from tkinter import *
# this file demonstrates the creation of widgets as part of a canvas object
class Test(Frame):
###################################################################
###### Event callbacks for THE CANVAS (not the stuff drawn on it)
###################################################################
def mouseDown(self, event):
# see if we're inside a dot. If we are, it
# gets tagged as CURRENT for free by tk.
if not event.widget.find_withtag(CURRENT):
# there is no dot here, so we can make one,
# and bind some interesting behavior to it.
# ------
# create a dot, and mark it as current
fred = self.draw.create_oval(
event.x - 10, event.y -10, event.x +10, event.y + 10,
fill="green")
self.draw.tag_bind(fred, "<Enter>", self.mouseEnter)
self.draw.tag_bind(fred, "<Leave>", self.mouseLeave)
self.lastx = event.x
self.lasty = event.y
def mouseMove(self, event):
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")
print(self.draw.coords(CURRENT))
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)
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()
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