Tkinter

Tkinter is a Python API for the Tk GUI. It is built into the Python standard library and is cross platform.

Layout

`tk.Frame`

You can use tk.Frame as general containers.

Images

To display an image, create a tk.Canvas and then use canvsa.create_image.

Example

import tkinter as tk
from PIL import Image, ImageTk
import requests

image_url = 'https://via.placeholder.com/256/0000FF/'
image = Image.open(requests.get(image_url, stream=True).raw)
window = tk.Tk()
main_frame = tk.Frame(window)
main_frame.pack()
canvas = tk.Canvas(main_frame,
                   width=image.size[0],
                   height=image.size[1])
canvas.pack()
photo_img = ImageTk.PhotoImage(image=image)
canvas_image = canvas.create_image(0, 0, image=photo_img, anchor=tk.NW)
window.mainloop()

# To update the image later on..
image_url2 = 'https://via.placeholder.com/256/FF00FF/'
image2 = Image.open(requests.get(image_url, stream=True).raw)
photo_img = ImageTk.PhotoImage(image=image2)
canvas.itemconfigure(canvas_image, image=photo_img)

Notes

Make sure the ImageTk.PhotoImage does not get garbage collected.

Animation Loop

For interactive applications, you may want an animation loop called every few milliseconds.
To accomplish this, use .after.

Example

import tkinter as tk
import time

last_time = time.time()


def animation_loop():
    global last_time
    now = time.time()
    delta_time = now - last_time
    print("Time elapsed", delta_time)
    last_time = now
    window.after(1, animation_loop)


window = tk.Tk()
animation_loop()
window.mainloop()

Keypress

To just detect key presses:

Example

import tkinter as tk


def key_pressed(event):
    print("Key pressed", event.char, event.keysym)


window = tk.Tk()
window.bind("<Key>", key_pressed)
window.mainloop()

Notes

Use <KeyRelease> to detect key releases.