python tkinter 条目变量未定义

Question

Can anyone help me with this error I don't know how to fix this it.

from tkinter import *

def get_data():
    target=Entry.get(note)

def show():
    note=Entry(root)
    note.grid(row=2,column=1)
    b2=Button(root,text='view',command=get_data).grid(row=2,column=2)

root=Tk()
root.title("test")
Label(root,text="click").grid(row=1,column=1)
b1=Button(root,text='click',command=show).grid(row=1,column=2)
root.mainloop()

Error:

target=Entry.get(note)
NameError: name 'note' is not defined

Answer 1

The easy fix is to define note globally, then just lay it out in the function:

from tkinter import *
def get_data():
    target=Entry.get(note)
def show():
    note.grid(row=2,column=1)
    b2=Button(root,text='view',command=get_data).grid(row=2,column=2)
root=Tk()
root.title("test")
note=Entry(root)
Label(root,text="click").grid(row=1,column=1)
b1=Button(root,text='click',command=show).grid(row=1,column=2)
root.mainloop()

Answer 2

You can pass parameters to functions triggered by buttons:

from tkinter import *

def get_data(note):
    target = Entry.get(note)

def show(root):
    note = Entry(root)
    note.grid(row=2, column=1)
    b2 = Button(root, text='view', command=lambda: get_data(note)).grid(row=2, column=2)

def main():
    root = Tk()
    root.title("test")
    Label(root,text="click").grid(row=1, column=1)
    b1 = Button(root, text='click', command=lambda: show(root)).grid(row=1, column=2)
    root.mainloop()

if __name__ == '__main__':
    main()

I've used a lambda to make the call with the parameter note .