On 5/21/2016 12:54 PM, Peter Otten wrote:
sweating_...@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).
The usual procedure is to create an App class and make images attributes
of the App instance. Then load_img would be a method and the first line
would be 'self.img = ...'. One can also have a list of images, to use
in a slide show, or a dict of images, so users can select.
--
Terry Jan Reedy
--
https://mail.python.org/mailman/listinfo/python-list
