tkinter与matplotlib

Question

我读过可以在tkinter中嵌入一个pyplot,但是我遇到了一个问题:

我需要显示一些帧,其中在主窗口的Tkinter的框架的pyplot,并且它必须以我的按键反应.

根据http://matplotlib.org/examples/user_interfaces/embedding_in_tk.html, 这适用:

#!/usr/bin/env python
from Tkinter import *
import matplotlib
matplotlib.use('TkAgg')    
from numpy import arange, sin, pi
from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg, NavigationToolbar2TkAgg
import matplotlib.backend_bases       
from matplotlib.figure import Figure    
import sys
if sys.version_info[0] < 3:
    import Tkinter as Tk
else:
    import tkinter as Tk

root = Tk.Tk()
root.wm_title("Embedding in TK")


f = Figure(figsize=(5,4), dpi=100)
a = f.add_subplot(111)
t = arange(0.0,3.0,0.01)
s = sin(2*pi*t)

a.plot(t,s)

canvas = FigureCanvasTkAgg(f, master=root)
canvas.show()
canvas.get_tk_widget().pack(side=Tk.TOP, fill=Tk.BOTH, expand=1)

canvas._tkcanvas.pack(side=Tk.TOP, fill=Tk.BOTH, expand=1)

def on_key_event(event):
    print('you pressed %s'%event.key)

canvas.mpl_connect('key_press_event', on_key_event)

def _quit():
    root.quit()     # stops mainloop
    root.destroy()  # this is necessary on Windows to prevent
                    # Fatal Python Error: PyEval_RestoreThread: NULL tstate

button = Tk.Button(master=root, text='Quit', command=_quit)
button.pack(side=Tk.BOTTOM)

Tk.mainloop()

我很高兴...但是如果我尝试在其上面有一个Text框架:

t=Text(root)
t.pack()

(在canvas变量定义之前)一旦我单击Text框架并写入它,就无法点击pyplot窗口并使其再次捕获我的按键!

任何提示？

Answer 1

在tkinter中,关键事件被路由到获得焦点的小部件,因此您的问题是将焦点设置回画布.这可以通过单击画布上的绑定来设置焦点.

例如:

canvas.mpl_connect('button_press_event', lambda event:canvas._tkcanvas.focus_set())
#or canvas._tkcanvas.bind('<Button1>', ...)