python新建画布_如何在tkinter画布上创建按钮？

我创建了一个框架，然后创建了一个画布。

我接下来要做的是在画布上添加一个按钮。

然而，当我打包按钮我看不到画布！

我试过的是：from Tkinter import Tk, Canvas, Frame, Button

from Tkinter import BOTH, W, NW, SUNKEN, TOP, X, FLAT, LEFT

class Example(Frame):

def __init__(self, parent):

Frame.__init__(self, parent)

self.parent = parent

self.initUI()

def initUI(self):

self.parent.title("Layout Test")

self.config(bg = '#F0F0F0')

self.pack(fill = BOTH, expand = 1)

#create canvas

canvas1 = Canvas(self, relief = FLAT, background = "#D2D2D2",

width = 180, height = 500)

canvas1.pack(side = TOP, anchor = NW, padx = 10, pady = 10)

#add quit button

button1 = Button(canvas1, text = "Quit", command = self.quit,

anchor = W)

button1.configure(width = 10, activebackground = "#33B5E5",

relief = FLAT)

button1.pack(side = TOP)

def main():

root = Tk()

root.geometry('800x600+10+50')

app = Example(root)

app.mainloop()

if __name__ == '__main__':

main()