[Tutor] Tkinter Entry field text

[brandon w]

On 09/10/2011 10:16 AM, Wayne Werner wrote:
> On Thu, Sep 8, 2011 at 9:31 PM, brandon w <thisisonlyatest at gmx.com 
> <mailto:thisisonlyatest at gmx.com>> wrote:
>
>     How do you display text in a Entry field and have it disappear
>     when a person clicks in it?
>     <snip some code> To get text into this box the person must first
>     delete what is already in there.
>
>     Python 2.6.6
>
>
>  Think about the process. You're already mostly there: you're 
> displaying data already, and you know what you want to do.
>
> You'll want to take a look at binding events, and if you Google for 
> "tkinter events" (http://www.google.com/search?q=tkinter+events) then 
> your first result takes you here: 
> http://effbot.org/tkinterbook/tkinter-events-and-bindings.htm
>
> To point you in the right direction, you want to take a look at the 
> <FocusIn> event. If you're not familiar with what a callback is, you 
> should also read this page: http://effbot.org/zone/tkinter-callbacks.htm
>
> If you still have problems after that, show us what else you've tried 
> and we'll be happy to give you more pointers in the right direction.
>
>
>
> Of course, while this answers your questions, I would be remiss if I 
> didn't suggest a few more things about your program in general.
>
> > label1 = Label(root, text="Enter you password: ")
>
> label1 isn't a terribly descriptive name. That's fine if you don't 
> intend to actually do anything with the label. However, you can make 
> this even more explicit by chaining the commands together. Since 
> Label() returns a label, you can add a dot to the end and treat it 
> just like you would the variable:
>
> Label(root, text="Enter you password: ").grid(sticky=W, row=0, column=0)
>
> That will create your label and stick it in the grid in one step, and 
> makes it clear to anyone reading your code (including yourself down 
> the road!) that you don't care to do anything with that label.
>
> Next:
>
> > enter_data1 = Entry(root, bg = "pale green")
>
> enter_data1 also suffers from the same naming problem. It doesn't 
> describe what the variable is or does very well, aside from entering 
> data. You could change it to something like "password_entry" - which 
> tells anyone reading your program that the variable should contain 
> something that lets you do some password entry. Just naming it 
> password would also be better than enter_data1.
>
> One other issue that you should consider - with the options you have 
> set, anyone could see what you typed in as your password. If you're 
> just using this as a testing program to play around with, that's 
> probably OK, but what's even better is to change what's shown in the 
> box. You can do this by setting the "show" option, either in the 
> constructor or somewhere later:
>
> from Tkinter import *
>
> root = Tk()
> entry = Entry(root)
> entry.pack()
> entry.insert(0, "My Cool Password")
> entry.config(show="*")
> root.mainloop()
>
> The nice thing about the config() method is that it allows you to 
> change config attributes later. You can combine this knowledge with 
> some of what I mentioned earlier to show 'password' until they 
> navigate to the field, and then just show asterisks.
>
> For bonus points, if they leave the password field without typing a 
> password, can you make it show 'password' again?
>
> HTH,
> Wayne
Wayne,

Your advice was extremely helpful. I pointed me into the right 
direction. I got the code to work after some time. I know how to make it 
show  the "password" again. I would have to do this:

from Tkinter import *

root = Tk()
root.title("Show me your Password")
root.geometry("375x100+600+250")
root.grid()

def callback(event):
     passwd_entry.delete(0, END) # It would come back because there is 
no .insert() function.
     return

[....snip...]

#=========================

Here is the final working code:

#!/usr/bin/python

from Tkinter import *

root = Tk()
root.title("Show me your Password")
root.geometry("375x100+600+250")
root.grid()

def callback(event):
     field0 = varText1.get()
     passwd_entry.delete(0, END)
     passwd_entry.insert(0, field0)
     return

def showPasswd():
     field1 = varText.get()
     passwd_display.delete(0, END)
     passwd_display.insert(0, field1)
     return

Label(root, text="Type your password in this box: ").grid(sticky=W, 
row=0, column=0)

Label(root, text="Your password is:").grid(sticky=W, row=2, column=0)

varText = StringVar()
varText.set("Enter password")
passwd_entry = Entry(root, textvariable=varText, bg = "pale green")
passwd_entry.bind("<Enter>", callback)
passwd_entry.config(show="*")
passwd_entry.grid(row=0, column=1)

varText1 = StringVar(None)
passwd_display = Entry(root, textvariable=varText1, bg = "pale green")
passwd_display.grid(row=2, column=1)

Button(root, text="Show Password", width=10, 
command=showPasswd).grid(sticky=W, row=1, column=0)


root.mainloop()


Thanks a lot for your help!!!!!


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