python - List available font families in `tkinter`

Question

In many tkinter examples available out there, you may see things like:

canvas.create_text(x, y, font=('Helvetica', 12), text='foo')

However, this may not work when run in your computer (the result would completely ignore the font parameter). Aparently, the font parameter is ignored if there is any incorrect value in it.

In order to check if the font family is valid, how can I list all available in my system?

Answer 1

This question has been answered fully, but it's useful for me to be able to see what every font looks like so that I'm sure of which one I would like to use. In the interest of saving someone else from reinventing the wheel, I'll post my code here. As above, each font family is shown in a scrolling window. The difference is that each font in this code is printed in the font itself.

from tkinter import *
from tkinter import font

root = Tk()
root.title('Font Families')
fonts=list(font.families())
fonts.sort()

def populate(frame):
    '''Put in the fonts'''
    listnumber = 1
    for item in fonts:
        label = "listlabel" + str(listnumber)
        label = Label(frame,text=item,font=(item, 16)).pack()
        listnumber += 1

def onFrameConfigure(canvas):
    '''Reset the scroll region to encompass the inner frame'''
    canvas.configure(scrollregion=canvas.bbox("all"))

canvas = Canvas(root, borderwidth=0, background="#ffffff")
frame = Frame(canvas, background="#ffffff")
vsb = Scrollbar(root, orient="vertical", command=canvas.yview)
canvas.configure(yscrollcommand=vsb.set)

vsb.pack(side="right", fill="y")
canvas.pack(side="left", fill="both", expand=True)
canvas.create_window((4,4), window=frame, anchor="nw")

frame.bind("<Configure>", lambda event, canvas=canvas: onFrameConfigure(canvas))

populate(frame)

root.mainloop()

I hope this helps somebody.