cpython/Demo/tkinter/matt/canvas-moving-w-mouse.py

56 lines
1.9 KiB
Python

from Tkinter import *
# this file demonstrates the movement of a single canvas item under mouse control
class Test(Frame):
###################################################################
###### Event callbacks for THE CANVAS (not the stuff drawn on it)
###################################################################
def mouseDown(self, event):
# remember where the mouse went down
self.lastx = event.x
self.lasty = event.y
def mouseMove(self, event):
# whatever the mouse is over gets tagged as CURRENT for free by tk.
self.draw.move(CURRENT, event.x - self.lastx, event.y - self.lasty)
self.lastx = event.x
self.lasty = event.y
###################################################################
###### Event callbacks for canvas ITEMS (stuff drawn on the canvas)
###################################################################
def mouseEnter(self, event):
# the CURRENT tag is applied to the object the cursor is over.
# this happens automatically.
self.draw.itemconfig(CURRENT, fill="red")
def mouseLeave(self, event):
# the CURRENT tag is applied to the object the cursor is over.
# this happens automatically.
self.draw.itemconfig(CURRENT, fill="blue")
def createWidgets(self):
self.QUIT = Button(self, text='QUIT', foreground='red',
command=self.quit)
self.QUIT.pack(side=LEFT, fill=BOTH)
self.draw = Canvas(self, width="5i", height="5i")
self.draw.pack(side=LEFT)
fred = self.draw.create_oval(0, 0, 20, 20,
fill="green", tags="selected")
self.draw.tag_bind(fred, "<Any-Enter>", self.mouseEnter)
self.draw.tag_bind(fred, "<Any-Leave>", self.mouseLeave)
Widget.bind(self.draw, "<1>", self.mouseDown)
Widget.bind(self.draw, "<B1-Motion>", self.mouseMove)
def __init__(self, master=None):
Frame.__init__(self, master)
Pack.config(self)
self.createWidgets()
test = Test()
test.mainloop()