从 Tkinter gui 中更新 matplotlib imshow

Question

我正在尝试更新 Tkinter gui 中的 matplotlib imshow 窗口中的数据，我的代码示例如下：

#minimal example...

import matplotlib, sys
matplotlib.use('TkAgg')
from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg
from matplotlib import pylab as plt
from scipy import ndimage

if sys.version_info[0] < 3:
    import Tkinter as Tk
else:
    import tkinter as Tk

root = Tk.Tk()
root.wm_title("minimal example")

image = plt.imread('test.jpg')
fig = plt.figure(figsize=(5,4))
im = plt.imshow(image) # later use a.set_data(new_data)
ax = plt.gca()
ax.set_xticklabels([]) 
ax.set_yticklabels([]) 

# a tk.DrawingArea
canvas = FigureCanvasTkAgg(fig, master=root)
canvas.show()
canvas.get_tk_widget().pack(side=Tk.TOP, fill=Tk.BOTH, expand=1)

def rotate(*args):
    print 'rotate button press...'
    theta = 90
    rotated = ndimage.rotate(image, theta)
    im.set_data(rotated)
    root.update()

def quit(*args):
    print 'quit button press...'
    root.quit()     
    root.destroy() 

button_rotate = Tk.Button(master = root, text = 'Rotate', command = rotate)
button_quit = Tk.Button(master = root, text = 'Quit', command = quit)

button_quit.pack(side=Tk.LEFT)
button_rotate.pack()

Tk.mainloop()

如您所见，我使用 imshow() 加载图像，然后尝试使用 set_data() 更新图像的数据，然后想要使用 root.update() 更新 gui 的根窗口。执行时，打印“旋转按钮按下...”行被执行，但其余部分似乎没有执行。我是否需要以某种方式将图像句柄传递给旋转函数，或者返回旋转后的图像？

Answer 1

画布需要重新绘制，试试这个：

def rotate(*args):
    print 'rotate button press...'
    theta = 90
    rotated = ndimage.rotate(image, theta)
    im.set_data(rotated)
    canvas.draw()

更新以保持旋转

请注意，这是另存image为 的属性root。也许不是最好的方法，但它适用于示例。

root = Tk.Tk()
root.wm_title("minimal example")

root.image = plt.imread('test.jpg')
fig = plt.figure(figsize=(5,4))
im = plt.imshow(root.image) # later use a.set_data(new_data)
ax = plt.gca()
ax.set_xticklabels([]) 
ax.set_yticklabels([])

# a tk.DrawingArea
canvas = FigureCanvasTkAgg(fig, master=root)
canvas.show()
canvas.get_tk_widget().pack(side=Tk.TOP, fill=Tk.BOTH, expand=1)

def rotate(*args):
    print 'rotate button press...'
    root.image = ndimage.rotate(root.image, 90)
    im.set_data(root.image)
    canvas.draw()