Python Tkinter中的forget_pack()和forget_grid()用法

如果我们想要从屏幕或顶层取消任何小部件的映射，那么将使用forget()方法。有两种类型的忘记方法forget_pack()(类似于forget())和forget_grid()，它们分别用于pack()和grid()方法。

forget_pack()方法 –

Syntax: widget.forget_pack()

widget can be any valid widget which is visible.

代码1：

# Imports tkinter and ttk module
from tkinter import * 
from tkinter.ttk import *
  
# toplevel window
root = Tk()
  
# method to make widget invisible
# or remove from toplevel
def forget(widget):
  
     # This will remove the widget from toplevel
     # basically widget do not get deleted
     # it just becomes invisible and loses its position
     # and can be retrieve
     widget.forget()
  
# method to make widget visible
def retrieve(widget):
     widget.pack(fill = BOTH, expand = True )
  
# Button widgets
b1 = Button(root, text = "Btn 1" )
b1.pack(fill = BOTH, expand = True )
  
# See, in command forget() method is passed
b2 = Button(root, text = "Btn 2" , command = lambda : forget(b1))
b2.pack(fill = BOTH, expand = True )
  
# In command retrieve() method is passed
b3 = Button(root, text = "Btn 3" , command = lambda : retrieve(b1))
b3.pack(fill = BOTH, expand = True )
  
# infinite loop, interrupted by keyboard or mouse
mainloop()

输出如下：

忘记之后

检索后

注意忘记之前和之后以及检索之后, 按钮1位置的差异。

forget_grid()方法 –

Syntax: widget.forget_grid()

widget can be any valid widget which is visible.

注意 ：此方法只能用于grid() 几何方法。

代码2：

# Imports tkinter and ttk module
from tkinter import *
from tkinter.ttk import *
  
# toplevel window
root = Tk()
  
# method to make widget invisible
# or remove from toplevel
def forget(widget):
  
     # This will remove the widget from toplevel
     # basically widget do not get deleted
     # it just becomes invisible and loses its position
     # and can be retrieve
     widget.grid_forget()
  
# method to make widget visible
def retrieve(widget):
     widget.grid(row = 0 , column = 0 , ipady = 10 , pady = 10 , padx = 5 )
  
# Button widgets
b1 = Button(root, text = "Btn 1" )
b1.grid(row = 0 , column = 0 , ipady = 10 , pady = 10 , padx = 5 )
  
# See, in command forget() method is passed
b2 = Button(root, text = "Btn 2" , command = lambda : forget(b1))
b2.grid(row = 0 , column = 1 , ipady = 10 , pady = 10 , padx = 5 )
  
# In command retrieve() method is passed
b3 = Button(root, text = "Btn 3" , command = lambda : retrieve(b1))
b3.grid(row = 0 , column = 2 , ipady = 10 , pady = 10 , padx = 5 )
  
# infinite loop, interrupted by keyboard or mouse
mainloop()

输出如下：

忘记之后

检索后

注意按钮1的位置在之后保持不变忘记和恢复。用grid_forget()方法, 检索后可以将其放置在任何网格上, 但是通常会选择原始网格。

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