python - Why does this after statement not work? -

this question has answer here:

• tkinter: how use after method 1 answer

i have after statement in move_r function. when hit space bar says

typeerror: move_r() missing 1 required positional argument: 'event' 

i relatively know means can't figure out change program supposed draw rocket, , when click space rocket moves up. unfortunately program goes 100 everytime click space instead of going once hit space goal. code is:

from tkinter import * import random, time tk = tk() tk.wm_attributes('-topmost', 1) canvas = canvas(tk, width=1000, height=1000, bd=0) canvas.pack() def rocket(): #draws rocket         rocketbase=canvas.create_rectangle(x2+50, y2-50, x3-50, y3-90, fill ='blue')         rrocketfin=canvas.create_rectangle(x2+60, y2-50, x3-40, y3-20, fill ='#e69100')         lrocketfin=canvas.create_rectangle(x2+40, y2-50, x3-60, y3-20, fill ='#e69100')         mrocketfin=canvas.create_rectangle(x2+54, y2-50, x3-53, y3-20, fill ='#e69100')         lrockethead=canvas.create_rectangle(x2+45, y2-125, x3-60, y3-70, fill ='#e69100')         rrockethead=canvas.create_rectangle(x2+60, y2-125, x3-45, y3-70, fill ='#e69100') def move_r(event):     if event.keysym == 'space':         global y2         global y3         y2-=100         y3-=100         canvas.after(100, move_r )  x2=460 y2=940 x3=570 y3=900 r1=none  tk.bind('<keypress-space>', move_r) while true:     background = canvas.create_rectangle(0, 0, 1000, 1000, fill = 'red')      base=canvas.create_rectangle(0, 1000, 1000, 900, fill='#86592d')     rocket()     tk.update()   tk.mainloop() 

here rocket moves; doesn't fix problems, addresses question asked:

the event key_press - generated when press space bar, , sent event handler.

the event handler receives event, , acts on (identifies event, , directs flow should - here, move rocket).

move rocket that, moves rocket callback loop.

from tkinter import * import random, time tk = tk() tk.wm_attributes('-topmost', 1) canvas = canvas(tk, width=1000, height=1000, bd=0) canvas.pack()   def rocket(): #draws rocket         rocketbase=canvas.create_rectangle(x2+50, y2-50, x3-50, y3-90, fill ='blue')         rrocketfin=canvas.create_rectangle(x2+60, y2-50, x3-40, y3-20, fill ='#e69100')         lrocketfin=canvas.create_rectangle(x2+40, y2-50, x3-60, y3-20, fill ='#e69100')         mrocketfin=canvas.create_rectangle(x2+54, y2-50, x3-53, y3-20, fill ='#e69100')         lrockethead=canvas.create_rectangle(x2+45, y2-125, x3-60, y3-70, fill ='#e69100')         rrockethead=canvas.create_rectangle(x2+60, y2-125, x3-45, y3-70, fill ='#e69100')  def handle_key_press(e):     if e.keysym == 'space':         move_r()  def move_r():     global y2     global y3     y2 -= 50     y3 -= 50     rocket()     tk.update()     canvas.after(100, move_r)    x2=460 y2=940 x3=570 y3=900 r1=none  tk.bind('<keypress-space>', handle_key_press)  background = canvas.create_rectangle(0, 0, 1000, 1000, fill = 'red')  base = canvas.create_rectangle(0, 1000, 1000, 900, fill='#86592d') rocket() tk.update()   tk.mainloop()