Move object in python tkinter canvas

问题

so I have a submarine:

from tkinter import *
HEIGHT = 500
WIDTH = 800
window = Tk()
window.title("Bubble Blaster")
c = Canvas(window, width=WIDTH, height=HEIGHT, bg="darkblue")
c.pack()
ship_id = c.create_polygon(5, 5, 5, 25, 30, 15, fill="red")
ship_id2 = c.create_oval(0, 0, 30, 30, outline="red")

and Im reading a book on how to make the sub move, this is what it says:

def move_ship(event):
    if event.keysym == "up":
        c.move(ship_id, 0, -ship_spd)
        c.move(ship_id2, 0, -ship_spd)
    elif event.keysym == "Down":
        c.move(ship_id, 0, ship_spd)
        c.move(ship_id2, 0, ship_spd)
    elif event.keysym == "Left":
        c.move(ship_id, -ship_spd, 0)
        c.move(ship_id2,  -ship_spd, 0)
    elif event.keysym == "Right":
        c.move(ship_id, ship_spd, 0)
        c.move(ship_id2,  ship_spd, 0)
    c.bind_all('<key', move_ship)

When I run it, it gives me an error:
PS. Im doing it in a snippet because Ctrl+v wont do all of the message

<h4 style="color: red">Traceback (most recent call last):
  File "C:\Users\Bloxy Craft\Desktop\Bubble Blaster.py", line 28, in &lt;module&gt;
    c.bind_all('&lt;key&gt;', move_ship)
  File "C:\Users\Bloxy Craft\AppData\Local\Programs\Python\Python36\lib\tkinter\__init__.py", line 1257, in bind_all
    return self._bind(('bind', 'all'), sequence, func, add, 0)
  File "C:\Users\Bloxy Craft\AppData\Local\Programs\Python\Python36\lib\tkinter\__init__.py", line 1200, in _bind
    self.tk.call(what + (sequence, cmd))
_tkinter.TclError: bad event type or keysym "key"</h4>

Can someone help me?
Thanks!
- Bloxy Craft

回答1:

Like Bryan Oakley said you need to replace '<key' with '<Key>'. Also you need to replace if event.keysym == "up": with if event.keysym == "Up": in your code (U in 'Up' must be capital). Hole code is:

from tkinter import *
HEIGHT = 500
WIDTH = 800
window = Tk()
window.title("Bubble Blaster")
c = Canvas(window, width=WIDTH, height=HEIGHT, bg="darkblue")
c.pack()
ship_id = c.create_polygon(5, 5, 5, 25, 30, 15, fill="red")
ship_id2 = c.create_oval(0, 0, 30, 30, outline="red")

def move_ship(event):
    if event.keysym == "Up":
        c.move(ship_id, 0, -ship_spd)
        c.move(ship_id2, 0, -ship_spd)
    elif event.keysym == "Down":
        c.move(ship_id, 0, ship_spd)
        c.move(ship_id2, 0, ship_spd)
    elif event.keysym == "Left":
        c.move(ship_id, -ship_spd, 0)
        c.move(ship_id2,  -ship_spd, 0)
    elif event.keysym == "Right":
        c.move(ship_id, ship_spd, 0)
        c.move(ship_id2,  ship_spd, 0)

c.bind_all('<Key>', move_ship)

来源：https://stackoverflow.com/questions/45872276/move-object-in-python-tkinter-canvas

标签

python

user-interface

tkinter

tkinter-canvas