# Tk_drag_canvas.py

# Tk_drag_canvas.py

from tkinter import *

root = Tk()
root.title("Tk_drag_canvas.py")

def scroll_start(event):
    canvas.scan_mark(event.x, event.y)

def scroll_move(event):
    canvas.scan_dragto(event.x, event.y, gain=1)

canvas = Canvas(width=400, height=400, background="grey")
xsb = Scrollbar(orient="horizontal", command=canvas.xview)
ysb = Scrollbar(orient="vertical", command=canvas.yview)
canvas.configure(yscrollcommand=ysb.set, xscrollcommand=xsb.set)
canvas.configure(scrollregion=(0,0,1000,1000))

xsb.grid(row=1, column=0, sticky="ew")
ysb.grid(row=0, column=1, sticky="ns")
canvas.grid(row=0, column=0, sticky="nsew")

colors = "red", "orange", "yellow", "green", "blue"
target = (0,0,1000,1000)
sz = 100
for n in colors:
    canvas.create_oval(target, outline=n, fill=n)
    target = target[0]+sz, target[1]+sz, target[2]-sz, target[3]-sz
canvas.create_text(50,10, anchor="nw",
                        text="CLICK AND DRAG TO MOVE THE CANVAS")

# This is what enables scrolling with the mouse...
canvas.bind("<ButtonPress-1>", scroll_start)
canvas.bind("<B1-Motion>", scroll_move)

root.mainloop()