Tkinter Label does not show Image

Question

I'm trying to learn some tkinter. I can't get tkinter to display an icon. I don't know where it goes wrong. It does not produce any error and it respects the size of the image, but it's invisible. Everything I found online tells to add a second reference to prevent garbage collection from python, but somehow this did not the trick. Here is the part of my code that goes wrong:

from Tkinter import *
from PIL import Image, ImageTk

class GUI:

    def __init__(self, master):

        frame = Frame(master)
        frame.pack()

        #status bar
        self.bar = Frame(root, relief=RIDGE, borderwidth=5)
        self.bar.pack(side=TOP)

        self.iconPath = 'data/icons/size.png'
        self.icon = ImageTk.PhotoImage(Image.open(self.iconPath))
        self.icon_size = Label(self.bar, image = self.icon)
        self.icon_size.pack(side=LEFT)

root = Tk()


app = GUI(root)

root.mainloop()

Answer 1

When you add a PhotoImage or other Image object to a Tkinter widget, you must keep your own reference to the image object. If you don’t, the image won’t always show up.

Decision here

Answer 2

For some reason (I don't understand exactly why) you must anchor the image object into the widget in order for it to display. Therefore try the following change at your code:

from Tkinter import *
from PIL import Image, ImageTk

class GUI:

    def __init__(self, master):

        frame = Frame(master)
        frame.pack()

        #status bar
        self.bar = Frame(root, relief=RIDGE, borderwidth=5)
        self.bar.pack(side=TOP)

        self.iconPath = 'data/icons/size.png'
        self.icon = ImageTk.PhotoImage(Image.open(self.iconPath))
        self.icon_size = Label(self.bar)
        self.icon_size.image = self.icon  # <== this is were we anchor the img object
        self.icon_size.configure(image=self.icon)
        self.icon_size.pack(side=LEFT)

root = Tk()


app = GUI(root)

root.mainloop()

Good Luck!