Each window component contains a dictionary of its attributes. After a component has been added to the application window, the programmer can access and modify its attributes by using the subscript with the name of the attribute (a string), as follows:
widget[attribute name]
widget[attribute name] = value
For example, a label has a text font and a foreground color that can be modified in this manner. A label also can show either text or an image, depending on the setting of these attributes. The next program, which displays an image and a caption, shows how to set the image, font, and color attributes of labels.
"""File: imagedemo.py."""
from breezypythongui import EasyFrame
from tkinter import PhotoImage, N, S, W, E
from tkinter.font import Font
class ImageDemo(EasyFrame):
"""Displays an image and a caption."""
def __init__(self):
"""Sets up the window and widgets."""
EasyFrame.__init__(self, title = "Image Demo")
imageLabel = self.addLabel(text = "",
row = 0, column = 0,
sticky = N+S+W+E)
textLabel = self.addLabel(text = "Smokey the cat",
row = 1, column = 0,
sticky = N+S+W+E)
# Load the image and associate it with the image label.
self.image = PhotoImage(file = "smokey.gif")
imageLabel["image"] = self.image
# Set the font and color of the caption.
font = Font(family = "Verdana", size = 20, slant = "italic")
textLabel["font"] = font
textLabel["foreground"] = "blue"
#Instantiate and pop up the window.
ImageDemo().mainloop()
Note that this program must import the PhotoImage and Font classes and the constants N, S, W, and E from the relevant tkinter modules. These constants are used to center the two labels in their respective grid cells, overriding the default placement of a label to the northwest. Here is the window produced by the program:
