Python 如何将占位符添加到 tkinter 中的条目？
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/27820178/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
How to add placeholder to an Entry in tkinter?
提问by Pierce
I have created a login window in tkinter which has two Entry field, first one is Username and second one is Password.
code
我在 tkinter 中创建了一个登录窗口，它有两个输入字段，第一个是用户名，第二个是密码。
代码
from tkinter import *
ui = Tk()
e1 = Entry(ui)
#i need a placeholder "Username" in the above entry field
e1.pack()
ui.mainloop()
I want a placeholder called "Username" in the Entry, but if you click inside, the text should dissapear.
我想要一个名为“用户名”的占位符Entry，但如果你点击里面，文本应该消失。
采纳答案by Stephen Lin
You need to set a default value for this entry. Like this:
您需要为此条目设置默认值。像这样：
from tkinter import *
ui = Tk()
e1 = Entry(ui)
e1.insert(0, 'username')
e1.pack()
ui.mainloop()
Then if you want to delete the content when you click the entry, then you have to bind a mouse click event with an event handler method to update content of this entry. Here is a linkfor you.
那么如果你想在点击条目时删除内容，那么你必须绑定一个鼠标点击事件和一个事件处理程序方法来更新这个条目的内容。这是给你的链接。
回答by Nae
You can create a class that inherits from Entrylike below:
您可以创建一个继承自Entry如下所示的类：
import tkinter as tk
class EntryWithPlaceholder(tk.Entry):
def __init__(self, master=None, placeholder="PLACEHOLDER", color='grey'):
super().__init__(master)
self.placeholder = placeholder
self.placeholder_color = color
self.default_fg_color = self['fg']
self.bind("<FocusIn>", self.foc_in)
self.bind("<FocusOut>", self.foc_out)
self.put_placeholder()
def put_placeholder(self):
self.insert(0, self.placeholder)
self['fg'] = self.placeholder_color
def foc_in(self, *args):
if self['fg'] == self.placeholder_color:
self.delete('0', 'end')
self['fg'] = self.default_fg_color
def foc_out(self, *args):
if not self.get():
self.put_placeholder()
if __name__ == "__main__":
root = tk.Tk()
username = EntryWithPlaceholder(root, "username")
password = EntryWithPlaceholder(root, "password", 'blue')
username.pack()
password.pack()
root.mainloop()
回答by Aman Khandelwal
from tkinter import *
root=Tk()
root.geometry("300x200+600+250")
root.config(background="#E0FFFF")
root.resizable(False,False)
def userText(event):
e1.delete(0,END)
usercheck=True
def passText(event):
e2.delete(0, END)
passcheck=True
a=StringVar()
b=StringVar()
usercheck=False
passcheck=False
Label(root,text="User name",bg="#E0FFFF").place(x=20,y=50)
e1= Entry(root,textvariable=a)
e1.place(x=100,y=50)
e1.insert(0,"Enter username")
e1.bind("<Button>",userText)
Label(root,text="Password",bg="#E0FFFF").place(x=20,y=95)
e2= Entry(root,textvariable=b)
e2.place(x=100,y=95)
e2.insert(0,"Enter password")
e2.bind("<Button>",passText)
root.mainloop()
回答by Daniyal Ahmad
This will work for any place holder you want.
这适用于您想要的任何占位符。
from tkinter import *
root = Tk()
my_entry = Entry(root, width=50)
my_entry.pack()
my_entry.insert(0, "Place Holder")
my_entry.configure(state=DISABLED)
def on_click(event):
my_entry.configure(state=NORMAL)
my_entry.delete(0, END)
# make the callback only work once
my_entry.unbind('<Button-1>', on_click_id)
on_click_id = my_entry.bind('<Button-1>', on_click)
root.mainloop()
