Re: Image loading problem

From	Peter Otten <__peter__@web.de>
Newsgroups	comp.lang.python
Subject	Re: Image loading problem
Date	2016-05-21 18:54 +0200
Organization	None
Message-ID	<mailman.85.1463849696.27390.python-list@python.org> (permalink)
References	<743e5fbe-3a6c-49ea-ac5e-9bc055f652b5@googlegroups.com> <nhq3sl$hv8$1@ger.gmane.org>

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sweating_ant@yahoo.com wrote:

> I am working on an image project, and I can display my image in main(). I 
mean, I can load my image in my main(). Needless, it is awkward. I am trying 
to load my image with a function, but got an empty image window popped up, 
no image content loaded. Please take a look at code:
> 
> 
> 
> rom Tkinter import *
> 
> def load_img(win):      
>         img = PhotoImage(file="xxx.gif")
>         Label(win, image=img).pack()
>         
> win = Tk()
> load_img(win)
> win.mainloop()
> 
> Somebody can help me out? Thanks!

It's not your fault, there's an odd quirk in the library: you have to keep a 
reference of the PhotoImage instance around to prevent the image from being 
garbage-collected. For example

from Tkinter import *

def load_img(win):
    global img

    img = PhotoImage(file="xxx.gif")
    Label(win, image=img).pack()

win = Tk()
load_img(win)
win.mainloop()

will work because img is now a global that is not deleted until the script 
ends (but don't run the function twice -- then the first image will 
disappear).

Thread

Image loading problem "sweating_ant@yahoo.com" <huey.y.jiang@gmail.com> - 2016-05-21 08:22 -0700
  Re: Image loading problem Peter Otten <__peter__@web.de> - 2016-05-21 18:54 +0200
  Re: Image loading problem Peter Pearson <pkpearson@nowhere.invalid> - 2016-05-21 17:10 +0000
  Re: Image loading problem Gary Herron <gherron@digipen.edu> - 2016-05-21 10:16 -0700
  Re: Image loading problem Terry Reedy <tjreedy@udel.edu> - 2016-05-21 15:23 -0400
  Re: Image loading problem Random832 <random832@fastmail.com> - 2016-05-21 15:55 -0400
  Re: Image loading problem huey.y.jiang@gmail.com - 2016-05-21 21:01 -0700
  Re: Image loading problem Peter Otten <__peter__@web.de> - 2016-05-22 11:03 +0200
  Re: Image loading problem Michael Torrie <torriem@gmail.com> - 2016-05-22 13:37 -0600
  Re: Image loading problem Random832 <random832@fastmail.com> - 2016-05-22 16:19 -0400
    Re: Image loading problem Christian Gollwitzer <auriocus@gmx.de> - 2016-05-22 22:57 +0200

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