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I'm trying to make a entry value increase or decrease whenever the up or down arrow key is pressed. To do this i need to first find which entry that's in focus, and i'm trying to do that ".focus_get()". The problem is that i can't figure out how it works or what its returning. It is returning 1 unique number for each entry, something like: ".45191744" but this number changes each time i run the program. The following numbers is for the last 5 attempts, when running the code. ".50518728" ".53009096" ".55889592" ".51891896"

How can i get the variable name of the focused entry?

Here is my code:

def get_focus1(event): print("return: event.widget is", event.widget) print("focus is:", window2.focus_get()) print(window2.focus_get()) print(help(window2.Entry)) window2 = Tk() eyear1 = Entry(window2, width=4, font=("Helvetica", 16)) # Entry for year eyear1.insert(10, defaultYear) eyear1.grid(row=1, column=1) emonth1 = Entry(window2, width=4, font=("Helvetica", 16)) # Entry for Month emonth1.insert(10, defaultMonth) emonth1.grid(row=1, column=2) eday1 = Entry(window2, width=4, font=("Helvetica", 16)) # Entry for day eday1.insert(10, defaultDay) eday1.grid(row=1, column=3) window2.bind('<Left>', get_focus1) mainloop()
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  • Can you post some code? You're printing the object that's returned from focus_get? If so, the numbers you're seeing are probably the object that's in focus's representation. Commented Jan 9, 2015 at 19:34
  • Just updated my question Commented Jan 9, 2015 at 19:43

2 Answers 2

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focus_get returns the actual object. What you want to do, assuming your not using textvariable for a good reason (see Bryan's comment), is to clear the text and re-write the new value (do some validation obviously). What you end up is something like this:

from tkinter import * def up(event): # warning, exceptions can happen old = int(event.widget.get()) # this gives back the actual object! event.widget.delete(0, END) # delete existing text event.widget.insert(10, old + 1) # put new text in def down(event): # warning, exceptions can happen old = int(event.widget.get()) # this gives back the actual object! event.widget.delete(0, END) # delete existing text event.widget.insert(10, old - 1) # put new text in window2 = Tk() eyear1 = Entry(window2, width=4, font=("Helvetica", 16)) # Entry for year eyear1.insert(10, 2015) eyear1.grid(row=1, column=1) emonth1 = Entry(window2, width=4, font=("Helvetica", 16)) # Entry for Month emonth1.insert(10, 1) emonth1.grid(row=1, column=2) eday1 = Entry(window2, width=4, font=("Helvetica", 16)) # Entry for day eday1.insert(10, 10) eday1.grid(row=1, column=3) # bind both keys to corresponding event handlers window2.bind('<Up>', up) window2.bind('<Down>', down) mainloop()
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3 Comments

The good reason for not using textvariable is that textvariable is completely unnecessary in most circumstances. It adds a tiny bit of complexity for no real gain in most circumstances (where "complexity" is defined as "creating more objects than you really need").
@BryanOakley I'm not experienced with Tkinter, so I'll take your word for it :) That's what I saw people use, so I'll remove it.
@RasmusGP make sure you do some checking, since it can easily break. This was just to make a point. Good luck.
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Remember that when you call print, you are getting the representation of an object, not necessarily the object itself. To show you what's going on, add this to your get_focus1 function:

print("focus object class:", window2.focus_get().__class__)

You should see that it is indeed returning a reference to an Entry widget, meaning you can call all the normal methods on that object.

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7 Comments

I see, this might be a stupid question, but how to i get the entry name of that entry? i need to change the text in it
@RasmusGP: you don't need the entry name, event.widget is the widget: widget=event.widget; value=widget.get()
But my problem now is that i have to be able to set a limit to that entry like, the "emonth1" entry shouldn't be able to get higher then 12. So i need a way to check whether its a year, month, day, hour or minute entry. I could hardcode it but i have 2 of each entry, so i would love to be able to get the variable name.
@RasmusGP: You can add a custom attribute to each widget, for example emonth1.limit=12. Then you can later fetch that limit in the hander with event.widget.limit.
How does that work? when i try this: emonth1 = Entry(window2, width=4, font=("Helvetica", 16), limit = 12) it says unknown option. And when i do emonth1.limit=12it nothing happens. does it prevent the value to get higher then 12?
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