set_alpha(0.4) 

     # we will set up a dict mapping legend line to orig line, and enable 
     # picking on the legend line 
     lines = [line1, line2] 
     self.lined = dict() 
     for legline, origline in zip(leg.get_lines(), lines): 
      legline.set_picker(5) # 5 pts tolerance 
      self.lined[legline] = origline 

    def onpick(self, event): 
     # on the pick event, find the orig line corresponding to the 
     # legend proxy line, and toggle the visibility 
     legline = event.artist 
     origline = self.lined[legline] 
     vis = not origline.get_visible() 
     origline.set_visible(vis) 
     # Change the alpha on the line in the legend so we can see what lines 
     # have been toggled 
     if vis: 
      legline.set_alpha(1.0) 
     else: 
      legline.set_alpha(0.2) 
     self.canvas.draw() 


root = tk.Tk() 
my_gui = Main(root) 
root.mainloop()