Press 2 keys at once to move diagonally tkinter?

Question

How do I make something move on a canvas with 2 keys? Before anybody tells me that I did not do some research, I did. The reason I am still asking this is because I do not know what they are talking about. The people are talking about mini states and commands I do not know about.

from tkinter import *

def move(x,y):
    canvas.move(box,x,y)

def moveKeys(event):
    key=event.keysym
    if key =='Up':
        move(0,-10)
    elif key =='Down':
    move(0,10)
    elif key=='Left':
    move(-10,0)
    elif key=='Right':
        move(10,0)

window =Tk()
window.title('Test')

canvas=Canvas(window, height=500, width=500)
canvas.pack()

box=canvas.create_rectangle(50,50,60,60, fill='blue')
canvas.bind_all('<Key>',moveKeys)

Is there any way I can get 2 keys to move at once? I would like it to be done using this format, and not with mini states.

You can not do it using the format you specified. An event handler in tkinter will always respond to a single key press. If the constraint is that you can't use a "mini state", then you can't do it. — Bryan Oakley, May 19 '17 at 16:35

score 2 · Answer 1 · edited May 23 '17 at 12:18

If the "mini state" method you are talking about refers to this answer (Python bind - allow multiple keys to be pressed simultaneously), it is actually not that difficult to understand.

See below a modified & commented version of your code which follows that philosophy:

from tkinter import tk

window = tk.Tk()
window.title('Test')

canvas = tk.Canvas(window, height=500, width=500)
canvas.pack()

box = canvas.create_rectangle(50, 50, 60, 60, fill='blue')

def move(x, y):
    canvas.move(box, x, y)

# This dictionary stores the current pressed status of the (← ↑ → ↓) keys
# (pressed: True, released: False) and will be modified by Pressing or Releasing each key
pressedStatus = {"Up": False, "Down": False, "Left": False, "Right": False}

def pressed(event):
    # When the key "event.keysym" is pressed, set its pressed status to True
    pressedStatus[event.keysym] = True

def released(event):
    # When the key "event.keysym" is released, set its pressed status to False
    pressedStatus[event.keysym] = False

def set_bindings():
    # Bind the (← ↑ → ↓) keys's Press and Release events
    for char in ["Up", "Down", "Left", "Right"]:
        window.bind("<KeyPress-%s>" % char, pressed)
        window.bind("<KeyRelease-%s>" % char, released)

def animate():
    # For each of the (← ↑ → ↓) keys currently being pressed (if pressedStatus[key] = True)
    # move in the corresponding direction
    if pressedStatus["Up"] == True: move(0, -10)
    if pressedStatus["Down"] == True: move(0, 10)
    if pressedStatus["Left"] == True: move(-10, 0)
    if pressedStatus["Right"] == True: move(10, 0)
    canvas.update()
    # This method calls itself again and again after a delay (80 ms in this case)
    window.after(80, animate)

# Bind the (← ↑ → ↓) keys's Press and Release events
set_bindings()

# Start the animation loop
animate()

# Launch the window
window.mainloop()

Do you expect a 13 year old's brain to be able to process that. — 21harrisont, May 30 '17 at 02:11
Well, you could start by running the code to see if it does what you want. Then experiment with it changing one line at a time until you are happy with the result :) — Josselin, Jun 01 '17 at 09:00

Press 2 keys at once to move diagonally tkinter?

1 Answers1

Linked